feat!(terminal): inline viewport

* feat(chart): allow custom alignment of first X-Axis label

* refactor(chart): rename ambiguous function parameter

* feat(chart): allow custom alignment of Y-Axis labels

* refactor(chart): refactor axis test cases

* refactor(chart): rename minor variable

* fix(chart): force centered x-axis label near Y-Axis

* fix(chart): fix subtract overflow on small rendering area

* refactor(chart): rename alignment property

* refactor(chart): merge two nested conditions

* refactor(chart): decompose x labels rendering loop

.github/workflows/ci.yml

@@ -9,7 +9,7 @@ on:
 name: CI
 
 env:
-  CI_CARGO_MAKE_VERSION: 0.32.9
+  CI_CARGO_MAKE_VERSION: 0.35.6
 
 jobs:
   linux:
@@ -17,7 +17,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        rust: ["1.44.0", "stable"]
+        rust: ["1.52.1", "stable"]
     steps:
       - name: "Install dependencies"
         run: sudo apt-get install libncurses5-dev
@@ -38,22 +38,16 @@ jobs:
       - name: "Install cargo-make"
         if: steps.cache-cargo-make.outputs.cache-hit != 'true'
         run: cargo install cargo-make --version ${{ env.CI_CARGO_MAKE_VERSION }}
-      - name: "Format"
-        run: cargo make fmt
-      - name: "Check"
-        run: cargo make check
-      - name: "Test"
-        run: cargo make test
+      - name: "Format / Build / Test"
+        run: cargo make ci
         env:
           RUST_BACKTRACE: full
-      - name: "Clippy"
-        run: cargo make clippy
   windows:
     name: Windows
     runs-on: windows-latest
     strategy:
       matrix:
-        rust: ["1.44.0", "stable"]
+        rust: ["1.52.1", "stable"]
     steps:
       - uses: actions/checkout@v1
       - uses: hecrj/setup-rust-action@967aec96c6a27a0ce15c1dac3aaba332d60565e2
@@ -73,13 +67,7 @@ jobs:
       - name: "Install cargo-make"
         if: steps.cache-cargo-make.outputs.cache-hit != 'true'
         run: cargo install cargo-make --version ${{ env.CI_CARGO_MAKE_VERSION }}
-      - name: "Format"
-        run: cargo make fmt
-      - name: "Check"
-        run: cargo make check
-      - name: "Test"
-        run: cargo make test
+      - name: "Format / Build / Test"
+        run: cargo make ci
         env:
           RUST_BACKTRACE: full
-      - name: "Clippy"
-        run: cargo make clippy

CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## To be released
 
+### Features
+
+* Add option to `widgets::List` to repeat the hightlight symbol for each line of multi-line items (#533).
+
 ## v0.16.0 - 2021-08-01
 
 ### Features

Cargo.toml

@@ -17,111 +17,79 @@ edition = "2018"
 [badges]
 
 [features]
-default = ["termion"]
-curses = ["easycurses", "pancurses"]
+default = ["crossterm"]
 
 [dependencies]
-bitflags = "1.0"
+tracing = "0.1"
+bitflags = "1.3"
 cassowary = "0.3"
 unicode-segmentation = "1.2"
 unicode-width = "0.1"
 termion = { version = "1.5", optional = true }
-rustbox = { version = "0.11", optional = true }
-crossterm = { version = "0.20", optional = true }
-easycurses = { version = "0.12.2", optional = true }
-pancurses = { version = "0.16.1", optional = true, features = ["win32a"] }
-serde = { version = "1", "optional" = true, features = ["derive"]}
+crossterm = { version = "0.22", optional = true }
+serde = { version = "1", optional = true, features = ["derive"]}
 
 [dev-dependencies]
+tracing-subscriber = "0.2"
 rand = "0.8"
 argh = "0.1"
 
-[[example]]
-name = "canvas"
-path = "examples/canvas.rs"
-required-features = ["termion"]
-
-[[example]]
-name = "user_input"
-path = "examples/user_input.rs"
-required-features = ["termion"]
-
-[[example]]
-name = "gauge"
-path = "examples/gauge.rs"
-required-features = ["termion"]
-
 [[example]]
 name = "barchart"
-path = "examples/barchart.rs"
-required-features = ["termion"]
-
-[[example]]
-name = "chart"
-path = "examples/chart.rs"
-required-features = ["termion"]
-
-[[example]]
-name = "paragraph"
-path = "examples/paragraph.rs"
-required-features = ["termion"]
-
-[[example]]
-name = "list"
-path = "examples/list.rs"
-required-features = ["termion"]
-
-[[example]]
-name = "table"
-path = "examples/table.rs"
-required-features = ["termion"]
-
-[[example]]
-name = "tabs"
-path = "examples/tabs.rs"
-required-features = ["termion"]
-
-[[example]]
-name = "custom_widget"
-path = "examples/custom_widget.rs"
-required-features = ["termion"]
-
-[[example]]
-name = "layout"
-path = "examples/layout.rs"
-required-features = ["termion"]
-
-[[example]]
-name = "popup"
-path = "examples/popup.rs"
-required-features = ["termion"]
-
-[[example]]
-name = "block"
-path = "examples/block.rs"
-required-features = ["termion"]
-
-[[example]]
-name = "sparkline"
-path = "examples/sparkline.rs"
-required-features = ["termion"]
-
-[[example]]
-name = "termion_demo"
-path = "examples/termion_demo.rs"
-required-features = ["termion"]
-
-[[example]]
-name = "rustbox_demo"
-path = "examples/rustbox_demo.rs"
-required-features = ["rustbox"]
-
-[[example]]
-name = "crossterm_demo"
-path = "examples/crossterm_demo.rs"
 required-features = ["crossterm"]
 
 [[example]]
-name = "curses_demo"
-path = "examples/curses_demo.rs"
-required-features = ["curses"]
+name = "block"
+required-features = ["crossterm"]
+
+[[example]]
+name = "canvas"
+required-features = ["crossterm"]
+
+[[example]]
+name = "chart"
+required-features = ["crossterm"]
+
+[[example]]
+name = "custom_widget"
+required-features = ["crossterm"]
+
+[[example]]
+name = "gauge"
+required-features = ["crossterm"]
+
+[[example]]
+name = "layout"
+required-features = ["crossterm"]
+
+[[example]]
+name = "list"
+required-features = ["crossterm"]
+
+[[example]]
+name = "paragraph"
+required-features = ["crossterm"]
+
+[[example]]
+name = "popup"
+required-features = ["crossterm"]
+
+[[example]]
+name = "sparkline"
+required-features = ["crossterm"]
+
+[[example]]
+name = "table"
+required-features = ["crossterm"]
+
+[[example]]
+name = "tabs"
+required-features = ["crossterm"]
+
+[[example]]
+name = "user_input"
+required-features = ["crossterm"]
+
+[[example]]
+name = "inline"
+required-features = ["crossterm"]

Makefile.toml

@@ -1,28 +1,34 @@
 [config]
 skip_core_tasks = true
 
-[env.TUI_FEATURES]
-source = "${CARGO_MAKE_RUST_TARGET_OS}"
-default_value = "unknown"
-
-[env.TUI_FEATURES.mapping]
-linux = "serde,crossterm,termion,rustbox,curses"
-macos = "serde,crossterm,termion,rustbox,curses"
-windows = "serde,crossterm"
-
-[tasks.default]
-dependencies = [
-  "check",
-]
-
 [tasks.ci]
-dependencies = [
-  "fmt",
-  "check",
-  "test",
-  "clippy",
+run_task = [
+    { name = "ci-unix", condition = { platforms = ["linux", "mac"] } },
+    { name = "ci-windows", condition = { platforms = ["windows"] } },
 ]
 
+[tasks.ci-unix]
+private = true
+dependencies = [
+    "fmt",
+    "check-crossterm",
+    "check-termion",
+    "test-crossterm",
+    "test-termion",
+    "clippy-crossterm",
+    "clippy-termion",
+    "test-doc",
+]
+
+[tasks.ci-windows]
+private = true
+dependencies = [
+    "fmt",
+    "check-crossterm",
+    "test-crossterm",
+    "clippy-crossterm",
+    "test-doc",
+]
 
 [tasks.fmt]
 command = "cargo"
@@ -33,8 +39,17 @@ args = [
   "--check",
 ]
 
+[tasks.check-crossterm]
+env = { TUI_FEATURES = "serde,crossterm" }
+run_task = "check"
+
+[tasks.check-termion]
+env = { TUI_FEATURES = "serde,termion" }
+run_task = "check"
+
 [tasks.check]
 command = "cargo"
+condition = { env_set = ["TUI_FEATURES"] }
 args = [
   "check",
   "--no-default-features",
@@ -43,8 +58,17 @@ args = [
   "--all-targets",
 ]
 
+[tasks.build-crossterm]
+env = { TUI_FEATURES = "serde,crossterm" }
+run_task = "build"
+
+[tasks.build-termion]
+env = { TUI_FEATURES = "serde,termion" }
+run_task = "build"
+
 [tasks.build]
 command = "cargo"
+condition = { env_set = ["TUI_FEATURES"] }
 args = [
   "build",
   "--no-default-features",
@@ -53,10 +77,20 @@ args = [
   "--all-targets",
 ]
 
+[tasks.clippy-crossterm]
+env = { TUI_FEATURES = "serde,crossterm" }
+run_task = "clippy"
+
+[tasks.clippy-termion]
+env = { TUI_FEATURES = "serde,termion" }
+run_task = "clippy"
+
 [tasks.clippy]
 command = "cargo"
+condition = { env_set = ["TUI_FEATURES"] }
 args = [
   "clippy",
+  "--all-targets",
   "--no-default-features",
   "--features",
   "${TUI_FEATURES}",
@@ -65,23 +99,17 @@ args = [
   "warnings",
 ]
 
+[tasks.test-crossterm]
+env = { TUI_FEATURES = "serde,crossterm" }
+run_task = "test"
+
+[tasks.test-termion]
+env = { TUI_FEATURES = "serde,termion" }
+run_task = "test"
+
 [tasks.test]
-linux_alias = "test-unix"
-mac_alias = "test-unix"
-windows_alias = "test-windows"
-
-[tasks.test-unix]
-command = "cargo"
-args = [
-  "test",
-  "--no-default-features",
-  "--features",
-  "${TUI_FEATURES}"
-]
-
-# Documentation tests cannot be run on Windows for now
-[tasks.test-windows]
 command = "cargo"
+condition = { env_set = ["TUI_FEATURES"] }
 args = [
   "test",
   "--no-default-features",
@@ -92,39 +120,29 @@ args = [
   "--examples",
 ]
 
+[tasks.test-doc]
+command = "cargo"
+args = [
+  "test",
+  "--doc",
+]
+
 [tasks.run-example]
 private = true
-condition = { env_set = ["TUI_EXAMPLE_NAME", "TUI_FEATURES"] }
+condition = { env_set = ["TUI_EXAMPLE_NAME"] }
 command = "cargo"
 args = [
     "run",
-    "--features",
-    "${TUI_FEATURES}",
     "--release",
     "--example",
     "${TUI_EXAMPLE_NAME}"
 ]
 
-[tasks.run-example-windows]
-private = true
-condition = { env = {"TUI_EXAMPLE_NAME" = "crossterm_demo"} }
-run_task = "run-example"
-
-[tasks.run-example-router]
-private = true
-run_task = [
-    { name = "run-example-windows", condition = { platforms = ["window"] } },
-    { name = "run-example" }
-]
-
 [tasks.build-examples]
-condition = { env_set = ["TUI_FEATURES"] }
 command = "cargo"
 args = [
     "build",
     "--examples",
-    "--features",
-    "${TUI_FEATURES}",
     "--release"
 ]
 
@@ -137,6 +155,6 @@ for file in ${files}
   name = basename ${file}
   name = substring ${name} -3
   set_env TUI_EXAMPLE_NAME ${name}
-  cm_run_task run-example-router
+  cm_run_task run-example
 end
 '''

README.md

@@ -11,15 +11,9 @@ user interfaces and dashboards. It is heavily inspired by the `Javascript`
 library [blessed-contrib](https://github.com/yaronn/blessed-contrib) and the
 `Go` library [termui](https://github.com/gizak/termui).
 
-The library itself supports four different backends to draw to the terminal. You
-can either choose from:
-
+The library supports multiple backends:
+  - [crossterm](https://github.com/crossterm-rs/crossterm) [default]
   - [termion](https://github.com/ticki/termion)
-  - [rustbox](https://github.com/gchp/rustbox)
-  - [crossterm](https://github.com/crossterm-rs/crossterm)
-  - [pancurses](https://github.com/ihalila/pancurses)
-
-However, some features may only be available in one of the four.
 
 The library is based on the principle of immediate rendering with intermediate
 buffers. This means that at each new frame you should build all widgets that are
@@ -34,18 +28,19 @@ you may rely on the previously cited libraries to achieve such features.
 
 ### Rust version requirements
 
-Since version 0.10.0, `tui` requires **rustc version 1.44.0 or greater**.
+Since version 0.17.0, `tui` requires **rustc version 1.52.1 or greater**.
 
 ### [Documentation](https://docs.rs/tui)
 
 ### Demo
 
-The demo shown in the gif can be run with all available backends
-(`examples/*_demo.rs` files). For example to see the `termion` version one could
-run:
+The demo shown in the gif can be run with all available backends.
 
 ```
-cargo run --example termion_demo --release -- --tick-rate 200
+# crossterm
+cargo run --example demo --release -- --tick-rate 200
+# termion
+cargo run --example demo --no-default-features --features=termion --release -- --tick-rate 200
 ```
 
 where `tick-rate` is the UI refresh rate in ms.
@@ -53,18 +48,11 @@ where `tick-rate` is the UI refresh rate in ms.
 The UI code is in [examples/demo/ui.rs](https://github.com/fdehau/tui-rs/blob/v0.16.0/examples/demo/ui.rs) while the
 application state is in [examples/demo/app.rs](https://github.com/fdehau/tui-rs/blob/v0.16.0/examples/demo/app.rs).
 
-Beware that the `termion_demo` only works on Unix platforms. If you are a Windows user,
-you can see the same demo using the `crossterm` backend with the following command:
-
-```
-cargo run --example crossterm_demo --no-default-features --features="crossterm" --release -- --tick-rate 200
-```
-
 If the user interface contains glyphs that are not displayed correctly by your terminal, you may want to run
 the demo without those symbols:
 
 ```
-cargo run --example crossterm_demo --no-default-features --features="crossterm" --release -- --tick-rate 200 --enhanced-graphics false
+cargo run --example demo --release -- --tick-rate 200 --enhanced-graphics false
 ```
 
 ### Widgets
@@ -83,9 +71,10 @@ The library comes with the following list of widgets:
   * [Tabs](https://github.com/fdehau/tui-rs/blob/v0.16.0/examples/tabs.rs)
 
 Click on each item to see the source of the example. Run the examples with with 
-cargo (e.g. to run the demo `cargo run --example demo`), and quit by pressing `q`.
+cargo (e.g. to run the gauge example `cargo run --example gauge`), and quit by pressing `q`.
 
-You can run all examples by running `make run-examples`.
+You can run all examples by running `cargo make run-examples` (require
+`cargo-make` that can be installed with `cargo install cargo-make`).
 
 ### Third-party widgets
 
@@ -116,6 +105,9 @@ You can run all examples by running `make run-examples`.
 * [minesweep](https://github.com/cpcloud/minesweep-rs)
 * [Battleship.rs](https://github.com/deepu105/battleship-rs)
 * [termscp](https://github.com/veeso/termscp)
+* [joshuto](https://github.com/kamiyaa/joshuto)
+* [adsb_deku/radar](https://github.com/wcampbell0x2a/adsb_deku#radar-tui)
+* [hoard](https://github.com/Hyde46/hoard)
 
 ### Alternatives
 

examples/barchart.rs

@@ -1,15 +1,19 @@
-#[allow(dead_code)]
-mod util;
-
-use crate::util::event::{Event, Events};
-use std::{error::Error, io};
-use termion::{event::Key, input::MouseTerminal, raw::IntoRawMode, screen::AlternateScreen};
+use crossterm::{
+    event::{self, DisableMouseCapture, EnableMouseCapture, Event, KeyCode},
+    execute,
+    terminal::{disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen},
+};
+use std::{
+    error::Error,
+    io,
+    time::{Duration, Instant},
+};
 use tui::{
-    backend::TermionBackend,
+    backend::{Backend, CrosstermBackend},
     layout::{Constraint, Direction, Layout},
     style::{Color, Modifier, Style},
     widgets::{BarChart, Block, Borders},
-    Terminal,
+    Frame, Terminal,
 };
 
 struct App<'a> {
@@ -48,85 +52,110 @@ impl<'a> App<'a> {
         }
     }
 
-    fn update(&mut self) {
+    fn on_tick(&mut self) {
         let value = self.data.pop().unwrap();
         self.data.insert(0, value);
     }
 }
 
 fn main() -> Result<(), Box<dyn Error>> {
-    // Terminal initialization
-    let stdout = io::stdout().into_raw_mode()?;
-    let stdout = MouseTerminal::from(stdout);
-    let stdout = AlternateScreen::from(stdout);
-    let backend = TermionBackend::new(stdout);
+    // setup terminal
+    enable_raw_mode()?;
+    let mut stdout = io::stdout();
+    execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
+    let backend = CrosstermBackend::new(stdout);
     let mut terminal = Terminal::new(backend)?;
 
-    // Setup event handlers
-    let events = Events::new();
+    // create app and run it
+    let tick_rate = Duration::from_millis(250);
+    let app = App::new();
+    let res = run_app(&mut terminal, app, tick_rate);
 
-    // App
-    let mut app = App::new();
+    // restore terminal
+    disable_raw_mode()?;
+    execute!(
+        terminal.backend_mut(),
+        LeaveAlternateScreen,
+        DisableMouseCapture
+    )?;
+    terminal.show_cursor()?;
 
-    loop {
-        terminal.draw(|f| {
-            let chunks = Layout::default()
-                .direction(Direction::Vertical)
-                .margin(2)
-                .constraints([Constraint::Percentage(50), Constraint::Percentage(50)].as_ref())
-                .split(f.size());
-            let barchart = BarChart::default()
-                .block(Block::default().title("Data1").borders(Borders::ALL))
-                .data(&app.data)
-                .bar_width(9)
-                .bar_style(Style::default().fg(Color::Yellow))
-                .value_style(Style::default().fg(Color::Black).bg(Color::Yellow));
-            f.render_widget(barchart, chunks[0]);
-
-            let chunks = Layout::default()
-                .direction(Direction::Horizontal)
-                .constraints([Constraint::Percentage(50), Constraint::Percentage(50)].as_ref())
-                .split(chunks[1]);
-
-            let barchart = BarChart::default()
-                .block(Block::default().title("Data2").borders(Borders::ALL))
-                .data(&app.data)
-                .bar_width(5)
-                .bar_gap(3)
-                .bar_style(Style::default().fg(Color::Green))
-                .value_style(
-                    Style::default()
-                        .bg(Color::Green)
-                        .add_modifier(Modifier::BOLD),
-                );
-            f.render_widget(barchart, chunks[0]);
-
-            let barchart = BarChart::default()
-                .block(Block::default().title("Data3").borders(Borders::ALL))
-                .data(&app.data)
-                .bar_style(Style::default().fg(Color::Red))
-                .bar_width(7)
-                .bar_gap(0)
-                .value_style(Style::default().bg(Color::Red))
-                .label_style(
-                    Style::default()
-                        .fg(Color::Cyan)
-                        .add_modifier(Modifier::ITALIC),
-                );
-            f.render_widget(barchart, chunks[1]);
-        })?;
-
-        match events.next()? {
-            Event::Input(input) => {
-                if input == Key::Char('q') {
-                    break;
-                }
-            }
-            Event::Tick => {
-                app.update();
-            }
-        }
+    if let Err(err) = res {
+        println!("{:?}", err)
     }
 
     Ok(())
 }
+
+fn run_app<B: Backend>(
+    terminal: &mut Terminal<B>,
+    mut app: App,
+    tick_rate: Duration,
+) -> io::Result<()> {
+    let mut last_tick = Instant::now();
+    loop {
+        terminal.draw(|f| ui(f, &app))?;
+
+        let timeout = tick_rate
+            .checked_sub(last_tick.elapsed())
+            .unwrap_or_else(|| Duration::from_secs(0));
+        if crossterm::event::poll(timeout)? {
+            if let Event::Key(key) = event::read()? {
+                if let KeyCode::Char('q') = key.code {
+                    return Ok(());
+                }
+            }
+        }
+        if last_tick.elapsed() >= tick_rate {
+            app.on_tick();
+            last_tick = Instant::now();
+        }
+    }
+}
+
+fn ui<B: Backend>(f: &mut Frame<B>, app: &App) {
+    let chunks = Layout::default()
+        .direction(Direction::Vertical)
+        .margin(2)
+        .constraints([Constraint::Percentage(50), Constraint::Percentage(50)].as_ref())
+        .split(f.size());
+    let barchart = BarChart::default()
+        .block(Block::default().title("Data1").borders(Borders::ALL))
+        .data(&app.data)
+        .bar_width(9)
+        .bar_style(Style::default().fg(Color::Yellow))
+        .value_style(Style::default().fg(Color::Black).bg(Color::Yellow));
+    f.render_widget(barchart, chunks[0]);
+
+    let chunks = Layout::default()
+        .direction(Direction::Horizontal)
+        .constraints([Constraint::Percentage(50), Constraint::Percentage(50)].as_ref())
+        .split(chunks[1]);
+
+    let barchart = BarChart::default()
+        .block(Block::default().title("Data2").borders(Borders::ALL))
+        .data(&app.data)
+        .bar_width(5)
+        .bar_gap(3)
+        .bar_style(Style::default().fg(Color::Green))
+        .value_style(
+            Style::default()
+                .bg(Color::Green)
+                .add_modifier(Modifier::BOLD),
+        );
+    f.render_widget(barchart, chunks[0]);
+
+    let barchart = BarChart::default()
+        .block(Block::default().title("Data3").borders(Borders::ALL))
+        .data(&app.data)
+        .bar_style(Style::default().fg(Color::Red))
+        .bar_width(7)
+        .bar_gap(0)
+        .value_style(Style::default().bg(Color::Red))
+        .label_style(
+            Style::default()
+                .fg(Color::Cyan)
+                .add_modifier(Modifier::ITALIC),
+        );
+    f.render_widget(barchart, chunks[1]);
+}

examples/block.rs

@@ -1,101 +1,119 @@
-#[allow(dead_code)]
-mod util;
-
-use crate::util::event::{Event, Events};
+use crossterm::{
+    event::{self, DisableMouseCapture, EnableMouseCapture, Event, KeyCode},
+    execute,
+    terminal::{disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen},
+};
 use std::{error::Error, io};
-use termion::{event::Key, input::MouseTerminal, raw::IntoRawMode, screen::AlternateScreen};
 use tui::{
-    backend::TermionBackend,
+    backend::{Backend, CrosstermBackend},
     layout::{Alignment, Constraint, Direction, Layout},
     style::{Color, Modifier, Style},
     text::Span,
     widgets::{Block, BorderType, Borders},
-    Terminal,
+    Frame, Terminal,
 };
 
 fn main() -> Result<(), Box<dyn Error>> {
-    // Terminal initialization
-    let stdout = io::stdout().into_raw_mode()?;
-    let stdout = MouseTerminal::from(stdout);
-    let stdout = AlternateScreen::from(stdout);
-    let backend = TermionBackend::new(stdout);
+    // setup terminal
+    enable_raw_mode()?;
+    let mut stdout = io::stdout();
+    execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
+    let backend = CrosstermBackend::new(stdout);
     let mut terminal = Terminal::new(backend)?;
 
-    // Setup event handlers
-    let events = Events::new();
+    // create app and run it
+    let res = run_app(&mut terminal);
 
+    // restore terminal
+    disable_raw_mode()?;
+    execute!(
+        terminal.backend_mut(),
+        LeaveAlternateScreen,
+        DisableMouseCapture
+    )?;
+    terminal.show_cursor()?;
+
+    if let Err(err) = res {
+        println!("{:?}", err)
+    }
+
+    Ok(())
+}
+
+fn run_app<B: Backend>(terminal: &mut Terminal<B>) -> io::Result<()> {
     loop {
-        terminal.draw(|f| {
-            // Wrapping block for a group
-            // Just draw the block and the group on the same area and build the group
-            // with at least a margin of 1
-            let size = f.size();
+        terminal.draw(ui)?;
 
-            // Surrounding block
-            let block = Block::default()
-                .borders(Borders::ALL)
-                .title("Main block with round corners")
-                .title_alignment(Alignment::Center)
-                .border_type(BorderType::Rounded);
-            f.render_widget(block, size);
-
-            let chunks = Layout::default()
-                .direction(Direction::Vertical)
-                .margin(4)
-                .constraints([Constraint::Percentage(50), Constraint::Percentage(50)].as_ref())
-                .split(f.size());
-
-            // Top two inner blocks
-            let top_chunks = Layout::default()
-                .direction(Direction::Horizontal)
-                .constraints([Constraint::Percentage(50), Constraint::Percentage(50)].as_ref())
-                .split(chunks[0]);
-
-            // Top left inner block with green background
-            let block = Block::default()
-                .title(vec![
-                    Span::styled("With", Style::default().fg(Color::Yellow)),
-                    Span::from(" background"),
-                ])
-                .style(Style::default().bg(Color::Green));
-            f.render_widget(block, top_chunks[0]);
-
-            // Top right inner block with styled title aligned to the right
-            let block = Block::default()
-                .title(Span::styled(
-                    "Styled title",
-                    Style::default()
-                        .fg(Color::White)
-                        .bg(Color::Red)
-                        .add_modifier(Modifier::BOLD),
-                ))
-                .title_alignment(Alignment::Right);
-            f.render_widget(block, top_chunks[1]);
-
-            // Bottom two inner blocks
-            let bottom_chunks = Layout::default()
-                .direction(Direction::Horizontal)
-                .constraints([Constraint::Percentage(50), Constraint::Percentage(50)].as_ref())
-                .split(chunks[1]);
-
-            // Bottom left block with all default borders
-            let block = Block::default().title("With borders").borders(Borders::ALL);
-            f.render_widget(block, bottom_chunks[0]);
-
-            // Bottom right block with styled left and right border
-            let block = Block::default()
-                .title("With styled borders and doubled borders")
-                .border_style(Style::default().fg(Color::Cyan))
-                .borders(Borders::LEFT | Borders::RIGHT)
-                .border_type(BorderType::Double);
-            f.render_widget(block, bottom_chunks[1]);
-        })?;
-
-        if let Event::Input(key) = events.next()? {
-            if key == Key::Char('q') {
-                break;
+        if let Event::Key(key) = event::read()? {
+            if let KeyCode::Char('q') = key.code {
+                return Ok(());
             }
         }
     }
-    Ok(())
+}
+
+fn ui<B: Backend>(f: &mut Frame<B>) {
+    // Wrapping block for a group
+    // Just draw the block and the group on the same area and build the group
+    // with at least a margin of 1
+    let size = f.size();
+
+    // Surrounding block
+    let block = Block::default()
+        .borders(Borders::ALL)
+        .title("Main block with round corners")
+        .title_alignment(Alignment::Center)
+        .border_type(BorderType::Rounded);
+    f.render_widget(block, size);
+
+    let chunks = Layout::default()
+        .direction(Direction::Vertical)
+        .margin(4)
+        .constraints([Constraint::Percentage(50), Constraint::Percentage(50)].as_ref())
+        .split(f.size());
+
+    // Top two inner blocks
+    let top_chunks = Layout::default()
+        .direction(Direction::Horizontal)
+        .constraints([Constraint::Percentage(50), Constraint::Percentage(50)].as_ref())
+        .split(chunks[0]);
+
+    // Top left inner block with green background
+    let block = Block::default()
+        .title(vec![
+            Span::styled("With", Style::default().fg(Color::Yellow)),
+            Span::from(" background"),
+        ])
+        .style(Style::default().bg(Color::Green));
+    f.render_widget(block, top_chunks[0]);
+
+    // Top right inner block with styled title aligned to the right
+    let block = Block::default()
+        .title(Span::styled(
+            "Styled title",
+            Style::default()
+                .fg(Color::White)
+                .bg(Color::Red)
+                .add_modifier(Modifier::BOLD),
+        ))
+        .title_alignment(Alignment::Right);
+    f.render_widget(block, top_chunks[1]);
+
+    // Bottom two inner blocks
+    let bottom_chunks = Layout::default()
+        .direction(Direction::Horizontal)
+        .constraints([Constraint::Percentage(50), Constraint::Percentage(50)].as_ref())
+        .split(chunks[1]);
+
+    // Bottom left block with all default borders
+    let block = Block::default().title("With borders").borders(Borders::ALL);
+    f.render_widget(block, bottom_chunks[0]);
+
+    // Bottom right block with styled left and right border
+    let block = Block::default()
+        .title("With styled borders and doubled borders")
+        .border_style(Style::default().fg(Color::Cyan))
+        .borders(Borders::LEFT | Borders::RIGHT)
+        .border_type(BorderType::Double);
+    f.render_widget(block, bottom_chunks[1]);
 }

examples/canvas.rs

@@ -1,18 +1,23 @@
-#[allow(dead_code)]
-mod util;
-
-use crate::util::event::{Config, Event, Events};
-use std::{error::Error, io, time::Duration};
-use termion::{event::Key, input::MouseTerminal, raw::IntoRawMode, screen::AlternateScreen};
+use crossterm::{
+    event::{self, DisableMouseCapture, EnableMouseCapture, Event, KeyCode},
+    execute,
+    terminal::{disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen},
+};
+use std::{
+    error::Error,
+    io,
+    time::{Duration, Instant},
+};
 use tui::{
-    backend::TermionBackend,
+    backend::{Backend, CrosstermBackend},
     layout::{Constraint, Direction, Layout, Rect},
-    style::Color,
+    style::{Color, Style},
+    text::Span,
     widgets::{
         canvas::{Canvas, Map, MapResolution, Rectangle},
         Block, Borders,
     },
-    Terminal,
+    Frame, Terminal,
 };
 
 struct App {
@@ -46,7 +51,7 @@ impl App {
         }
     }
 
-    fn update(&mut self) {
+    fn on_tick(&mut self) {
         if self.ball.x < self.playground.left() as f64
             || self.ball.x + self.ball.width > self.playground.right() as f64
         {
@@ -73,76 +78,103 @@ impl App {
 }
 
 fn main() -> Result<(), Box<dyn Error>> {
-    // Terminal initialization
-    let stdout = io::stdout().into_raw_mode()?;
-    let stdout = MouseTerminal::from(stdout);
-    let stdout = AlternateScreen::from(stdout);
-    let backend = TermionBackend::new(stdout);
+    // setup terminal
+    enable_raw_mode()?;
+    let mut stdout = io::stdout();
+    execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
+    let backend = CrosstermBackend::new(stdout);
     let mut terminal = Terminal::new(backend)?;
 
-    // Setup event handlers
-    let config = Config {
-        tick_rate: Duration::from_millis(250),
-        ..Default::default()
-    };
-    let events = Events::with_config(config);
+    // create app and run it
+    let tick_rate = Duration::from_millis(250);
+    let app = App::new();
+    let res = run_app(&mut terminal, app, tick_rate);
 
-    // App
-    let mut app = App::new();
+    // restore terminal
+    disable_raw_mode()?;
+    execute!(
+        terminal.backend_mut(),
+        LeaveAlternateScreen,
+        DisableMouseCapture
+    )?;
+    terminal.show_cursor()?;
 
-    loop {
-        terminal.draw(|f| {
-            let chunks = Layout::default()
-                .direction(Direction::Horizontal)
-                .constraints([Constraint::Percentage(50), Constraint::Percentage(50)].as_ref())
-                .split(f.size());
-            let canvas = Canvas::default()
-                .block(Block::default().borders(Borders::ALL).title("World"))
-                .paint(|ctx| {
-                    ctx.draw(&Map {
-                        color: Color::White,
-                        resolution: MapResolution::High,
-                    });
-                    ctx.print(app.x, -app.y, "You are here", Color::Yellow);
-                })
-                .x_bounds([-180.0, 180.0])
-                .y_bounds([-90.0, 90.0]);
-            f.render_widget(canvas, chunks[0]);
-            let canvas = Canvas::default()
-                .block(Block::default().borders(Borders::ALL).title("Pong"))
-                .paint(|ctx| {
-                    ctx.draw(&app.ball);
-                })
-                .x_bounds([10.0, 110.0])
-                .y_bounds([10.0, 110.0]);
-            f.render_widget(canvas, chunks[1]);
-        })?;
-
-        match events.next()? {
-            Event::Input(input) => match input {
-                Key::Char('q') => {
-                    break;
-                }
-                Key::Down => {
-                    app.y += 1.0;
-                }
-                Key::Up => {
-                    app.y -= 1.0;
-                }
-                Key::Right => {
-                    app.x += 1.0;
-                }
-                Key::Left => {
-                    app.x -= 1.0;
-                }
-
-                _ => {}
-            },
-            Event::Tick => {
-                app.update();
-            }
-        }
+    if let Err(err) = res {
+        println!("{:?}", err)
     }
 
     Ok(())
 }
+
+fn run_app<B: Backend>(
+    terminal: &mut Terminal<B>,
+    mut app: App,
+    tick_rate: Duration,
+) -> io::Result<()> {
+    let mut last_tick = Instant::now();
+    loop {
+        terminal.draw(|f| ui(f, &app))?;
+
+        let timeout = tick_rate
+            .checked_sub(last_tick.elapsed())
+            .unwrap_or_else(|| Duration::from_secs(0));
+        if event::poll(timeout)? {
+            if let Event::Key(key) = event::read()? {
+                match key.code {
+                    KeyCode::Char('q') => {
+                        return Ok(());
+                    }
+                    KeyCode::Down => {
+                        app.y += 1.0;
+                    }
+                    KeyCode::Up => {
+                        app.y -= 1.0;
+                    }
+                    KeyCode::Right => {
+                        app.x += 1.0;
+                    }
+                    KeyCode::Left => {
+                        app.x -= 1.0;
+                    }
+                    _ => {}
+                }
+            }
+        }
+
+        if last_tick.elapsed() >= tick_rate {
+            app.on_tick();
+            last_tick = Instant::now();
+        }
+    }
+}
+
+fn ui<B: Backend>(f: &mut Frame<B>, app: &App) {
+    let chunks = Layout::default()
+        .direction(Direction::Horizontal)
+        .constraints([Constraint::Percentage(50), Constraint::Percentage(50)].as_ref())
+        .split(f.size());
+    let canvas = Canvas::default()
+        .block(Block::default().borders(Borders::ALL).title("World"))
+        .paint(|ctx| {
+            ctx.draw(&Map {
+                color: Color::White,
+                resolution: MapResolution::High,
+            });
+            ctx.print(
+                app.x,
+                -app.y,
+                Span::styled("You are here", Style::default().fg(Color::Yellow)),
+            );
+        })
+        .x_bounds([-180.0, 180.0])
+        .y_bounds([-90.0, 90.0]);
+    f.render_widget(canvas, chunks[0]);
+    let canvas = Canvas::default()
+        .block(Block::default().borders(Borders::ALL).title("Pong"))
+        .paint(|ctx| {
+            ctx.draw(&app.ball);
+        })
+        .x_bounds([10.0, 110.0])
+        .y_bounds([10.0, 110.0]);
+    f.render_widget(canvas, chunks[1]);
+}

examples/chart.rs

@@ -1,20 +1,21 @@
-#[allow(dead_code)]
-mod util;
-
-use crate::util::{
-    event::{Event, Events},
-    SinSignal,
+use crossterm::{
+    event::{self, DisableMouseCapture, EnableMouseCapture, Event, KeyCode},
+    execute,
+    terminal::{disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen},
+};
+use std::{
+    error::Error,
+    io,
+    time::{Duration, Instant},
 };
-use std::{error::Error, io};
-use termion::{event::Key, input::MouseTerminal, raw::IntoRawMode, screen::AlternateScreen};
 use tui::{
-    backend::TermionBackend,
+    backend::{Backend, CrosstermBackend},
     layout::{Constraint, Direction, Layout},
     style::{Color, Modifier, Style},
     symbols,
     text::Span,
     widgets::{Axis, Block, Borders, Chart, Dataset, GraphType},
-    Terminal,
+    Frame, Terminal,
 };
 
 const DATA: [(f64, f64); 5] = [(0.0, 0.0), (1.0, 1.0), (2.0, 2.0), (3.0, 3.0), (4.0, 4.0)];
@@ -28,6 +29,34 @@ const DATA2: [(f64, f64); 7] = [
     (60.0, 3.0),
 ];
 
+#[derive(Clone)]
+pub struct SinSignal {
+    x: f64,
+    interval: f64,
+    period: f64,
+    scale: f64,
+}
+
+impl SinSignal {
+    pub fn new(interval: f64, period: f64, scale: f64) -> SinSignal {
+        SinSignal {
+            x: 0.0,
+            interval,
+            period,
+            scale,
+        }
+    }
+}
+
+impl Iterator for SinSignal {
+    type Item = (f64, f64);
+    fn next(&mut self) -> Option<Self::Item> {
+        let point = (self.x, (self.x * 1.0 / self.period).sin() * self.scale);
+        self.x += self.interval;
+        Some(point)
+    }
+}
+
 struct App {
     signal1: SinSignal,
     data1: Vec<(f64, f64)>,
@@ -51,7 +80,7 @@ impl App {
         }
     }
 
-    fn update(&mut self) {
+    fn on_tick(&mut self) {
         for _ in 0..5 {
             self.data1.remove(0);
         }
@@ -66,181 +95,207 @@ impl App {
 }
 
 fn main() -> Result<(), Box<dyn Error>> {
-    // Terminal initialization
-    let stdout = io::stdout().into_raw_mode()?;
-    let stdout = MouseTerminal::from(stdout);
-    let stdout = AlternateScreen::from(stdout);
-    let backend = TermionBackend::new(stdout);
+    // setup terminal
+    enable_raw_mode()?;
+    let mut stdout = io::stdout();
+    execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
+    let backend = CrosstermBackend::new(stdout);
     let mut terminal = Terminal::new(backend)?;
 
-    let events = Events::new();
+    // create app and run it
+    let tick_rate = Duration::from_millis(250);
+    let app = App::new();
+    let res = run_app(&mut terminal, app, tick_rate);
 
-    // App
-    let mut app = App::new();
+    // restore terminal
+    disable_raw_mode()?;
+    execute!(
+        terminal.backend_mut(),
+        LeaveAlternateScreen,
+        DisableMouseCapture
+    )?;
+    terminal.show_cursor()?;
 
-    loop {
-        terminal.draw(|f| {
-            let size = f.size();
-            let chunks = Layout::default()
-                .direction(Direction::Vertical)
-                .constraints(
-                    [
-                        Constraint::Ratio(1, 3),
-                        Constraint::Ratio(1, 3),
-                        Constraint::Ratio(1, 3),
-                    ]
-                    .as_ref(),
-                )
-                .split(size);
-            let x_labels = vec![
-                Span::styled(
-                    format!("{}", app.window[0]),
-                    Style::default().add_modifier(Modifier::BOLD),
-                ),
-                Span::raw(format!("{}", (app.window[0] + app.window[1]) / 2.0)),
-                Span::styled(
-                    format!("{}", app.window[1]),
-                    Style::default().add_modifier(Modifier::BOLD),
-                ),
-            ];
-            let datasets = vec![
-                Dataset::default()
-                    .name("data2")
-                    .marker(symbols::Marker::Dot)
-                    .style(Style::default().fg(Color::Cyan))
-                    .data(&app.data1),
-                Dataset::default()
-                    .name("data3")
-                    .marker(symbols::Marker::Braille)
-                    .style(Style::default().fg(Color::Yellow))
-                    .data(&app.data2),
-            ];
-
-            let chart = Chart::new(datasets)
-                .block(
-                    Block::default()
-                        .title(Span::styled(
-                            "Chart 1",
-                            Style::default()
-                                .fg(Color::Cyan)
-                                .add_modifier(Modifier::BOLD),
-                        ))
-                        .borders(Borders::ALL),
-                )
-                .x_axis(
-                    Axis::default()
-                        .title("X Axis")
-                        .style(Style::default().fg(Color::Gray))
-                        .labels(x_labels)
-                        .bounds(app.window),
-                )
-                .y_axis(
-                    Axis::default()
-                        .title("Y Axis")
-                        .style(Style::default().fg(Color::Gray))
-                        .labels(vec![
-                            Span::styled("-20", Style::default().add_modifier(Modifier::BOLD)),
-                            Span::raw("0"),
-                            Span::styled("20", Style::default().add_modifier(Modifier::BOLD)),
-                        ])
-                        .bounds([-20.0, 20.0]),
-                );
-            f.render_widget(chart, chunks[0]);
-
-            let datasets = vec![Dataset::default()
-                .name("data")
-                .marker(symbols::Marker::Braille)
-                .style(Style::default().fg(Color::Yellow))
-                .graph_type(GraphType::Line)
-                .data(&DATA)];
-            let chart = Chart::new(datasets)
-                .block(
-                    Block::default()
-                        .title(Span::styled(
-                            "Chart 2",
-                            Style::default()
-                                .fg(Color::Cyan)
-                                .add_modifier(Modifier::BOLD),
-                        ))
-                        .borders(Borders::ALL),
-                )
-                .x_axis(
-                    Axis::default()
-                        .title("X Axis")
-                        .style(Style::default().fg(Color::Gray))
-                        .bounds([0.0, 5.0])
-                        .labels(vec![
-                            Span::styled("0", Style::default().add_modifier(Modifier::BOLD)),
-                            Span::raw("2.5"),
-                            Span::styled("5.0", Style::default().add_modifier(Modifier::BOLD)),
-                        ]),
-                )
-                .y_axis(
-                    Axis::default()
-                        .title("Y Axis")
-                        .style(Style::default().fg(Color::Gray))
-                        .bounds([0.0, 5.0])
-                        .labels(vec![
-                            Span::styled("0", Style::default().add_modifier(Modifier::BOLD)),
-                            Span::raw("2.5"),
-                            Span::styled("5.0", Style::default().add_modifier(Modifier::BOLD)),
-                        ]),
-                );
-            f.render_widget(chart, chunks[1]);
-
-            let datasets = vec![Dataset::default()
-                .name("data")
-                .marker(symbols::Marker::Braille)
-                .style(Style::default().fg(Color::Yellow))
-                .graph_type(GraphType::Line)
-                .data(&DATA2)];
-            let chart = Chart::new(datasets)
-                .block(
-                    Block::default()
-                        .title(Span::styled(
-                            "Chart 3",
-                            Style::default()
-                                .fg(Color::Cyan)
-                                .add_modifier(Modifier::BOLD),
-                        ))
-                        .borders(Borders::ALL),
-                )
-                .x_axis(
-                    Axis::default()
-                        .title("X Axis")
-                        .style(Style::default().fg(Color::Gray))
-                        .bounds([0.0, 50.0])
-                        .labels(vec![
-                            Span::styled("0", Style::default().add_modifier(Modifier::BOLD)),
-                            Span::raw("25"),
-                            Span::styled("50", Style::default().add_modifier(Modifier::BOLD)),
-                        ]),
-                )
-                .y_axis(
-                    Axis::default()
-                        .title("Y Axis")
-                        .style(Style::default().fg(Color::Gray))
-                        .bounds([0.0, 5.0])
-                        .labels(vec![
-                            Span::styled("0", Style::default().add_modifier(Modifier::BOLD)),
-                            Span::raw("2.5"),
-                            Span::styled("5", Style::default().add_modifier(Modifier::BOLD)),
-                        ]),
-                );
-            f.render_widget(chart, chunks[2]);
-        })?;
-
-        match events.next()? {
-            Event::Input(input) => {
-                if input == Key::Char('q') {
-                    break;
-                }
-            }
-            Event::Tick => {
-                app.update();
-            }
-        }
+    if let Err(err) = res {
+        println!("{:?}", err)
     }
 
     Ok(())
 }
+
+fn run_app<B: Backend>(
+    terminal: &mut Terminal<B>,
+    mut app: App,
+    tick_rate: Duration,
+) -> io::Result<()> {
+    let mut last_tick = Instant::now();
+    loop {
+        terminal.draw(|f| ui(f, &app))?;
+
+        let timeout = tick_rate
+            .checked_sub(last_tick.elapsed())
+            .unwrap_or_else(|| Duration::from_secs(0));
+        if crossterm::event::poll(timeout)? {
+            if let Event::Key(key) = event::read()? {
+                if let KeyCode::Char('q') = key.code {
+                    return Ok(());
+                }
+            }
+        }
+        if last_tick.elapsed() >= tick_rate {
+            app.on_tick();
+            last_tick = Instant::now();
+        }
+    }
+}
+
+fn ui<B: Backend>(f: &mut Frame<B>, app: &App) {
+    let size = f.size();
+    let chunks = Layout::default()
+        .direction(Direction::Vertical)
+        .constraints(
+            [
+                Constraint::Ratio(1, 3),
+                Constraint::Ratio(1, 3),
+                Constraint::Ratio(1, 3),
+            ]
+            .as_ref(),
+        )
+        .split(size);
+    let x_labels = vec![
+        Span::styled(
+            format!("{}", app.window[0]),
+            Style::default().add_modifier(Modifier::BOLD),
+        ),
+        Span::raw(format!("{}", (app.window[0] + app.window[1]) / 2.0)),
+        Span::styled(
+            format!("{}", app.window[1]),
+            Style::default().add_modifier(Modifier::BOLD),
+        ),
+    ];
+    let datasets = vec![
+        Dataset::default()
+            .name("data2")
+            .marker(symbols::Marker::Dot)
+            .style(Style::default().fg(Color::Cyan))
+            .data(&app.data1),
+        Dataset::default()
+            .name("data3")
+            .marker(symbols::Marker::Braille)
+            .style(Style::default().fg(Color::Yellow))
+            .data(&app.data2),
+    ];
+
+    let chart = Chart::new(datasets)
+        .block(
+            Block::default()
+                .title(Span::styled(
+                    "Chart 1",
+                    Style::default()
+                        .fg(Color::Cyan)
+                        .add_modifier(Modifier::BOLD),
+                ))
+                .borders(Borders::ALL),
+        )
+        .x_axis(
+            Axis::default()
+                .title("X Axis")
+                .style(Style::default().fg(Color::Gray))
+                .labels(x_labels)
+                .bounds(app.window),
+        )
+        .y_axis(
+            Axis::default()
+                .title("Y Axis")
+                .style(Style::default().fg(Color::Gray))
+                .labels(vec![
+                    Span::styled("-20", Style::default().add_modifier(Modifier::BOLD)),
+                    Span::raw("0"),
+                    Span::styled("20", Style::default().add_modifier(Modifier::BOLD)),
+                ])
+                .bounds([-20.0, 20.0]),
+        );
+    f.render_widget(chart, chunks[0]);
+
+    let datasets = vec![Dataset::default()
+        .name("data")
+        .marker(symbols::Marker::Braille)
+        .style(Style::default().fg(Color::Yellow))
+        .graph_type(GraphType::Line)
+        .data(&DATA)];
+    let chart = Chart::new(datasets)
+        .block(
+            Block::default()
+                .title(Span::styled(
+                    "Chart 2",
+                    Style::default()
+                        .fg(Color::Cyan)
+                        .add_modifier(Modifier::BOLD),
+                ))
+                .borders(Borders::ALL),
+        )
+        .x_axis(
+            Axis::default()
+                .title("X Axis")
+                .style(Style::default().fg(Color::Gray))
+                .bounds([0.0, 5.0])
+                .labels(vec![
+                    Span::styled("0", Style::default().add_modifier(Modifier::BOLD)),
+                    Span::raw("2.5"),
+                    Span::styled("5.0", Style::default().add_modifier(Modifier::BOLD)),
+                ]),
+        )
+        .y_axis(
+            Axis::default()
+                .title("Y Axis")
+                .style(Style::default().fg(Color::Gray))
+                .bounds([0.0, 5.0])
+                .labels(vec![
+                    Span::styled("0", Style::default().add_modifier(Modifier::BOLD)),
+                    Span::raw("2.5"),
+                    Span::styled("5.0", Style::default().add_modifier(Modifier::BOLD)),
+                ]),
+        );
+    f.render_widget(chart, chunks[1]);
+
+    let datasets = vec![Dataset::default()
+        .name("data")
+        .marker(symbols::Marker::Braille)
+        .style(Style::default().fg(Color::Yellow))
+        .graph_type(GraphType::Line)
+        .data(&DATA2)];
+    let chart = Chart::new(datasets)
+        .block(
+            Block::default()
+                .title(Span::styled(
+                    "Chart 3",
+                    Style::default()
+                        .fg(Color::Cyan)
+                        .add_modifier(Modifier::BOLD),
+                ))
+                .borders(Borders::ALL),
+        )
+        .x_axis(
+            Axis::default()
+                .title("X Axis")
+                .style(Style::default().fg(Color::Gray))
+                .bounds([0.0, 50.0])
+                .labels(vec![
+                    Span::styled("0", Style::default().add_modifier(Modifier::BOLD)),
+                    Span::raw("25"),
+                    Span::styled("50", Style::default().add_modifier(Modifier::BOLD)),
+                ]),
+        )
+        .y_axis(
+            Axis::default()
+                .title("Y Axis")
+                .style(Style::default().fg(Color::Gray))
+                .bounds([0.0, 5.0])
+                .labels(vec![
+                    Span::styled("0", Style::default().add_modifier(Modifier::BOLD)),
+                    Span::raw("2.5"),
+                    Span::styled("5", Style::default().add_modifier(Modifier::BOLD)),
+                ]),
+        );
+    f.render_widget(chart, chunks[2]);
+}

examples/crossterm_demo.rs

@@ -1,108 +0,0 @@
-#[allow(dead_code)]
-mod demo;
-#[allow(dead_code)]
-mod util;
-
-use crate::demo::{ui, App};
-use argh::FromArgs;
-use crossterm::{
-    event::{self, DisableMouseCapture, EnableMouseCapture, Event as CEvent, KeyCode},
-    execute,
-    terminal::{disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen},
-};
-use std::{
-    error::Error,
-    io::stdout,
-    sync::mpsc,
-    thread,
-    time::{Duration, Instant},
-};
-use tui::{backend::CrosstermBackend, Terminal};
-
-enum Event<I> {
-    Input(I),
-    Tick,
-}
-
-/// Crossterm demo
-#[derive(Debug, FromArgs)]
-struct Cli {
-    /// time in ms between two ticks.
-    #[argh(option, default = "250")]
-    tick_rate: u64,
-    /// whether unicode symbols are used to improve the overall look of the app
-    #[argh(option, default = "true")]
-    enhanced_graphics: bool,
-}
-
-fn main() -> Result<(), Box<dyn Error>> {
-    let cli: Cli = argh::from_env();
-
-    enable_raw_mode()?;
-
-    let mut stdout = stdout();
-    execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
-
-    let backend = CrosstermBackend::new(stdout);
-
-    let mut terminal = Terminal::new(backend)?;
-
-    // Setup input handling
-    let (tx, rx) = mpsc::channel();
-
-    let tick_rate = Duration::from_millis(cli.tick_rate);
-    thread::spawn(move || {
-        let mut last_tick = Instant::now();
-        loop {
-            // poll for tick rate duration, if no events, sent tick event.
-            let timeout = tick_rate
-                .checked_sub(last_tick.elapsed())
-                .unwrap_or_else(|| Duration::from_secs(0));
-            if event::poll(timeout).unwrap() {
-                if let CEvent::Key(key) = event::read().unwrap() {
-                    tx.send(Event::Input(key)).unwrap();
-                }
-            }
-            if last_tick.elapsed() >= tick_rate {
-                tx.send(Event::Tick).unwrap();
-                last_tick = Instant::now();
-            }
-        }
-    });
-
-    let mut app = App::new("Crossterm Demo", cli.enhanced_graphics);
-
-    terminal.clear()?;
-
-    loop {
-        terminal.draw(|f| ui::draw(f, &mut app))?;
-        match rx.recv()? {
-            Event::Input(event) => match event.code {
-                KeyCode::Char('q') => {
-                    disable_raw_mode()?;
-                    execute!(
-                        terminal.backend_mut(),
-                        LeaveAlternateScreen,
-                        DisableMouseCapture
-                    )?;
-                    terminal.show_cursor()?;
-                    break;
-                }
-                KeyCode::Char(c) => app.on_key(c),
-                KeyCode::Left => app.on_left(),
-                KeyCode::Up => app.on_up(),
-                KeyCode::Right => app.on_right(),
-                KeyCode::Down => app.on_down(),
-                _ => {}
-            },
-            Event::Tick => {
-                app.on_tick();
-            }
-        }
-        if app.should_quit {
-            break;
-        }
-    }
-
-    Ok(())
-}

examples/curses_demo.rs

@@ -1,74 +0,0 @@
-mod demo;
-#[allow(dead_code)]
-mod util;
-
-use crate::demo::{ui, App};
-use argh::FromArgs;
-use std::{
-    error::Error,
-    io,
-    time::{Duration, Instant},
-};
-use tui::{backend::CursesBackend, Terminal};
-
-/// Curses demo
-#[derive(Debug, FromArgs)]
-struct Cli {
-    /// time in ms between two ticks.
-    #[argh(option, default = "250")]
-    tick_rate: u64,
-    /// whether unicode symbols are used to improve the overall look of the app
-    #[argh(option, default = "true")]
-    enhanced_graphics: bool,
-}
-
-fn main() -> Result<(), Box<dyn Error>> {
-    let cli: Cli = argh::from_env();
-
-    let mut backend =
-        CursesBackend::new().ok_or_else(|| io::Error::new(io::ErrorKind::Other, ""))?;
-    let curses = backend.get_curses_mut();
-    curses.set_echo(false);
-    curses.set_input_timeout(easycurses::TimeoutMode::WaitUpTo(50));
-    curses.set_input_mode(easycurses::InputMode::RawCharacter);
-    curses.set_keypad_enabled(true);
-    let mut terminal = Terminal::new(backend)?;
-    terminal.hide_cursor()?;
-
-    let mut app = App::new("Curses demo", cli.enhanced_graphics);
-
-    let mut last_tick = Instant::now();
-    let tick_rate = Duration::from_millis(cli.tick_rate);
-    loop {
-        terminal.draw(|f| ui::draw(f, &mut app))?;
-        if let Some(input) = terminal.backend_mut().get_curses_mut().get_input() {
-            match input {
-                easycurses::Input::Character(c) => {
-                    app.on_key(c);
-                }
-                easycurses::Input::KeyUp => {
-                    app.on_up();
-                }
-                easycurses::Input::KeyDown => {
-                    app.on_down();
-                }
-                easycurses::Input::KeyLeft => {
-                    app.on_left();
-                }
-                easycurses::Input::KeyRight => {
-                    app.on_right();
-                }
-                _ => {}
-            };
-        };
-        terminal.backend_mut().get_curses_mut().flush_input();
-        if last_tick.elapsed() > tick_rate {
-            app.on_tick();
-            last_tick = Instant::now();
-        }
-        if app.should_quit {
-            break;
-        }
-    }
-    Ok(())
-}

examples/custom_widget.rs

@@ -1,23 +1,23 @@
-#[allow(dead_code)]
-mod util;
-
-use crate::util::event::{Event, Events};
+use crossterm::{
+    event::{self, DisableMouseCapture, EnableMouseCapture, Event, KeyCode},
+    execute,
+    terminal::{disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen},
+};
 use std::{error::Error, io};
-use termion::{event::Key, input::MouseTerminal, raw::IntoRawMode, screen::AlternateScreen};
 use tui::{
-    backend::TermionBackend, buffer::Buffer, layout::Rect, style::Style, widgets::Widget, Terminal,
+    backend::{Backend, CrosstermBackend},
+    buffer::Buffer,
+    layout::Rect,
+    style::Style,
+    widgets::Widget,
+    Frame, Terminal,
 };
 
+#[derive(Default)]
 struct Label<'a> {
     text: &'a str,
 }
 
-impl<'a> Default for Label<'a> {
-    fn default() -> Label<'a> {
-        Label { text: "" }
-    }
-}
-
 impl<'a> Widget for Label<'a> {
     fn render(self, area: Rect, buf: &mut Buffer) {
         buf.set_string(area.left(), area.top(), self.text, Style::default());
@@ -32,28 +32,46 @@ impl<'a> Label<'a> {
 }
 
 fn main() -> Result<(), Box<dyn Error>> {
-    // Terminal initialization
-    let stdout = io::stdout().into_raw_mode()?;
-    let stdout = MouseTerminal::from(stdout);
-    let stdout = AlternateScreen::from(stdout);
-    let backend = TermionBackend::new(stdout);
+    // setup terminal
+    enable_raw_mode()?;
+    let mut stdout = io::stdout();
+    execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
+    let backend = CrosstermBackend::new(stdout);
     let mut terminal = Terminal::new(backend)?;
 
-    let events = Events::new();
+    // create app and run it
+    let res = run_app(&mut terminal);
 
-    loop {
-        terminal.draw(|f| {
-            let size = f.size();
-            let label = Label::default().text("Test");
-            f.render_widget(label, size);
-        })?;
+    // restore terminal
+    disable_raw_mode()?;
+    execute!(
+        terminal.backend_mut(),
+        LeaveAlternateScreen,
+        DisableMouseCapture
+    )?;
+    terminal.show_cursor()?;
 
-        if let Event::Input(key) = events.next()? {
-            if key == Key::Char('q') {
-                break;
-            }
-        }
+    if let Err(err) = res {
+        println!("{:?}", err)
     }
 
     Ok(())
 }
+
+fn run_app<B: Backend>(terminal: &mut Terminal<B>) -> io::Result<()> {
+    loop {
+        terminal.draw(ui)?;
+
+        if let Event::Key(key) = event::read()? {
+            if let KeyCode::Char('q') = key.code {
+                return Ok(());
+            }
+        }
+    }
+}
+
+fn ui<B: Backend>(f: &mut Frame<B>) {
+    let size = f.size();
+    let label = Label::default().text("Test");
+    f.render_widget(label, size);
+}

examples/demo/app.rs

@@ -1,4 +1,8 @@
-use crate::util::{RandomSignal, SinSignal, StatefulList, TabsState};
+use rand::{
+    distributions::{Distribution, Uniform},
+    rngs::ThreadRng,
+};
+use tui::widgets::ListState;
 
 const TASKS: [&str; 24] = [
     "Item1", "Item2", "Item3", "Item4", "Item5", "Item6", "Item7", "Item8", "Item9", "Item10",
@@ -62,6 +66,120 @@ const EVENTS: [(&str, u64); 24] = [
     ("B24", 5),
 ];
 
+#[derive(Clone)]
+pub struct RandomSignal {
+    distribution: Uniform<u64>,
+    rng: ThreadRng,
+}
+
+impl RandomSignal {
+    pub fn new(lower: u64, upper: u64) -> RandomSignal {
+        RandomSignal {
+            distribution: Uniform::new(lower, upper),
+            rng: rand::thread_rng(),
+        }
+    }
+}
+
+impl Iterator for RandomSignal {
+    type Item = u64;
+    fn next(&mut self) -> Option<u64> {
+        Some(self.distribution.sample(&mut self.rng))
+    }
+}
+
+#[derive(Clone)]
+pub struct SinSignal {
+    x: f64,
+    interval: f64,
+    period: f64,
+    scale: f64,
+}
+
+impl SinSignal {
+    pub fn new(interval: f64, period: f64, scale: f64) -> SinSignal {
+        SinSignal {
+            x: 0.0,
+            interval,
+            period,
+            scale,
+        }
+    }
+}
+
+impl Iterator for SinSignal {
+    type Item = (f64, f64);
+    fn next(&mut self) -> Option<Self::Item> {
+        let point = (self.x, (self.x * 1.0 / self.period).sin() * self.scale);
+        self.x += self.interval;
+        Some(point)
+    }
+}
+
+pub struct TabsState<'a> {
+    pub titles: Vec<&'a str>,
+    pub index: usize,
+}
+
+impl<'a> TabsState<'a> {
+    pub fn new(titles: Vec<&'a str>) -> TabsState {
+        TabsState { titles, index: 0 }
+    }
+    pub fn next(&mut self) {
+        self.index = (self.index + 1) % self.titles.len();
+    }
+
+    pub fn previous(&mut self) {
+        if self.index > 0 {
+            self.index -= 1;
+        } else {
+            self.index = self.titles.len() - 1;
+        }
+    }
+}
+
+pub struct StatefulList<T> {
+    pub state: ListState,
+    pub items: Vec<T>,
+}
+
+impl<T> StatefulList<T> {
+    pub fn with_items(items: Vec<T>) -> StatefulList<T> {
+        StatefulList {
+            state: ListState::default(),
+            items,
+        }
+    }
+
+    pub fn next(&mut self) {
+        let i = match self.state.selected() {
+            Some(i) => {
+                if i >= self.items.len() - 1 {
+                    0
+                } else {
+                    i + 1
+                }
+            }
+            None => 0,
+        };
+        self.state.select(Some(i));
+    }
+
+    pub fn previous(&mut self) {
+        let i = match self.state.selected() {
+            Some(i) => {
+                if i == 0 {
+                    self.items.len() - 1
+                } else {
+                    i - 1
+                }
+            }
+            None => 0,
+        };
+        self.state.select(Some(i));
+    }
+}
+
 pub struct Signal<S: Iterator> {
     source: S,
     pub points: Vec<S::Item>,

examples/demo/crossterm.rs

@@ -0,0 +1,77 @@
+use crate::{app::App, ui};
+use crossterm::{
+    event::{self, DisableMouseCapture, EnableMouseCapture, Event, KeyCode},
+    execute,
+    terminal::{disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen},
+};
+use std::{
+    error::Error,
+    io,
+    time::{Duration, Instant},
+};
+use tui::{
+    backend::{Backend, CrosstermBackend},
+    Terminal,
+};
+
+pub fn run(tick_rate: Duration, enhanced_graphics: bool) -> Result<(), Box<dyn Error>> {
+    // setup terminal
+    enable_raw_mode()?;
+    let mut stdout = io::stdout();
+    execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
+    let backend = CrosstermBackend::new(stdout);
+    let mut terminal = Terminal::new(backend)?;
+
+    // create app and run it
+    let app = App::new("Crossterm Demo", enhanced_graphics);
+    let res = run_app(&mut terminal, app, tick_rate);
+
+    // restore terminal
+    disable_raw_mode()?;
+    execute!(
+        terminal.backend_mut(),
+        LeaveAlternateScreen,
+        DisableMouseCapture
+    )?;
+    terminal.show_cursor()?;
+
+    if let Err(err) = res {
+        println!("{:?}", err)
+    }
+
+    Ok(())
+}
+
+fn run_app<B: Backend>(
+    terminal: &mut Terminal<B>,
+    mut app: App,
+    tick_rate: Duration,
+) -> io::Result<()> {
+    let mut last_tick = Instant::now();
+    loop {
+        terminal.draw(|f| ui::draw(f, &mut app))?;
+
+        let timeout = tick_rate
+            .checked_sub(last_tick.elapsed())
+            .unwrap_or_else(|| Duration::from_secs(0));
+        if crossterm::event::poll(timeout)? {
+            if let Event::Key(key) = event::read()? {
+                match key.code {
+                    KeyCode::Char(c) => app.on_key(c),
+                    KeyCode::Left => app.on_left(),
+                    KeyCode::Up => app.on_up(),
+                    KeyCode::Right => app.on_right(),
+                    KeyCode::Down => app.on_down(),
+                    _ => {}
+                }
+            }
+        }
+        if last_tick.elapsed() >= tick_rate {
+            app.on_tick();
+            last_tick = Instant::now();
+        }
+        if app.should_quit {
+            return Ok(());
+        }
+    }
+}

examples/demo/main.rs

@@ -0,0 +1,31 @@
+mod app;
+#[cfg(feature = "crossterm")]
+mod crossterm;
+#[cfg(feature = "termion")]
+mod termion;
+mod ui;
+
+#[cfg(feature = "crossterm")]
+use crate::crossterm::run;
+#[cfg(feature = "termion")]
+use crate::termion::run;
+use argh::FromArgs;
+use std::{error::Error, time::Duration};
+
+/// Demo
+#[derive(Debug, FromArgs)]
+struct Cli {
+    /// time in ms between two ticks.
+    #[argh(option, default = "250")]
+    tick_rate: u64,
+    /// whether unicode symbols are used to improve the overall look of the app
+    #[argh(option, default = "true")]
+    enhanced_graphics: bool,
+}
+
+fn main() -> Result<(), Box<dyn Error>> {
+    let cli: Cli = argh::from_env();
+    let tick_rate = Duration::from_millis(cli.tick_rate);
+    run(tick_rate, cli.enhanced_graphics)?;
+    Ok(())
+}

examples/demo/mod.rs

@@ -1,3 +0,0 @@
-mod app;
-pub mod ui;
-pub use app::App;

examples/demo/termion.rs

@@ -0,0 +1,80 @@
+use crate::{app::App, ui};
+use std::{error::Error, io, sync::mpsc, thread, time::Duration};
+use termion::{
+    event::Key,
+    input::{MouseTerminal, TermRead},
+    raw::IntoRawMode,
+    screen::AlternateScreen,
+};
+use tui::{
+    backend::{Backend, TermionBackend},
+    Terminal,
+};
+
+pub fn run(tick_rate: Duration, enhanced_graphics: bool) -> Result<(), Box<dyn Error>> {
+    // setup terminal
+    let stdout = io::stdout().into_raw_mode()?;
+    let stdout = MouseTerminal::from(stdout);
+    let stdout = AlternateScreen::from(stdout);
+    let backend = TermionBackend::new(stdout);
+    let mut terminal = Terminal::new(backend)?;
+
+    // create app and run it
+    let app = App::new("Termion demo", enhanced_graphics);
+    run_app(&mut terminal, app, tick_rate)?;
+
+    Ok(())
+}
+
+fn run_app<B: Backend>(
+    terminal: &mut Terminal<B>,
+    mut app: App,
+    tick_rate: Duration,
+) -> Result<(), Box<dyn Error>> {
+    let events = events(tick_rate);
+    loop {
+        terminal.draw(|f| ui::draw(f, &mut app))?;
+
+        match events.recv()? {
+            Event::Input(key) => match key {
+                Key::Char(c) => app.on_key(c),
+                Key::Up => app.on_up(),
+                Key::Down => app.on_down(),
+                Key::Left => app.on_left(),
+                Key::Right => app.on_right(),
+                _ => {}
+            },
+            Event::Tick => app.on_tick(),
+        }
+        if app.should_quit {
+            return Ok(());
+        }
+    }
+}
+
+enum Event {
+    Input(Key),
+    Tick,
+}
+
+fn events(tick_rate: Duration) -> mpsc::Receiver<Event> {
+    let (tx, rx) = mpsc::channel();
+    let keys_tx = tx.clone();
+    thread::spawn(move || {
+        let stdin = io::stdin();
+        for key in stdin.keys().flatten() {
+            if let Err(err) = keys_tx.send(Event::Input(key)) {
+                eprintln!("{}", err);
+                return;
+            }
+        }
+    });
+    thread::spawn(move || loop {
+        if let Err(err) = tx.send(Event::Tick) {
+            eprintln!("{}", err);
+            break;
+        }
+        thread::sleep(tick_rate);
+    });
+    rx
+}

examples/demo/ui.rs

@@ -1,4 +1,4 @@
-use crate::demo::App;
+use crate::app::App;
 use tui::{
     backend::Backend,
     layout::{Constraint, Direction, Layout, Rect},
@@ -363,7 +363,11 @@ where
                 } else {
                     Color::Red
                 };
-                ctx.print(server.coords.1, server.coords.0, "X", color);
+                ctx.print(
+                    server.coords.1,
+                    server.coords.0,
+                    Span::styled("X", Style::default().fg(color)),
+                );
             }
         })
         .marker(if app.enhanced_graphics {

examples/gauge.rs

@@ -1,16 +1,20 @@
-#[allow(dead_code)]
-mod util;
-
-use crate::util::event::{Config, Event, Events};
-use std::{error::Error, io, time::Duration};
-use termion::{event::Key, input::MouseTerminal, raw::IntoRawMode, screen::AlternateScreen};
+use crossterm::{
+    event::{self, DisableMouseCapture, EnableMouseCapture, Event, KeyCode},
+    execute,
+    terminal::{disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen},
+};
+use std::{
+    error::Error,
+    io,
+    time::{Duration, Instant},
+};
 use tui::{
-    backend::TermionBackend,
+    backend::{Backend, CrosstermBackend},
     layout::{Constraint, Direction, Layout},
     style::{Color, Modifier, Style},
     text::Span,
     widgets::{Block, Borders, Gauge},
-    Terminal,
+    Frame, Terminal,
 };
 
 struct App {
@@ -30,7 +34,7 @@ impl App {
         }
     }
 
-    fn update(&mut self) {
+    fn on_tick(&mut self) {
         self.progress1 += 1;
         if self.progress1 > 100 {
             self.progress1 = 0;
@@ -51,87 +55,112 @@ impl App {
 }
 
 fn main() -> Result<(), Box<dyn Error>> {
-    // Terminal initialization
-    let stdout = io::stdout().into_raw_mode()?;
-    let stdout = MouseTerminal::from(stdout);
-    let stdout = AlternateScreen::from(stdout);
-    let backend = TermionBackend::new(stdout);
+    // setup terminal
+    enable_raw_mode()?;
+    let mut stdout = io::stdout();
+    execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
+    let backend = CrosstermBackend::new(stdout);
     let mut terminal = Terminal::new(backend)?;
 
-    let events = Events::with_config(Config {
-        tick_rate: Duration::from_millis(100),
-    });
+    // create app and run it
+    let tick_rate = Duration::from_millis(250);
+    let app = App::new();
+    let res = run_app(&mut terminal, app, tick_rate);
 
-    let mut app = App::new();
+    // restore terminal
+    disable_raw_mode()?;
+    execute!(
+        terminal.backend_mut(),
+        LeaveAlternateScreen,
+        DisableMouseCapture
+    )?;
+    terminal.show_cursor()?;
 
-    loop {
-        terminal.draw(|f| {
-            let chunks = Layout::default()
-                .direction(Direction::Vertical)
-                .margin(2)
-                .constraints(
-                    [
-                        Constraint::Percentage(25),
-                        Constraint::Percentage(25),
-                        Constraint::Percentage(25),
-                        Constraint::Percentage(25),
-                    ]
-                    .as_ref(),
-                )
-                .split(f.size());
-
-            let gauge = Gauge::default()
-                .block(Block::default().title("Gauge1").borders(Borders::ALL))
-                .gauge_style(Style::default().fg(Color::Yellow))
-                .percent(app.progress1);
-            f.render_widget(gauge, chunks[0]);
-
-            let label = format!("{}/100", app.progress2);
-            let gauge = Gauge::default()
-                .block(Block::default().title("Gauge2").borders(Borders::ALL))
-                .gauge_style(Style::default().fg(Color::Magenta).bg(Color::Green))
-                .percent(app.progress2)
-                .label(label);
-            f.render_widget(gauge, chunks[1]);
-
-            let label = Span::styled(
-                format!("{:.2}%", app.progress3 * 100.0),
-                Style::default()
-                    .fg(Color::Red)
-                    .add_modifier(Modifier::ITALIC | Modifier::BOLD),
-            );
-            let gauge = Gauge::default()
-                .block(Block::default().title("Gauge3").borders(Borders::ALL))
-                .gauge_style(Style::default().fg(Color::Yellow))
-                .ratio(app.progress3)
-                .label(label)
-                .use_unicode(true);
-            f.render_widget(gauge, chunks[2]);
-
-            let label = format!("{}/100", app.progress2);
-            let gauge = Gauge::default()
-                .block(Block::default().title("Gauge4"))
-                .gauge_style(
-                    Style::default()
-                        .fg(Color::Cyan)
-                        .add_modifier(Modifier::ITALIC),
-                )
-                .percent(app.progress4)
-                .label(label);
-            f.render_widget(gauge, chunks[3]);
-        })?;
-
-        match events.next()? {
-            Event::Input(input) => {
-                if input == Key::Char('q') {
-                    break;
-                }
-            }
-            Event::Tick => {
-                app.update();
-            }
-        }
+    if let Err(err) = res {
+        println!("{:?}", err)
     }
 
     Ok(())
 }
+
+fn run_app<B: Backend>(
+    terminal: &mut Terminal<B>,
+    mut app: App,
+    tick_rate: Duration,
+) -> io::Result<()> {
+    let mut last_tick = Instant::now();
+    loop {
+        terminal.draw(|f| ui(f, &app))?;
+
+        let timeout = tick_rate
+            .checked_sub(last_tick.elapsed())
+            .unwrap_or_else(|| Duration::from_secs(0));
+        if crossterm::event::poll(timeout)? {
+            if let Event::Key(key) = event::read()? {
+                if let KeyCode::Char('q') = key.code {
+                    return Ok(());
+                }
+            }
+        }
+        if last_tick.elapsed() >= tick_rate {
+            app.on_tick();
+            last_tick = Instant::now();
+        }
+    }
+}
+
+fn ui<B: Backend>(f: &mut Frame<B>, app: &App) {
+    let chunks = Layout::default()
+        .direction(Direction::Vertical)
+        .margin(2)
+        .constraints(
+            [
+                Constraint::Percentage(25),
+                Constraint::Percentage(25),
+                Constraint::Percentage(25),
+                Constraint::Percentage(25),
+            ]
+            .as_ref(),
+        )
+        .split(f.size());
+
+    let gauge = Gauge::default()
+        .block(Block::default().title("Gauge1").borders(Borders::ALL))
+        .gauge_style(Style::default().fg(Color::Yellow))
+        .percent(app.progress1);
+    f.render_widget(gauge, chunks[0]);
+
+    let label = format!("{}/100", app.progress2);
+    let gauge = Gauge::default()
+        .block(Block::default().title("Gauge2").borders(Borders::ALL))
+        .gauge_style(Style::default().fg(Color::Magenta).bg(Color::Green))
+        .percent(app.progress2)
+        .label(label);
+    f.render_widget(gauge, chunks[1]);
+
+    let label = Span::styled(
+        format!("{:.2}%", app.progress3 * 100.0),
+        Style::default()
+            .fg(Color::Red)
+            .add_modifier(Modifier::ITALIC | Modifier::BOLD),
+    );
+    let gauge = Gauge::default()
+        .block(Block::default().title("Gauge3").borders(Borders::ALL))
+        .gauge_style(Style::default().fg(Color::Yellow))
+        .ratio(app.progress3)
+        .label(label)
+        .use_unicode(true);
+    f.render_widget(gauge, chunks[2]);
+
+    let label = format!("{}/100", app.progress2);
+    let gauge = Gauge::default()
+        .block(Block::default().title("Gauge4"))
+        .gauge_style(
+            Style::default()
+                .fg(Color::Cyan)
+                .add_modifier(Modifier::ITALIC),
+        )
+        .percent(app.progress4)
+        .label(label);
+    f.render_widget(gauge, chunks[3]);
+}

examples/inline.rs

@@ -0,0 +1,311 @@
+use rand::distributions::{Distribution, Uniform};
+use std::{
+    collections::{BTreeMap, VecDeque},
+    error::Error,
+    io,
+    sync::mpsc,
+    thread,
+    time::{Duration, Instant},
+};
+use tracing::{event, span, Level};
+use tui::{
+    backend::{Backend, CrosstermBackend},
+    layout::{Alignment, Constraint, Direction, Layout, Rect},
+    style::{Color, Modifier, Style},
+    symbols,
+    text::{Span, Spans},
+    widgets::{Block, Gauge, LineGauge, List, ListItem, Paragraph, Widget},
+    Frame, Terminal, TerminalOptions, ViewportVariant,
+};
+
+const NUM_DOWNLOADS: usize = 10;
+
+type DownloadId = usize;
+type WorkerId = usize;
+
+enum Event {
+    Input(crossterm::event::KeyEvent),
+    Tick,
+    Resize,
+    DownloadUpdate(WorkerId, DownloadId, f64),
+    DownloadDone(WorkerId, DownloadId),
+}
+
+struct Downloads {
+    pending: VecDeque<Download>,
+    in_progress: BTreeMap<WorkerId, DownloadInProgress>,
+}
+
+impl Downloads {
+    fn next(&mut self, worker_id: WorkerId) -> Option<Download> {
+        match self.pending.pop_front() {
+            Some(d) => {
+                self.in_progress.insert(
+                    worker_id,
+                    DownloadInProgress {
+                        id: d.id,
+                        started_at: Instant::now(),
+                        progress: 0.0,
+                    },
+                );
+                Some(d)
+            }
+            None => None,
+        }
+    }
+}
+
+struct DownloadInProgress {
+    id: DownloadId,
+    started_at: Instant,
+    progress: f64,
+}
+
+struct Download {
+    id: DownloadId,
+    size: usize,
+}
+
+struct Worker {
+    id: WorkerId,
+    tx: mpsc::Sender<Download>,
+}
+
+fn main() -> Result<(), Box<dyn Error>> {
+    tracing_subscriber::fmt()
+        .with_env_filter(tracing_subscriber::EnvFilter::from_default_env())
+        .with_writer(io::stderr)
+        .init();
+
+    crossterm::terminal::enable_raw_mode()?;
+    let stdout = io::stdout();
+    let backend = CrosstermBackend::new(stdout);
+    let mut terminal = Terminal::with_options(
+        backend,
+        TerminalOptions {
+            viewport: ViewportVariant::Inline(8),
+        },
+    )?;
+
+    let (tx, rx) = mpsc::channel();
+    input_handling(tx.clone());
+    let workers = workers(tx);
+    let mut downloads = downloads();
+
+    for w in &workers {
+        let d = downloads.next(w.id).unwrap();
+        w.tx.send(d).unwrap();
+    }
+
+    run_app(&mut terminal, workers, downloads, rx)?;
+
+    crossterm::terminal::disable_raw_mode()?;
+    terminal.clear()?;
+
+    Ok(())
+}
+
+fn input_handling(tx: mpsc::Sender<Event>) {
+    let tick_rate = Duration::from_millis(200);
+    thread::spawn(move || {
+        let mut last_tick = Instant::now();
+        loop {
+            // poll for tick rate duration, if no events, sent tick event.
+            let timeout = tick_rate
+                .checked_sub(last_tick.elapsed())
+                .unwrap_or_else(|| Duration::from_secs(0));
+            if crossterm::event::poll(timeout).unwrap() {
+                match crossterm::event::read().unwrap() {
+                    crossterm::event::Event::Key(key) => tx.send(Event::Input(key)).unwrap(),
+                    crossterm::event::Event::Resize(_, _) => tx.send(Event::Resize).unwrap(),
+                    _ => {}
+                };
+            }
+            if last_tick.elapsed() >= tick_rate {
+                tx.send(Event::Tick).unwrap();
+                last_tick = Instant::now();
+            }
+        }
+    });
+}
+
+fn workers(tx: mpsc::Sender<Event>) -> Vec<Worker> {
+    (0..4)
+        .map(|id| {
+            let (worker_tx, worker_rx) = mpsc::channel::<Download>();
+            let tx = tx.clone();
+            thread::spawn(move || {
+                while let Ok(download) = worker_rx.recv() {
+                    let mut remaining = download.size;
+                    while remaining > 0 {
+                        let wait = (remaining as u64).min(10);
+                        thread::sleep(Duration::from_millis(wait * 10));
+                        remaining = remaining.saturating_sub(10);
+                        let progress = (download.size - remaining) * 100 / download.size;
+                        tx.send(Event::DownloadUpdate(id, download.id, progress as f64))
+                            .unwrap();
+                    }
+                    tx.send(Event::DownloadDone(id, download.id)).unwrap();
+                }
+            });
+            Worker { id, tx: worker_tx }
+        })
+        .collect()
+}
+
+fn downloads() -> Downloads {
+    let distribution = Uniform::new(0, 1000);
+    let mut rng = rand::thread_rng();
+    let pending = (0..NUM_DOWNLOADS)
+        .map(|id| {
+            let size = distribution.sample(&mut rng);
+            Download { id, size }
+        })
+        .collect();
+    Downloads {
+        pending,
+        in_progress: BTreeMap::new(),
+    }
+}
+
+fn run_app<B: Backend>(
+    terminal: &mut Terminal<B>,
+    workers: Vec<Worker>,
+    mut downloads: Downloads,
+    rx: mpsc::Receiver<Event>,
+) -> Result<(), Box<dyn Error>> {
+    let mut redraw = true;
+    loop {
+        if redraw {
+            terminal.draw(|f| ui(f, &downloads))?;
+        }
+        redraw = true;
+
+        let span = span!(Level::INFO, "recv");
+        let _guard = span.enter();
+        match rx.recv()? {
+            Event::Input(event) => {
+                if event.code == crossterm::event::KeyCode::Char('q') {
+                    break;
+                }
+            }
+            Event::Resize => {
+                event!(Level::INFO, "resize");
+                terminal.resize()?;
+            }
+            Event::Tick => {
+                event!(Level::INFO, "tick");
+            }
+            Event::DownloadUpdate(worker_id, download_id, progress) => {
+                event!(
+                    Level::INFO,
+                    worker_id,
+                    download_id,
+                    progress,
+                    "download update"
+                );
+                let download = downloads.in_progress.get_mut(&worker_id).unwrap();
+                download.progress = progress;
+                redraw = false
+            }
+            Event::DownloadDone(worker_id, download_id) => {
+                event!(Level::INFO, worker_id, download_id, "download done");
+                let download = downloads.in_progress.remove(&worker_id).unwrap();
+                terminal.insert_before(1, |buf| {
+                    Paragraph::new(Spans::from(vec![
+                        Span::from("Finished "),
+                        Span::styled(
+                            format!("download {}", download_id),
+                            Style::default().add_modifier(Modifier::BOLD),
+                        ),
+                        Span::from(format!(
+                            " in {}ms",
+                            download.started_at.elapsed().as_millis()
+                        )),
+                    ]))
+                    .render(buf.area, buf);
+                })?;
+                match downloads.next(worker_id) {
+                    Some(d) => workers[worker_id].tx.send(d).unwrap(),
+                    None => {
+                        if downloads.in_progress.is_empty() {
+                            terminal.insert_before(1, |buf| {
+                                Paragraph::new("Done !").render(buf.area, buf);
+                            })?;
+                            break;
+                        }
+                    }
+                };
+            }
+        };
+    }
+    Ok(())
+}
+
+fn ui<B: Backend>(f: &mut Frame<B>, downloads: &Downloads) {
+    let size = f.size();
+
+    let block = Block::default()
+        .title("Progress")
+        .title_alignment(Alignment::Center);
+    f.render_widget(block, size);
+
+    let chunks = Layout::default()
+        .constraints(vec![Constraint::Length(2), Constraint::Length(4)])
+        .margin(1)
+        .split(size);
+
+    // total progress
+    let done = NUM_DOWNLOADS - downloads.pending.len() - downloads.in_progress.len();
+    let progress = LineGauge::default()
+        .gauge_style(Style::default().fg(Color::Blue))
+        .label(format!("{}/{}", done, NUM_DOWNLOADS))
+        .ratio(done as f64 / NUM_DOWNLOADS as f64);
+    f.render_widget(progress, chunks[0]);
+
+    let chunks = Layout::default()
+        .direction(Direction::Horizontal)
+        .constraints(vec![Constraint::Percentage(20), Constraint::Percentage(80)])
+        .split(chunks[1]);
+
+    // in progress downloads
+    let items: Vec<ListItem> = downloads
+        .in_progress
+        .iter()
+        .map(|(_worker_id, download)| {
+            ListItem::new(Spans::from(vec![
+                Span::raw(symbols::DOT),
+                Span::styled(
+                    format!(" download {:>2}", download.id),
+                    Style::default()
+                        .fg(Color::LightGreen)
+                        .add_modifier(Modifier::BOLD),
+                ),
+                Span::raw(format!(
+                    " ({}ms)",
+                    download.started_at.elapsed().as_millis()
+                )),
+            ]))
+        })
+        .collect();
+    let list = List::new(items);
+    f.render_widget(list, chunks[0]);
+
+    for (i, (_, download)) in downloads.in_progress.iter().enumerate() {
+        let gauge = Gauge::default()
+            .gauge_style(Style::default().fg(Color::Yellow))
+            .ratio(download.progress / 100.0);
+        if chunks[1].top().saturating_add(i as u16) > size.bottom() {
+            continue;
+        }
+        f.render_widget(
+            gauge,
+            Rect {
+                x: chunks[1].left(),
+                y: chunks[1].top().saturating_add(i as u16),
+                width: chunks[1].width,
+                height: 1,
+            },
+        );
+    }
+}

examples/layout.rs

@@ -1,52 +1,70 @@
-#[allow(dead_code)]
-mod util;
-
-use crate::util::event::{Event, Events};
+use crossterm::{
+    event::{self, DisableMouseCapture, EnableMouseCapture, Event, KeyCode},
+    execute,
+    terminal::{disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen},
+};
 use std::{error::Error, io};
-use termion::{event::Key, input::MouseTerminal, raw::IntoRawMode, screen::AlternateScreen};
 use tui::{
-    backend::TermionBackend,
+    backend::{Backend, CrosstermBackend},
     layout::{Constraint, Direction, Layout},
     widgets::{Block, Borders},
-    Terminal,
+    Frame, Terminal,
 };
 
 fn main() -> Result<(), Box<dyn Error>> {
-    // Terminal initialization
-    let stdout = io::stdout().into_raw_mode()?;
-    let stdout = MouseTerminal::from(stdout);
-    let stdout = AlternateScreen::from(stdout);
-    let backend = TermionBackend::new(stdout);
+    // setup terminal
+    enable_raw_mode()?;
+    let mut stdout = io::stdout();
+    execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
+    let backend = CrosstermBackend::new(stdout);
     let mut terminal = Terminal::new(backend)?;
 
-    let events = Events::new();
+    // create app and run it
+    let res = run_app(&mut terminal);
 
-    loop {
-        terminal.draw(|f| {
-            let chunks = Layout::default()
-                .direction(Direction::Vertical)
-                .constraints(
-                    [
-                        Constraint::Percentage(10),
-                        Constraint::Percentage(80),
-                        Constraint::Percentage(10),
-                    ]
-                    .as_ref(),
-                )
-                .split(f.size());
+    // restore terminal
+    disable_raw_mode()?;
+    execute!(
+        terminal.backend_mut(),
+        LeaveAlternateScreen,
+        DisableMouseCapture
+    )?;
+    terminal.show_cursor()?;
 
-            let block = Block::default().title("Block").borders(Borders::ALL);
-            f.render_widget(block, chunks[0]);
-            let block = Block::default().title("Block 2").borders(Borders::ALL);
-            f.render_widget(block, chunks[2]);
-        })?;
-
-        if let Event::Input(input) = events.next()? {
-            if let Key::Char('q') = input {
-                break;
-            }
-        }
+    if let Err(err) = res {
+        println!("{:?}", err)
     }
 
     Ok(())
 }
+
+fn run_app<B: Backend>(terminal: &mut Terminal<B>) -> io::Result<()> {
+    loop {
+        terminal.draw(|f| ui(f))?;
+
+        if let Event::Key(key) = event::read()? {
+            if let KeyCode::Char('q') = key.code {
+                return Ok(());
+            }
+        }
+    }
+}
+
+fn ui<B: Backend>(f: &mut Frame<B>) {
+    let chunks = Layout::default()
+        .direction(Direction::Vertical)
+        .constraints(
+            [
+                Constraint::Percentage(10),
+                Constraint::Percentage(80),
+                Constraint::Percentage(10),
+            ]
+            .as_ref(),
+        )
+        .split(f.size());
+
+    let block = Block::default().title("Block").borders(Borders::ALL);
+    f.render_widget(block, chunks[0]);
+    let block = Block::default().title("Block 2").borders(Borders::ALL);
+    f.render_widget(block, chunks[2]);
+}

examples/list.rs

@@ -1,21 +1,68 @@
-#[allow(dead_code)]
-mod util;
-
-use crate::util::{
-    event::{Event, Events},
-    StatefulList,
+use crossterm::{
+    event::{self, DisableMouseCapture, EnableMouseCapture, Event, KeyCode},
+    execute,
+    terminal::{disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen},
+};
+use std::{
+    error::Error,
+    io,
+    time::{Duration, Instant},
 };
-use std::{error::Error, io};
-use termion::{event::Key, input::MouseTerminal, raw::IntoRawMode, screen::AlternateScreen};
 use tui::{
-    backend::TermionBackend,
+    backend::{Backend, CrosstermBackend},
     layout::{Constraint, Corner, Direction, Layout},
     style::{Color, Modifier, Style},
     text::{Span, Spans},
-    widgets::{Block, Borders, List, ListItem},
-    Terminal,
+    widgets::{Block, Borders, List, ListItem, ListState},
+    Frame, Terminal,
 };
 
+struct StatefulList<T> {
+    state: ListState,
+    items: Vec<T>,
+}
+
+impl<T> StatefulList<T> {
+    fn with_items(items: Vec<T>) -> StatefulList<T> {
+        StatefulList {
+            state: ListState::default(),
+            items,
+        }
+    }
+
+    fn next(&mut self) {
+        let i = match self.state.selected() {
+            Some(i) => {
+                if i >= self.items.len() - 1 {
+                    0
+                } else {
+                    i + 1
+                }
+            }
+            None => 0,
+        };
+        self.state.select(Some(i));
+    }
+
+    fn previous(&mut self) {
+        let i = match self.state.selected() {
+            Some(i) => {
+                if i == 0 {
+                    self.items.len() - 1
+                } else {
+                    i - 1
+                }
+            }
+            None => 0,
+        };
+        self.state.select(Some(i));
+    }
+
+    fn unselect(&mut self) {
+        self.state.select(None);
+    }
+}
+
 /// This struct holds the current state of the app. In particular, it has the `items` field which is a wrapper
 /// around `ListState`. Keeping track of the items state let us render the associated widget with its state
 /// and have access to features such as natural scrolling.
@@ -90,134 +137,150 @@ impl<'a> App<'a> {
 
     /// Rotate through the event list.
     /// This only exists to simulate some kind of "progress"
-    fn advance(&mut self) {
+    fn on_tick(&mut self) {
         let event = self.events.remove(0);
         self.events.push(event);
     }
 }
 
 fn main() -> Result<(), Box<dyn Error>> {
-    // Terminal initialization
-    let stdout = io::stdout().into_raw_mode()?;
-    let stdout = MouseTerminal::from(stdout);
-    let stdout = AlternateScreen::from(stdout);
-    let backend = TermionBackend::new(stdout);
+    // setup terminal
+    enable_raw_mode()?;
+    let mut stdout = io::stdout();
+    execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
+    let backend = CrosstermBackend::new(stdout);
     let mut terminal = Terminal::new(backend)?;
 
-    let events = Events::new();
+    // create app and run it
+    let tick_rate = Duration::from_millis(250);
+    let app = App::new();
+    let res = run_app(&mut terminal, app, tick_rate);
 
-    // Create a new app with some example state
-    let mut app = App::new();
+    // restore terminal
+    disable_raw_mode()?;
+    execute!(
+        terminal.backend_mut(),
+        LeaveAlternateScreen,
+        DisableMouseCapture
+    )?;
+    terminal.show_cursor()?;
 
-    loop {
-        terminal.draw(|f| {
-            // Create two chunks with equal horizontal screen space
-            let chunks = Layout::default()
-                .direction(Direction::Horizontal)
-                .constraints([Constraint::Percentage(50), Constraint::Percentage(50)].as_ref())
-                .split(f.size());
-
-            // Iterate through all elements in the `items` app and append some debug text to it.
-            let items: Vec<ListItem> = app
-                .items
-                .items
-                .iter()
-                .map(|i| {
-                    let mut lines = vec![Spans::from(i.0)];
-                    for _ in 0..i.1 {
-                        lines.push(Spans::from(Span::styled(
-                            "Lorem ipsum dolor sit amet, consectetur adipiscing elit.",
-                            Style::default().add_modifier(Modifier::ITALIC),
-                        )));
-                    }
-                    ListItem::new(lines).style(Style::default().fg(Color::Black).bg(Color::White))
-                })
-                .collect();
-
-            // Create a List from all list items and highlight the currently selected one
-            let items = List::new(items)
-                .block(Block::default().borders(Borders::ALL).title("List"))
-                .highlight_style(
-                    Style::default()
-                        .bg(Color::LightGreen)
-                        .add_modifier(Modifier::BOLD),
-                )
-                .highlight_symbol(">> ");
-
-            // We can now render the item list
-            f.render_stateful_widget(items, chunks[0], &mut app.items.state);
-
-            // Let's do the same for the events.
-            // The event list doesn't have any state and only displays the current state of the list.
-            let events: Vec<ListItem> = app
-                .events
-                .iter()
-                .rev()
-                .map(|&(event, level)| {
-                    // Colorcode the level depending on its type
-                    let s = match level {
-                        "CRITICAL" => Style::default().fg(Color::Red),
-                        "ERROR" => Style::default().fg(Color::Magenta),
-                        "WARNING" => Style::default().fg(Color::Yellow),
-                        "INFO" => Style::default().fg(Color::Blue),
-                        _ => Style::default(),
-                    };
-                    // Add a example datetime and apply proper spacing between them
-                    let header = Spans::from(vec![
-                        Span::styled(format!("{:<9}", level), s),
-                        Span::raw(" "),
-                        Span::styled(
-                            "2020-01-01 10:00:00",
-                            Style::default().add_modifier(Modifier::ITALIC),
-                        ),
-                    ]);
-                    // The event gets its own line
-                    let log = Spans::from(vec![Span::raw(event)]);
-
-                    // Here several things happen:
-                    // 1. Add a `---` spacing line above the final list entry
-                    // 2. Add the Level + datetime
-                    // 3. Add a spacer line
-                    // 4. Add the actual event
-                    ListItem::new(vec![
-                        Spans::from("-".repeat(chunks[1].width as usize)),
-                        header,
-                        Spans::from(""),
-                        log,
-                    ])
-                })
-                .collect();
-            let events_list = List::new(events)
-                .block(Block::default().borders(Borders::ALL).title("List"))
-                .start_corner(Corner::BottomLeft);
-            f.render_widget(events_list, chunks[1]);
-        })?;
-
-        // This is a simple example on how to handle events
-        // 1. This breaks the loop and exits the program on `q` button press.
-        // 2. The `up`/`down` keys change the currently selected item in the App's `items` list.
-        // 3. `left` unselects the current item.
-        match events.next()? {
-            Event::Input(input) => match input {
-                Key::Char('q') => {
-                    break;
-                }
-                Key::Left => {
-                    app.items.unselect();
-                }
-                Key::Down => {
-                    app.items.next();
-                }
-                Key::Up => {
-                    app.items.previous();
-                }
-                _ => {}
-            },
-            Event::Tick => {
-                app.advance();
-            }
-        }
+    if let Err(err) = res {
+        println!("{:?}", err)
     }
 
     Ok(())
 }
+
+fn run_app<B: Backend>(
+    terminal: &mut Terminal<B>,
+    mut app: App,
+    tick_rate: Duration,
+) -> io::Result<()> {
+    let mut last_tick = Instant::now();
+    loop {
+        terminal.draw(|f| ui(f, &mut app))?;
+
+        let timeout = tick_rate
+            .checked_sub(last_tick.elapsed())
+            .unwrap_or_else(|| Duration::from_secs(0));
+        if crossterm::event::poll(timeout)? {
+            if let Event::Key(key) = event::read()? {
+                match key.code {
+                    KeyCode::Char('q') => return Ok(()),
+                    KeyCode::Left => app.items.unselect(),
+                    KeyCode::Down => app.items.next(),
+                    KeyCode::Up => app.items.previous(),
+                    _ => {}
+                }
+            }
+        }
+        if last_tick.elapsed() >= tick_rate {
+            app.on_tick();
+            last_tick = Instant::now();
+        }
+    }
+}
+
+fn ui<B: Backend>(f: &mut Frame<B>, app: &mut App) {
+    // Create two chunks with equal horizontal screen space
+    let chunks = Layout::default()
+        .direction(Direction::Horizontal)
+        .constraints([Constraint::Percentage(50), Constraint::Percentage(50)].as_ref())
+        .split(f.size());
+
+    // Iterate through all elements in the `items` app and append some debug text to it.
+    let items: Vec<ListItem> = app
+        .items
+        .items
+        .iter()
+        .map(|i| {
+            let mut lines = vec![Spans::from(i.0)];
+            for _ in 0..i.1 {
+                lines.push(Spans::from(Span::styled(
+                    "Lorem ipsum dolor sit amet, consectetur adipiscing elit.",
+                    Style::default().add_modifier(Modifier::ITALIC),
+                )));
+            }
+            ListItem::new(lines).style(Style::default().fg(Color::Black).bg(Color::White))
+        })
+        .collect();
+
+    // Create a List from all list items and highlight the currently selected one
+    let items = List::new(items)
+        .block(Block::default().borders(Borders::ALL).title("List"))
+        .highlight_style(
+            Style::default()
+                .bg(Color::LightGreen)
+                .add_modifier(Modifier::BOLD),
+        )
+        .highlight_symbol(">> ");
+
+    // We can now render the item list
+    f.render_stateful_widget(items, chunks[0], &mut app.items.state);
+
+    // Let's do the same for the events.
+    // The event list doesn't have any state and only displays the current state of the list.
+    let events: Vec<ListItem> = app
+        .events
+        .iter()
+        .rev()
+        .map(|&(event, level)| {
+            // Colorcode the level depending on its type
+            let s = match level {
+                "CRITICAL" => Style::default().fg(Color::Red),
+                "ERROR" => Style::default().fg(Color::Magenta),
+                "WARNING" => Style::default().fg(Color::Yellow),
+                "INFO" => Style::default().fg(Color::Blue),
+                _ => Style::default(),
+            };
+            // Add a example datetime and apply proper spacing between them
+            let header = Spans::from(vec![
+                Span::styled(format!("{:<9}", level), s),
+                Span::raw(" "),
+                Span::styled(
+                    "2020-01-01 10:00:00",
+                    Style::default().add_modifier(Modifier::ITALIC),
+                ),
+            ]);
+            // The event gets its own line
+            let log = Spans::from(vec![Span::raw(event)]);
+
+            // Here several things happen:
+            // 1. Add a `---` spacing line above the final list entry
+            // 2. Add the Level + datetime
+            // 3. Add a spacer line
+            // 4. Add the actual event
+            ListItem::new(vec![
+                Spans::from("-".repeat(chunks[1].width as usize)),
+                header,
+                Spans::from(""),
+                log,
+            ])
+        })
+        .collect();
+    let events_list = List::new(events)
+        .block(Block::default().borders(Borders::ALL).title("List"))
+        .start_corner(Corner::BottomLeft);
+    f.render_widget(events_list, chunks[1]);
+}

examples/paragraph.rs

@@ -1,111 +1,171 @@
-#[allow(dead_code)]
-mod util;
-
-use crate::util::event::{Event, Events};
-use std::{error::Error, io};
-use termion::{event::Key, input::MouseTerminal, raw::IntoRawMode, screen::AlternateScreen};
+use crossterm::{
+    event::{self, DisableMouseCapture, EnableMouseCapture, Event, KeyCode},
+    execute,
+    terminal::{disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen},
+};
+use std::{
+    error::Error,
+    io,
+    time::{Duration, Instant},
+};
 use tui::{
-    backend::TermionBackend,
+    backend::{Backend, CrosstermBackend},
     layout::{Alignment, Constraint, Direction, Layout},
     style::{Color, Modifier, Style},
     text::{Span, Spans},
     widgets::{Block, Borders, Paragraph, Wrap},
-    Terminal,
+    Frame, Terminal,
 };
 
+struct App {
+    scroll: u16,
+}
+
+impl App {
+    fn new() -> App {
+        App { scroll: 0 }
+    }
+
+    fn on_tick(&mut self) {
+        self.scroll += 1;
+        self.scroll %= 10;
+    }
+}
+
 fn main() -> Result<(), Box<dyn Error>> {
-    // Terminal initialization
-    let stdout = io::stdout().into_raw_mode()?;
-    let stdout = MouseTerminal::from(stdout);
-    let stdout = AlternateScreen::from(stdout);
-    let backend = TermionBackend::new(stdout);
+    // setup terminal
+    enable_raw_mode()?;
+    let mut stdout = io::stdout();
+    execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
+    let backend = CrosstermBackend::new(stdout);
     let mut terminal = Terminal::new(backend)?;
 
-    let events = Events::new();
+    // create app and run it
+    let tick_rate = Duration::from_millis(250);
+    let app = App::new();
+    let res = run_app(&mut terminal, app, tick_rate);
 
-    let mut scroll: u16 = 0;
-    loop {
-        terminal.draw(|f| {
-            let size = f.size();
+    // restore terminal
+    disable_raw_mode()?;
+    execute!(
+        terminal.backend_mut(),
+        LeaveAlternateScreen,
+        DisableMouseCapture
+    )?;
+    terminal.show_cursor()?;
 
-            // Words made "loooong" to demonstrate line breaking.
-            let s = "Veeeeeeeeeeeeeeeery    loooooooooooooooooong   striiiiiiiiiiiiiiiiiiiiiiiiiing.   ";
-            let mut long_line = s.repeat(usize::from(size.width) / s.len() + 4);
-            long_line.push('\n');
-
-            let block = Block::default()
-                .style(Style::default().bg(Color::White).fg(Color::Black));
-            f.render_widget(block, size);
-
-            let chunks = Layout::default()
-                .direction(Direction::Vertical)
-                .margin(5)
-                .constraints(
-                    [
-                        Constraint::Percentage(25),
-                        Constraint::Percentage(25),
-                        Constraint::Percentage(25),
-                        Constraint::Percentage(25),
-                    ]
-                    .as_ref(),
-                )
-                .split(size);
-
-            let text = vec![
-                Spans::from("This is a line "),
-                Spans::from(Span::styled("This is a line   ", Style::default().fg(Color::Red))),
-                Spans::from(Span::styled("This is a line", Style::default().bg(Color::Blue))),
-                Spans::from(Span::styled(
-                    "This is a longer line",
-                    Style::default().add_modifier(Modifier::CROSSED_OUT),
-                )),
-                Spans::from(Span::styled(&long_line, Style::default().bg(Color::Green))),
-                Spans::from(Span::styled(
-                    "This is a line",
-                    Style::default().fg(Color::Green).add_modifier(Modifier::ITALIC),
-                )),
-            ];
-
-            let create_block = |title| {
-                Block::default()
-                    .borders(Borders::ALL)
-                    .style(Style::default().bg(Color::White).fg(Color::Black))
-                    .title(Span::styled(title, Style::default().add_modifier(Modifier::BOLD)))
-            };
-            let paragraph = Paragraph::new(text.clone())
-                .style(Style::default().bg(Color::White).fg(Color::Black))
-                .block(create_block("Left, no wrap"))
-                .alignment(Alignment::Left);
-            f.render_widget(paragraph, chunks[0]);
-            let paragraph = Paragraph::new(text.clone())
-                .style(Style::default().bg(Color::White).fg(Color::Black))
-                .block(create_block("Left, wrap"))
-                .alignment(Alignment::Left)
-                .wrap(Wrap { trim: true });
-            f.render_widget(paragraph, chunks[1]);
-            let paragraph = Paragraph::new(text.clone())
-                .style(Style::default().bg(Color::White).fg(Color::Black))
-                .block(create_block("Center, wrap"))
-                .alignment(Alignment::Center)
-                .wrap(Wrap { trim: true })
-                .scroll((scroll, 0));
-            f.render_widget(paragraph, chunks[2]);
-            let paragraph = Paragraph::new(text)
-                .style(Style::default().bg(Color::White).fg(Color::Black))
-                .block(create_block("Right, wrap"))
-                .alignment(Alignment::Right)
-                .wrap(Wrap { trim: true });
-            f.render_widget(paragraph, chunks[3]);
-        })?;
-
-        scroll += 1;
-        scroll %= 10;
-
-        if let Event::Input(key) = events.next()? {
-            if key == Key::Char('q') {
-                break;
-            }
-        }
+    if let Err(err) = res {
+        println!("{:?}", err)
     }
+
     Ok(())
 }
+
+fn run_app<B: Backend>(
+    terminal: &mut Terminal<B>,
+    mut app: App,
+    tick_rate: Duration,
+) -> io::Result<()> {
+    let mut last_tick = Instant::now();
+    loop {
+        terminal.draw(|f| ui(f, &app))?;
+
+        let timeout = tick_rate
+            .checked_sub(last_tick.elapsed())
+            .unwrap_or_else(|| Duration::from_secs(0));
+        if crossterm::event::poll(timeout)? {
+            if let Event::Key(key) = event::read()? {
+                if let KeyCode::Char('q') = key.code {
+                    return Ok(());
+                }
+            }
+        }
+        if last_tick.elapsed() >= tick_rate {
+            app.on_tick();
+            last_tick = Instant::now();
+        }
+    }
+}
+
+fn ui<B: Backend>(f: &mut Frame<B>, app: &App) {
+    let size = f.size();
+
+    // Words made "loooong" to demonstrate line breaking.
+    let s = "Veeeeeeeeeeeeeeeery    loooooooooooooooooong   striiiiiiiiiiiiiiiiiiiiiiiiiing.   ";
+    let mut long_line = s.repeat(usize::from(size.width) / s.len() + 4);
+    long_line.push('\n');
+
+    let block = Block::default().style(Style::default().bg(Color::White).fg(Color::Black));
+    f.render_widget(block, size);
+
+    let chunks = Layout::default()
+        .direction(Direction::Vertical)
+        .margin(5)
+        .constraints(
+            [
+                Constraint::Percentage(25),
+                Constraint::Percentage(25),
+                Constraint::Percentage(25),
+                Constraint::Percentage(25),
+            ]
+            .as_ref(),
+        )
+        .split(size);
+
+    let text = vec![
+        Spans::from("This is a line "),
+        Spans::from(Span::styled(
+            "This is a line   ",
+            Style::default().fg(Color::Red),
+        )),
+        Spans::from(Span::styled(
+            "This is a line",
+            Style::default().bg(Color::Blue),
+        )),
+        Spans::from(Span::styled(
+            "This is a longer line",
+            Style::default().add_modifier(Modifier::CROSSED_OUT),
+        )),
+        Spans::from(Span::styled(&long_line, Style::default().bg(Color::Green))),
+        Spans::from(Span::styled(
+            "This is a line",
+            Style::default()
+                .fg(Color::Green)
+                .add_modifier(Modifier::ITALIC),
+        )),
+    ];
+
+    let create_block = |title| {
+        Block::default()
+            .borders(Borders::ALL)
+            .style(Style::default().bg(Color::White).fg(Color::Black))
+            .title(Span::styled(
+                title,
+                Style::default().add_modifier(Modifier::BOLD),
+            ))
+    };
+    let paragraph = Paragraph::new(text.clone())
+        .style(Style::default().bg(Color::White).fg(Color::Black))
+        .block(create_block("Left, no wrap"))
+        .alignment(Alignment::Left);
+    f.render_widget(paragraph, chunks[0]);
+    let paragraph = Paragraph::new(text.clone())
+        .style(Style::default().bg(Color::White).fg(Color::Black))
+        .block(create_block("Left, wrap"))
+        .alignment(Alignment::Left)
+        .wrap(Wrap { trim: true });
+    f.render_widget(paragraph, chunks[1]);
+    let paragraph = Paragraph::new(text.clone())
+        .style(Style::default().bg(Color::White).fg(Color::Black))
+        .block(create_block("Center, wrap"))
+        .alignment(Alignment::Center)
+        .wrap(Wrap { trim: true })
+        .scroll((app.scroll, 0));
+    f.render_widget(paragraph, chunks[2]);
+    let paragraph = Paragraph::new(text)
+        .style(Style::default().bg(Color::White).fg(Color::Black))
+        .block(create_block("Right, wrap"))
+        .alignment(Alignment::Right)
+        .wrap(Wrap { trim: true });
+    f.render_widget(paragraph, chunks[3]);
+}

examples/popup.rs

@@ -1,20 +1,106 @@
-#[allow(dead_code)]
-mod util;
-
-use crate::util::event::{Event, Events};
 use std::{error::Error, io};
-use termion::{event::Key, input::MouseTerminal, raw::IntoRawMode, screen::AlternateScreen};
 use tui::{
-    backend::TermionBackend,
+    backend::{Backend, CrosstermBackend},
     layout::{Alignment, Constraint, Direction, Layout, Rect},
     style::{Color, Modifier, Style},
-    text::{Span, Spans},
+    text::Span,
     widgets::{Block, Borders, Clear, Paragraph, Wrap},
-    Terminal,
+    Frame, Terminal,
 };
 
-/// helper function to create a centered rect using up
-/// certain percentage of the available rect `r`
+use crossterm::{
+    event::{self, DisableMouseCapture, EnableMouseCapture, Event, KeyCode},
+    execute,
+    terminal::{disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen},
+};
+
+struct App {
+    show_popup: bool,
+}
+
+impl App {
+    fn new() -> App {
+        App { show_popup: false }
+    }
+}
+
+fn main() -> Result<(), Box<dyn Error>> {
+    // setup terminal
+    enable_raw_mode()?;
+    let mut stdout = io::stdout();
+    execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
+    let backend = CrosstermBackend::new(stdout);
+    let mut terminal = Terminal::new(backend)?;
+
+    // create app and run it
+    let app = App::new();
+    let res = run_app(&mut terminal, app);
+
+    // restore terminal
+    disable_raw_mode()?;
+    execute!(
+        terminal.backend_mut(),
+        LeaveAlternateScreen,
+        DisableMouseCapture
+    )?;
+    terminal.show_cursor()?;
+
+    if let Err(err) = res {
+        println!("{:?}", err)
+    }
+
+    Ok(())
+}
+
+fn run_app<B: Backend>(terminal: &mut Terminal<B>, mut app: App) -> io::Result<()> {
+    loop {
+        terminal.draw(|f| ui(f, &app))?;
+
+        if let Event::Key(key) = event::read()? {
+            match key.code {
+                KeyCode::Char('q') => return Ok(()),
+                KeyCode::Char('p') => app.show_popup = !app.show_popup,
+                _ => {}
+            }
+        }
+    }
+}
+
+fn ui<B: Backend>(f: &mut Frame<B>, app: &App) {
+    let size = f.size();
+
+    let chunks = Layout::default()
+        .constraints([Constraint::Percentage(20), Constraint::Percentage(80)].as_ref())
+        .split(size);
+
+    let text = if app.show_popup {
+        "Press p to close the popup"
+    } else {
+        "Press p to show the popup"
+    };
+    let paragraph = Paragraph::new(Span::styled(
+        text,
+        Style::default().add_modifier(Modifier::SLOW_BLINK),
+    ))
+    .alignment(Alignment::Center)
+    .wrap(Wrap { trim: true });
+    f.render_widget(paragraph, chunks[0]);
+
+    let block = Block::default()
+        .title("Content")
+        .borders(Borders::ALL)
+        .style(Style::default().bg(Color::Blue));
+    f.render_widget(block, chunks[1]);
+
+    if app.show_popup {
+        let block = Block::default().title("Popup").borders(Borders::ALL);
+        let area = centered_rect(60, 20, size);
+        f.render_widget(Clear, area); //this clears out the background
+        f.render_widget(block, area);
+    }
+}
+
+/// helper function to create a centered rect using up certain percentage of the available rect `r`
 fn centered_rect(percent_x: u16, percent_y: u16, r: Rect) -> Rect {
     let popup_layout = Layout::default()
         .direction(Direction::Vertical)
@@ -40,67 +126,3 @@ fn centered_rect(percent_x: u16, percent_y: u16, r: Rect) -> Rect {
         )
         .split(popup_layout[1])[1]
 }
-
-fn main() -> Result<(), Box<dyn Error>> {
-    // Terminal initialization
-    let stdout = io::stdout().into_raw_mode()?;
-    let stdout = MouseTerminal::from(stdout);
-    let stdout = AlternateScreen::from(stdout);
-    let backend = TermionBackend::new(stdout);
-    let mut terminal = Terminal::new(backend)?;
-
-    let events = Events::new();
-
-    loop {
-        terminal.draw(|f| {
-            let size = f.size();
-
-            let chunks = Layout::default()
-                .direction(Direction::Horizontal)
-                .constraints([Constraint::Percentage(50), Constraint::Percentage(50)].as_ref())
-                .split(size);
-
-                let s = "Veeeeeeeeeeeeeeeery    loooooooooooooooooong   striiiiiiiiiiiiiiiiiiiiiiiiiing.   ";
-                let mut long_line = s.repeat(usize::from(size.width)*usize::from(size.height)/300);
-                long_line.push('\n');
-
-            let text = vec![
-                Spans::from("This is a line "),
-                Spans::from(Span::styled("This is a line   ", Style::default().fg(Color::Red))),
-                Spans::from(Span::styled("This is a line", Style::default().bg(Color::Blue))),
-                Spans::from(Span::styled(
-                    "This is a longer line\n",
-                    Style::default().add_modifier(Modifier::CROSSED_OUT),
-                )),
-                Spans::from(Span::styled(&long_line, Style::default().bg(Color::Green))),
-                Spans::from(Span::styled(
-                    "This is a line\n",
-                    Style::default().fg(Color::Green).add_modifier(Modifier::ITALIC),
-                )),
-            ];
-
-            let paragraph = Paragraph::new(text.clone())
-                .block(Block::default().title("Left Block").borders(Borders::ALL))
-                .alignment(Alignment::Left).wrap(Wrap { trim: true });
-            f.render_widget(paragraph, chunks[0]);
-
-            let paragraph = Paragraph::new(text)
-                .block(Block::default().title("Right Block").borders(Borders::ALL))
-                .alignment(Alignment::Left).wrap(Wrap { trim: true });
-            f.render_widget(paragraph, chunks[1]);
-
-            let block = Block::default().title("Popup").borders(Borders::ALL);
-            let area = centered_rect(60, 20, size);
-            f.render_widget(Clear, area); //this clears out the background
-            f.render_widget(block, area);
-        })?;
-
-        if let Event::Input(input) = events.next()? {
-            if let Key::Char('q') = input {
-                break;
-            }
-        }
-    }
-
-    Ok(())
-}

examples/rustbox_demo.rs

@@ -1,68 +0,0 @@
-mod demo;
-#[allow(dead_code)]
-mod util;
-
-use crate::demo::{ui, App};
-use argh::FromArgs;
-use rustbox::keyboard::Key;
-use std::{
-    error::Error,
-    time::{Duration, Instant},
-};
-use tui::{backend::RustboxBackend, Terminal};
-
-/// Rustbox demo
-#[derive(Debug, FromArgs)]
-struct Cli {
-    /// time in ms between two ticks.
-    #[argh(option, default = "250")]
-    tick_rate: u64,
-    /// whether unicode symbols are used to improve the overall look of the app
-    #[argh(option, default = "true")]
-    enhanced_graphics: bool,
-}
-
-fn main() -> Result<(), Box<dyn Error>> {
-    let cli: Cli = argh::from_env();
-
-    let backend = RustboxBackend::new()?;
-    let mut terminal = Terminal::new(backend)?;
-
-    let mut app = App::new("Rustbox demo", cli.enhanced_graphics);
-
-    let mut last_tick = Instant::now();
-    let tick_rate = Duration::from_millis(cli.tick_rate);
-    loop {
-        terminal.draw(|f| ui::draw(f, &mut app))?;
-        if let Ok(rustbox::Event::KeyEvent(key)) =
-            terminal.backend().rustbox().peek_event(tick_rate, false)
-        {
-            match key {
-                Key::Char(c) => {
-                    app.on_key(c);
-                }
-                Key::Up => {
-                    app.on_up();
-                }
-                Key::Down => {
-                    app.on_down();
-                }
-                Key::Left => {
-                    app.on_left();
-                }
-                Key::Right => {
-                    app.on_right();
-                }
-                _ => {}
-            }
-        }
-        if last_tick.elapsed() > tick_rate {
-            app.on_tick();
-            last_tick = Instant::now();
-        }
-        if app.should_quit {
-            break;
-        }
-    }
-    Ok(())
-}

examples/sparkline.rs

@@ -1,20 +1,47 @@
-#[allow(dead_code)]
-mod util;
-
-use crate::util::{
-    event::{Event, Events},
-    RandomSignal,
+use crossterm::{
+    event::{self, DisableMouseCapture, EnableMouseCapture, Event, KeyCode},
+    execute,
+    terminal::{disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen},
+};
+use rand::{
+    distributions::{Distribution, Uniform},
+    rngs::ThreadRng,
+};
+use std::{
+    error::Error,
+    io,
+    time::{Duration, Instant},
 };
-use std::{error::Error, io};
-use termion::{event::Key, input::MouseTerminal, raw::IntoRawMode, screen::AlternateScreen};
 use tui::{
-    backend::TermionBackend,
+    backend::{Backend, CrosstermBackend},
     layout::{Constraint, Direction, Layout},
     style::{Color, Style},
     widgets::{Block, Borders, Sparkline},
-    Terminal,
+    Frame, Terminal,
 };
 
+#[derive(Clone)]
+pub struct RandomSignal {
+    distribution: Uniform<u64>,
+    rng: ThreadRng,
+}
+
+impl RandomSignal {
+    pub fn new(lower: u64, upper: u64) -> RandomSignal {
+        RandomSignal {
+            distribution: Uniform::new(lower, upper),
+            rng: rand::thread_rng(),
+        }
+    }
+}
+
+impl Iterator for RandomSignal {
+    type Item = u64;
+    fn next(&mut self) -> Option<u64> {
+        Some(self.distribution.sample(&mut self.rng))
+    }
+}
+
 struct App {
     signal: RandomSignal,
     data1: Vec<u64>,
@@ -36,7 +63,7 @@ impl App {
         }
     }
 
-    fn update(&mut self) {
+    fn on_tick(&mut self) {
         let value = self.signal.next().unwrap();
         self.data1.pop();
         self.data1.insert(0, value);
@@ -50,75 +77,100 @@ impl App {
 }
 
 fn main() -> Result<(), Box<dyn Error>> {
-    // Terminal initialization
-    let stdout = io::stdout().into_raw_mode()?;
-    let stdout = MouseTerminal::from(stdout);
-    let stdout = AlternateScreen::from(stdout);
-    let backend = TermionBackend::new(stdout);
+    // setup terminal
+    enable_raw_mode()?;
+    let mut stdout = io::stdout();
+    execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
+    let backend = CrosstermBackend::new(stdout);
     let mut terminal = Terminal::new(backend)?;
 
-    // Setup event handlers
-    let events = Events::new();
+    // create app and run it
+    let tick_rate = Duration::from_millis(250);
+    let app = App::new();
+    let res = run_app(&mut terminal, app, tick_rate);
 
-    // Create default app state
-    let mut app = App::new();
+    // restore terminal
+    disable_raw_mode()?;
+    execute!(
+        terminal.backend_mut(),
+        LeaveAlternateScreen,
+        DisableMouseCapture
+    )?;
+    terminal.show_cursor()?;
 
-    loop {
-        terminal.draw(|f| {
-            let chunks = Layout::default()
-                .direction(Direction::Vertical)
-                .margin(2)
-                .constraints(
-                    [
-                        Constraint::Length(3),
-                        Constraint::Length(3),
-                        Constraint::Length(7),
-                        Constraint::Min(0),
-                    ]
-                    .as_ref(),
-                )
-                .split(f.size());
-            let sparkline = Sparkline::default()
-                .block(
-                    Block::default()
-                        .title("Data1")
-                        .borders(Borders::LEFT | Borders::RIGHT),
-                )
-                .data(&app.data1)
-                .style(Style::default().fg(Color::Yellow));
-            f.render_widget(sparkline, chunks[0]);
-            let sparkline = Sparkline::default()
-                .block(
-                    Block::default()
-                        .title("Data2")
-                        .borders(Borders::LEFT | Borders::RIGHT),
-                )
-                .data(&app.data2)
-                .style(Style::default().bg(Color::Green));
-            f.render_widget(sparkline, chunks[1]);
-            // Multiline
-            let sparkline = Sparkline::default()
-                .block(
-                    Block::default()
-                        .title("Data3")
-                        .borders(Borders::LEFT | Borders::RIGHT),
-                )
-                .data(&app.data3)
-                .style(Style::default().fg(Color::Red));
-            f.render_widget(sparkline, chunks[2]);
-        })?;
-
-        match events.next()? {
-            Event::Input(input) => {
-                if input == Key::Char('q') {
-                    break;
-                }
-            }
-            Event::Tick => {
-                app.update();
-            }
-        }
+    if let Err(err) = res {
+        println!("{:?}", err)
     }
 
     Ok(())
 }
+
+fn run_app<B: Backend>(
+    terminal: &mut Terminal<B>,
+    mut app: App,
+    tick_rate: Duration,
+) -> io::Result<()> {
+    let mut last_tick = Instant::now();
+    loop {
+        terminal.draw(|f| ui(f, &app))?;
+
+        let timeout = tick_rate
+            .checked_sub(last_tick.elapsed())
+            .unwrap_or_else(|| Duration::from_secs(0));
+        if crossterm::event::poll(timeout)? {
+            if let Event::Key(key) = event::read()? {
+                if let KeyCode::Char('q') = key.code {
+                    return Ok(());
+                }
+            }
+        }
+        if last_tick.elapsed() >= tick_rate {
+            app.on_tick();
+            last_tick = Instant::now();
+        }
+    }
+}
+
+fn ui<B: Backend>(f: &mut Frame<B>, app: &App) {
+    let chunks = Layout::default()
+        .direction(Direction::Vertical)
+        .margin(2)
+        .constraints(
+            [
+                Constraint::Length(3),
+                Constraint::Length(3),
+                Constraint::Length(7),
+                Constraint::Min(0),
+            ]
+            .as_ref(),
+        )
+        .split(f.size());
+    let sparkline = Sparkline::default()
+        .block(
+            Block::default()
+                .title("Data1")
+                .borders(Borders::LEFT | Borders::RIGHT),
+        )
+        .data(&app.data1)
+        .style(Style::default().fg(Color::Yellow));
+    f.render_widget(sparkline, chunks[0]);
+    let sparkline = Sparkline::default()
+        .block(
+            Block::default()
+                .title("Data2")
+                .borders(Borders::LEFT | Borders::RIGHT),
+        )
+        .data(&app.data2)
+        .style(Style::default().bg(Color::Green));
+    f.render_widget(sparkline, chunks[1]);
+    // Multiline
+    let sparkline = Sparkline::default()
+        .block(
+            Block::default()
+                .title("Data3")
+                .borders(Borders::LEFT | Borders::RIGHT),
+        )
+        .data(&app.data3)
+        .style(Style::default().fg(Color::Red));
+    f.render_widget(sparkline, chunks[2]);
+}

examples/table.rs

@@ -1,25 +1,25 @@
-#[allow(dead_code)]
-mod util;
-
-use crate::util::event::{Event, Events};
+use crossterm::{
+    event::{self, DisableMouseCapture, EnableMouseCapture, Event, KeyCode},
+    execute,
+    terminal::{disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen},
+};
 use std::{error::Error, io};
-use termion::{event::Key, input::MouseTerminal, raw::IntoRawMode, screen::AlternateScreen};
 use tui::{
-    backend::TermionBackend,
+    backend::{Backend, CrosstermBackend},
     layout::{Constraint, Layout},
     style::{Color, Modifier, Style},
     widgets::{Block, Borders, Cell, Row, Table, TableState},
-    Terminal,
+    Frame, Terminal,
 };
 
-pub struct StatefulTable<'a> {
+struct App<'a> {
     state: TableState,
     items: Vec<Vec<&'a str>>,
 }
 
-impl<'a> StatefulTable<'a> {
-    fn new() -> StatefulTable<'a> {
-        StatefulTable {
+impl<'a> App<'a> {
+    fn new() -> App<'a> {
+        App {
             state: TableState::default(),
             items: vec![
                 vec!["Row11", "Row12", "Row13"],
@@ -74,72 +74,82 @@ impl<'a> StatefulTable<'a> {
 }
 
 fn main() -> Result<(), Box<dyn Error>> {
-    // Terminal initialization
-    let stdout = io::stdout().into_raw_mode()?;
-    let stdout = MouseTerminal::from(stdout);
-    let stdout = AlternateScreen::from(stdout);
-    let backend = TermionBackend::new(stdout);
+    // setup terminal
+    enable_raw_mode()?;
+    let mut stdout = io::stdout();
+    execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
+    let backend = CrosstermBackend::new(stdout);
     let mut terminal = Terminal::new(backend)?;
 
-    let events = Events::new();
+    // create app and run it
+    let app = App::new();
+    let res = run_app(&mut terminal, app);
 
-    let mut table = StatefulTable::new();
+    // restore terminal
+    disable_raw_mode()?;
+    execute!(
+        terminal.backend_mut(),
+        LeaveAlternateScreen,
+        DisableMouseCapture
+    )?;
+    terminal.show_cursor()?;
 
-    // Input
-    loop {
-        terminal.draw(|f| {
-            let rects = Layout::default()
-                .constraints([Constraint::Percentage(100)].as_ref())
-                .margin(5)
-                .split(f.size());
-
-            let selected_style = Style::default().add_modifier(Modifier::REVERSED);
-            let normal_style = Style::default().bg(Color::Blue);
-            let header_cells = ["Header1", "Header2", "Header3"]
-                .iter()
-                .map(|h| Cell::from(*h).style(Style::default().fg(Color::Red)));
-            let header = Row::new(header_cells)
-                .style(normal_style)
-                .height(1)
-                .bottom_margin(1);
-            let rows = table.items.iter().map(|item| {
-                let height = item
-                    .iter()
-                    .map(|content| content.chars().filter(|c| *c == '\n').count())
-                    .max()
-                    .unwrap_or(0)
-                    + 1;
-                let cells = item.iter().map(|c| Cell::from(*c));
-                Row::new(cells).height(height as u16).bottom_margin(1)
-            });
-            let t = Table::new(rows)
-                .header(header)
-                .block(Block::default().borders(Borders::ALL).title("Table"))
-                .highlight_style(selected_style)
-                .highlight_symbol(">> ")
-                .widths(&[
-                    Constraint::Percentage(50),
-                    Constraint::Length(30),
-                    Constraint::Max(10),
-                ]);
-            f.render_stateful_widget(t, rects[0], &mut table.state);
-        })?;
-
-        if let Event::Input(key) = events.next()? {
-            match key {
-                Key::Char('q') => {
-                    break;
-                }
-                Key::Down => {
-                    table.next();
-                }
-                Key::Up => {
-                    table.previous();
-                }
-                _ => {}
-            }
-        };
+    if let Err(err) = res {
+        println!("{:?}", err)
     }
 
     Ok(())
 }
+
+fn run_app<B: Backend>(terminal: &mut Terminal<B>, mut app: App) -> io::Result<()> {
+    loop {
+        terminal.draw(|f| ui(f, &mut app))?;
+
+        if let Event::Key(key) = event::read()? {
+            match key.code {
+                KeyCode::Char('q') => return Ok(()),
+                KeyCode::Down => app.next(),
+                KeyCode::Up => app.previous(),
+                _ => {}
+            }
+        }
+    }
+}
+
+fn ui<B: Backend>(f: &mut Frame<B>, app: &mut App) {
+    let rects = Layout::default()
+        .constraints([Constraint::Percentage(100)].as_ref())
+        .margin(5)
+        .split(f.size());
+
+    let selected_style = Style::default().add_modifier(Modifier::REVERSED);
+    let normal_style = Style::default().bg(Color::Blue);
+    let header_cells = ["Header1", "Header2", "Header3"]
+        .iter()
+        .map(|h| Cell::from(*h).style(Style::default().fg(Color::Red)));
+    let header = Row::new(header_cells)
+        .style(normal_style)
+        .height(1)
+        .bottom_margin(1);
+    let rows = app.items.iter().map(|item| {
+        let height = item
+            .iter()
+            .map(|content| content.chars().filter(|c| *c == '\n').count())
+            .max()
+            .unwrap_or(0)
+            + 1;
+        let cells = item.iter().map(|c| Cell::from(*c));
+        Row::new(cells).height(height as u16).bottom_margin(1)
+    });
+    let t = Table::new(rows)
+        .header(header)
+        .block(Block::default().borders(Borders::ALL).title("Table"))
+        .highlight_style(selected_style)
+        .highlight_symbol(">> ")
+        .widths(&[
+            Constraint::Percentage(50),
+            Constraint::Length(30),
+            Constraint::Min(10),
+        ]);
+    f.render_stateful_widget(t, rects[0], &mut app.state);
+}

examples/tabs.rs

@@ -1,94 +1,124 @@
-#[allow(dead_code)]
-mod util;
-
-use crate::util::{
-    event::{Event, Events},
-    TabsState,
+use crossterm::{
+    event::{self, DisableMouseCapture, EnableMouseCapture, Event, KeyCode},
+    execute,
+    terminal::{disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen},
 };
 use std::{error::Error, io};
-use termion::{event::Key, input::MouseTerminal, raw::IntoRawMode, screen::AlternateScreen};
 use tui::{
-    backend::TermionBackend,
+    backend::{Backend, CrosstermBackend},
     layout::{Constraint, Direction, Layout},
     style::{Color, Modifier, Style},
     text::{Span, Spans},
     widgets::{Block, Borders, Tabs},
-    Terminal,
+    Frame, Terminal,
 };
 
 struct App<'a> {
-    tabs: TabsState<'a>,
+    pub titles: Vec<&'a str>,
+    pub index: usize,
+}
+
+impl<'a> App<'a> {
+    fn new() -> App<'a> {
+        App {
+            titles: vec!["Tab0", "Tab1", "Tab2", "Tab3"],
+            index: 0,
+        }
+    }
+
+    pub fn next(&mut self) {
+        self.index = (self.index + 1) % self.titles.len();
+    }
+
+    pub fn previous(&mut self) {
+        if self.index > 0 {
+            self.index -= 1;
+        } else {
+            self.index = self.titles.len() - 1;
+        }
+    }
 }
 
 fn main() -> Result<(), Box<dyn Error>> {
-    // Terminal initialization
-    let stdout = io::stdout().into_raw_mode()?;
-    let stdout = MouseTerminal::from(stdout);
-    let stdout = AlternateScreen::from(stdout);
-    let backend = TermionBackend::new(stdout);
+    // setup terminal
+    enable_raw_mode()?;
+    let mut stdout = io::stdout();
+    execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
+    let backend = CrosstermBackend::new(stdout);
     let mut terminal = Terminal::new(backend)?;
 
-    let events = Events::new();
+    // create app and run it
+    let app = App::new();
+    let res = run_app(&mut terminal, app);
 
-    // App
-    let mut app = App {
-        tabs: TabsState::new(vec!["Tab0", "Tab1", "Tab2", "Tab3"]),
-    };
+    // restore terminal
+    disable_raw_mode()?;
+    execute!(
+        terminal.backend_mut(),
+        LeaveAlternateScreen,
+        DisableMouseCapture
+    )?;
+    terminal.show_cursor()?;
 
-    // Main loop
+    if let Err(err) = res {
+        println!("{:?}", err)
+    }
+
+    Ok(())
+}
+
+fn run_app<B: Backend>(terminal: &mut Terminal<B>, mut app: App) -> io::Result<()> {
     loop {
-        terminal.draw(|f| {
-            let size = f.size();
-            let chunks = Layout::default()
-                .direction(Direction::Vertical)
-                .margin(5)
-                .constraints([Constraint::Length(3), Constraint::Min(0)].as_ref())
-                .split(size);
+        terminal.draw(|f| ui(f, &app))?;
 
-            let block = Block::default().style(Style::default().bg(Color::White).fg(Color::Black));
-            f.render_widget(block, size);
-            let titles = app
-                .tabs
-                .titles
-                .iter()
-                .map(|t| {
-                    let (first, rest) = t.split_at(1);
-                    Spans::from(vec![
-                        Span::styled(first, Style::default().fg(Color::Yellow)),
-                        Span::styled(rest, Style::default().fg(Color::Green)),
-                    ])
-                })
-                .collect();
-            let tabs = Tabs::new(titles)
-                .block(Block::default().borders(Borders::ALL).title("Tabs"))
-                .select(app.tabs.index)
-                .style(Style::default().fg(Color::Cyan))
-                .highlight_style(
-                    Style::default()
-                        .add_modifier(Modifier::BOLD)
-                        .bg(Color::Black),
-                );
-            f.render_widget(tabs, chunks[0]);
-            let inner = match app.tabs.index {
-                0 => Block::default().title("Inner 0").borders(Borders::ALL),
-                1 => Block::default().title("Inner 1").borders(Borders::ALL),
-                2 => Block::default().title("Inner 2").borders(Borders::ALL),
-                3 => Block::default().title("Inner 3").borders(Borders::ALL),
-                _ => unreachable!(),
-            };
-            f.render_widget(inner, chunks[1]);
-        })?;
-
-        if let Event::Input(input) = events.next()? {
-            match input {
-                Key::Char('q') => {
-                    break;
-                }
-                Key::Right => app.tabs.next(),
-                Key::Left => app.tabs.previous(),
+        if let Event::Key(key) = event::read()? {
+            match key.code {
+                KeyCode::Char('q') => return Ok(()),
+                KeyCode::Right => app.next(),
+                KeyCode::Left => app.previous(),
                 _ => {}
             }
         }
     }
-    Ok(())
+}
+
+fn ui<B: Backend>(f: &mut Frame<B>, app: &App) {
+    let size = f.size();
+    let chunks = Layout::default()
+        .direction(Direction::Vertical)
+        .margin(5)
+        .constraints([Constraint::Length(3), Constraint::Min(0)].as_ref())
+        .split(size);
+
+    let block = Block::default().style(Style::default().bg(Color::White).fg(Color::Black));
+    f.render_widget(block, size);
+    let titles = app
+        .titles
+        .iter()
+        .map(|t| {
+            let (first, rest) = t.split_at(1);
+            Spans::from(vec![
+                Span::styled(first, Style::default().fg(Color::Yellow)),
+                Span::styled(rest, Style::default().fg(Color::Green)),
+            ])
+        })
+        .collect();
+    let tabs = Tabs::new(titles)
+        .block(Block::default().borders(Borders::ALL).title("Tabs"))
+        .select(app.index)
+        .style(Style::default().fg(Color::Cyan))
+        .highlight_style(
+            Style::default()
+                .add_modifier(Modifier::BOLD)
+                .bg(Color::Black),
+        );
+    f.render_widget(tabs, chunks[0]);
+    let inner = match app.index {
+        0 => Block::default().title("Inner 0").borders(Borders::ALL),
+        1 => Block::default().title("Inner 1").borders(Borders::ALL),
+        2 => Block::default().title("Inner 2").borders(Borders::ALL),
+        3 => Block::default().title("Inner 3").borders(Borders::ALL),
+        _ => unreachable!(),
+    };
+    f.render_widget(inner, chunks[1]);
 }

examples/termion_demo.rs

@@ -1,72 +0,0 @@
-mod demo;
-#[allow(dead_code)]
-mod util;
-
-use crate::{
-    demo::{ui, App},
-    util::event::{Config, Event, Events},
-};
-use argh::FromArgs;
-use std::{error::Error, io, time::Duration};
-use termion::{event::Key, input::MouseTerminal, raw::IntoRawMode, screen::AlternateScreen};
-use tui::{backend::TermionBackend, Terminal};
-
-/// Termion demo
-#[derive(Debug, FromArgs)]
-struct Cli {
-    /// time in ms between two ticks.
-    #[argh(option, default = "250")]
-    tick_rate: u64,
-    /// whether unicode symbols are used to improve the overall look of the app
-    #[argh(option, default = "true")]
-    enhanced_graphics: bool,
-}
-
-fn main() -> Result<(), Box<dyn Error>> {
-    let cli: Cli = argh::from_env();
-
-    let events = Events::with_config(Config {
-        tick_rate: Duration::from_millis(cli.tick_rate),
-        ..Config::default()
-    });
-
-    let stdout = io::stdout().into_raw_mode()?;
-    let stdout = MouseTerminal::from(stdout);
-    let stdout = AlternateScreen::from(stdout);
-    let backend = TermionBackend::new(stdout);
-    let mut terminal = Terminal::new(backend)?;
-
-    let mut app = App::new("Termion demo", cli.enhanced_graphics);
-    loop {
-        terminal.draw(|f| ui::draw(f, &mut app))?;
-
-        match events.next()? {
-            Event::Input(key) => match key {
-                Key::Char(c) => {
-                    app.on_key(c);
-                }
-                Key::Up => {
-                    app.on_up();
-                }
-                Key::Down => {
-                    app.on_down();
-                }
-                Key::Left => {
-                    app.on_left();
-                }
-                Key::Right => {
-                    app.on_right();
-                }
-                _ => {}
-            },
-            Event::Tick => {
-                app.on_tick();
-            }
-        }
-        if app.should_quit {
-            break;
-        }
-    }
-
-    Ok(())
-}

examples/user_input.rs

@@ -9,20 +9,19 @@
 ///   * Pressing Backspace erases a character
 ///   * Pressing Enter pushes the current input in the history of previous
 ///   messages
-
-#[allow(dead_code)]
-mod util;
-
-use crate::util::event::{Event, Events};
+use crossterm::{
+    event::{self, DisableMouseCapture, EnableMouseCapture, Event, KeyCode},
+    execute,
+    terminal::{disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen},
+};
 use std::{error::Error, io};
-use termion::{event::Key, input::MouseTerminal, raw::IntoRawMode, screen::AlternateScreen};
 use tui::{
-    backend::TermionBackend,
+    backend::{Backend, CrosstermBackend},
     layout::{Constraint, Direction, Layout},
     style::{Color, Modifier, Style},
     text::{Span, Spans, Text},
     widgets::{Block, Borders, List, ListItem, Paragraph},
-    Terminal,
+    Frame, Terminal,
 };
 use unicode_width::UnicodeWidthStr;
 
@@ -52,122 +51,59 @@ impl Default for App {
 }
 
 fn main() -> Result<(), Box<dyn Error>> {
-    // Terminal initialization
-    let stdout = io::stdout().into_raw_mode()?;
-    let stdout = MouseTerminal::from(stdout);
-    let stdout = AlternateScreen::from(stdout);
-    let backend = TermionBackend::new(stdout);
+    // setup terminal
+    enable_raw_mode()?;
+    let mut stdout = io::stdout();
+    execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
+    let backend = CrosstermBackend::new(stdout);
     let mut terminal = Terminal::new(backend)?;
 
-    // Setup event handlers
-    let events = Events::new();
+    // create app and run it
+    let app = App::default();
+    let res = run_app(&mut terminal, app);
 
-    // Create default app state
-    let mut app = App::default();
+    // restore terminal
+    disable_raw_mode()?;
+    execute!(
+        terminal.backend_mut(),
+        LeaveAlternateScreen,
+        DisableMouseCapture
+    )?;
+    terminal.show_cursor()?;
 
+    if let Err(err) = res {
+        println!("{:?}", err)
+    }
+
+    Ok(())
+}
+
+fn run_app<B: Backend>(terminal: &mut Terminal<B>, mut app: App) -> io::Result<()> {
     loop {
-        // Draw UI
-        terminal.draw(|f| {
-            let chunks = Layout::default()
-                .direction(Direction::Vertical)
-                .margin(2)
-                .constraints(
-                    [
-                        Constraint::Length(1),
-                        Constraint::Length(3),
-                        Constraint::Min(1),
-                    ]
-                    .as_ref(),
-                )
-                .split(f.size());
+        terminal.draw(|f| ui(f, &app))?;
 
-            let (msg, style) = match app.input_mode {
-                InputMode::Normal => (
-                    vec![
-                        Span::raw("Press "),
-                        Span::styled("q", Style::default().add_modifier(Modifier::BOLD)),
-                        Span::raw(" to exit, "),
-                        Span::styled("e", Style::default().add_modifier(Modifier::BOLD)),
-                        Span::raw(" to start editing."),
-                    ],
-                    Style::default().add_modifier(Modifier::RAPID_BLINK),
-                ),
-                InputMode::Editing => (
-                    vec![
-                        Span::raw("Press "),
-                        Span::styled("Esc", Style::default().add_modifier(Modifier::BOLD)),
-                        Span::raw(" to stop editing, "),
-                        Span::styled("Enter", Style::default().add_modifier(Modifier::BOLD)),
-                        Span::raw(" to record the message"),
-                    ],
-                    Style::default(),
-                ),
-            };
-            let mut text = Text::from(Spans::from(msg));
-            text.patch_style(style);
-            let help_message = Paragraph::new(text);
-            f.render_widget(help_message, chunks[0]);
-
-            let input = Paragraph::new(app.input.as_ref())
-                .style(match app.input_mode {
-                    InputMode::Normal => Style::default(),
-                    InputMode::Editing => Style::default().fg(Color::Yellow),
-                })
-                .block(Block::default().borders(Borders::ALL).title("Input"));
-            f.render_widget(input, chunks[1]);
+        if let Event::Key(key) = event::read()? {
             match app.input_mode {
-                InputMode::Normal =>
-                    // Hide the cursor. `Frame` does this by default, so we don't need to do anything here
-                    {}
-
-                InputMode::Editing => {
-                    // Make the cursor visible and ask tui-rs to put it at the specified coordinates after rendering
-                    f.set_cursor(
-                        // Put cursor past the end of the input text
-                        chunks[1].x + app.input.width() as u16 + 1,
-                        // Move one line down, from the border to the input line
-                        chunks[1].y + 1,
-                    )
-                }
-            }
-
-            let messages: Vec<ListItem> = app
-                .messages
-                .iter()
-                .enumerate()
-                .map(|(i, m)| {
-                    let content = vec![Spans::from(Span::raw(format!("{}: {}", i, m)))];
-                    ListItem::new(content)
-                })
-                .collect();
-            let messages =
-                List::new(messages).block(Block::default().borders(Borders::ALL).title("Messages"));
-            f.render_widget(messages, chunks[2]);
-        })?;
-
-        // Handle input
-        if let Event::Input(input) = events.next()? {
-            match app.input_mode {
-                InputMode::Normal => match input {
-                    Key::Char('e') => {
+                InputMode::Normal => match key.code {
+                    KeyCode::Char('e') => {
                         app.input_mode = InputMode::Editing;
                     }
-                    Key::Char('q') => {
-                        break;
+                    KeyCode::Char('q') => {
+                        return Ok(());
                     }
                     _ => {}
                 },
-                InputMode::Editing => match input {
-                    Key::Char('\n') => {
+                InputMode::Editing => match key.code {
+                    KeyCode::Enter => {
                         app.messages.push(app.input.drain(..).collect());
                     }
-                    Key::Char(c) => {
+                    KeyCode::Char(c) => {
                         app.input.push(c);
                     }
-                    Key::Backspace => {
+                    KeyCode::Backspace => {
                         app.input.pop();
                     }
-                    Key::Esc => {
+                    KeyCode::Esc => {
                         app.input_mode = InputMode::Normal;
                     }
                     _ => {}
@@ -175,5 +111,82 @@ fn main() -> Result<(), Box<dyn Error>> {
             }
         }
     }
-    Ok(())
+}
+
+fn ui<B: Backend>(f: &mut Frame<B>, app: &App) {
+    let chunks = Layout::default()
+        .direction(Direction::Vertical)
+        .margin(2)
+        .constraints(
+            [
+                Constraint::Length(1),
+                Constraint::Length(3),
+                Constraint::Min(1),
+            ]
+            .as_ref(),
+        )
+        .split(f.size());
+
+    let (msg, style) = match app.input_mode {
+        InputMode::Normal => (
+            vec![
+                Span::raw("Press "),
+                Span::styled("q", Style::default().add_modifier(Modifier::BOLD)),
+                Span::raw(" to exit, "),
+                Span::styled("e", Style::default().add_modifier(Modifier::BOLD)),
+                Span::raw(" to start editing."),
+            ],
+            Style::default().add_modifier(Modifier::RAPID_BLINK),
+        ),
+        InputMode::Editing => (
+            vec![
+                Span::raw("Press "),
+                Span::styled("Esc", Style::default().add_modifier(Modifier::BOLD)),
+                Span::raw(" to stop editing, "),
+                Span::styled("Enter", Style::default().add_modifier(Modifier::BOLD)),
+                Span::raw(" to record the message"),
+            ],
+            Style::default(),
+        ),
+    };
+    let mut text = Text::from(Spans::from(msg));
+    text.patch_style(style);
+    let help_message = Paragraph::new(text);
+    f.render_widget(help_message, chunks[0]);
+
+    let input = Paragraph::new(app.input.as_ref())
+        .style(match app.input_mode {
+            InputMode::Normal => Style::default(),
+            InputMode::Editing => Style::default().fg(Color::Yellow),
+        })
+        .block(Block::default().borders(Borders::ALL).title("Input"));
+    f.render_widget(input, chunks[1]);
+    match app.input_mode {
+        InputMode::Normal =>
+            // Hide the cursor. `Frame` does this by default, so we don't need to do anything here
+            {}
+
+        InputMode::Editing => {
+            // Make the cursor visible and ask tui-rs to put it at the specified coordinates after rendering
+            f.set_cursor(
+                // Put cursor past the end of the input text
+                chunks[1].x + app.input.width() as u16 + 1,
+                // Move one line down, from the border to the input line
+                chunks[1].y + 1,
+            )
+        }
+    }
+
+    let messages: Vec<ListItem> = app
+        .messages
+        .iter()
+        .enumerate()
+        .map(|(i, m)| {
+            let content = vec![Spans::from(Span::raw(format!("{}: {}", i, m)))];
+            ListItem::new(content)
+        })
+        .collect();
+    let messages =
+        List::new(messages).block(Block::default().borders(Borders::ALL).title("Messages"));
+    f.render_widget(messages, chunks[2]);
 }

examples/util/event.rs

@@ -1,75 +0,0 @@
-use std::io;
-use std::sync::mpsc;
-use std::thread;
-use std::time::Duration;
-
-use termion::event::Key;
-use termion::input::TermRead;
-
-pub enum Event<I> {
-    Input(I),
-    Tick,
-}
-
-/// A small event handler that wrap termion input and tick events. Each event
-/// type is handled in its own thread and returned to a common `Receiver`
-pub struct Events {
-    rx: mpsc::Receiver<Event<Key>>,
-    input_handle: thread::JoinHandle<()>,
-    tick_handle: thread::JoinHandle<()>,
-}
-
-#[derive(Debug, Clone, Copy)]
-pub struct Config {
-    pub tick_rate: Duration,
-}
-
-impl Default for Config {
-    fn default() -> Config {
-        Config {
-            tick_rate: Duration::from_millis(250),
-        }
-    }
-}
-
-impl Events {
-    pub fn new() -> Events {
-        Events::with_config(Config::default())
-    }
-
-    pub fn with_config(config: Config) -> Events {
-        let (tx, rx) = mpsc::channel();
-        let input_handle = {
-            let tx = tx.clone();
-            thread::spawn(move || {
-                let stdin = io::stdin();
-                for evt in stdin.keys() {
-                    if let Ok(key) = evt {
-                        if let Err(err) = tx.send(Event::Input(key)) {
-                            eprintln!("{}", err);
-                            return;
-                        }
-                    }
-                }
-            })
-        };
-        let tick_handle = {
-            thread::spawn(move || loop {
-                if let Err(err) = tx.send(Event::Tick) {
-                    eprintln!("{}", err);
-                    break;
-                }
-                thread::sleep(config.tick_rate);
-            })
-        };
-        Events {
-            rx,
-            input_handle,
-            tick_handle,
-        }
-    }
-
-    pub fn next(&self) -> Result<Event<Key>, mpsc::RecvError> {
-        self.rx.recv()
-    }
-}

examples/util/mod.rs

@@ -1,131 +0,0 @@
-#[cfg(feature = "termion")]
-pub mod event;
-
-use rand::distributions::{Distribution, Uniform};
-use rand::rngs::ThreadRng;
-use tui::widgets::ListState;
-
-#[derive(Clone)]
-pub struct RandomSignal {
-    distribution: Uniform<u64>,
-    rng: ThreadRng,
-}
-
-impl RandomSignal {
-    pub fn new(lower: u64, upper: u64) -> RandomSignal {
-        RandomSignal {
-            distribution: Uniform::new(lower, upper),
-            rng: rand::thread_rng(),
-        }
-    }
-}
-
-impl Iterator for RandomSignal {
-    type Item = u64;
-    fn next(&mut self) -> Option<u64> {
-        Some(self.distribution.sample(&mut self.rng))
-    }
-}
-
-#[derive(Clone)]
-pub struct SinSignal {
-    x: f64,
-    interval: f64,
-    period: f64,
-    scale: f64,
-}
-
-impl SinSignal {
-    pub fn new(interval: f64, period: f64, scale: f64) -> SinSignal {
-        SinSignal {
-            x: 0.0,
-            interval,
-            period,
-            scale,
-        }
-    }
-}
-
-impl Iterator for SinSignal {
-    type Item = (f64, f64);
-    fn next(&mut self) -> Option<Self::Item> {
-        let point = (self.x, (self.x * 1.0 / self.period).sin() * self.scale);
-        self.x += self.interval;
-        Some(point)
-    }
-}
-
-pub struct TabsState<'a> {
-    pub titles: Vec<&'a str>,
-    pub index: usize,
-}
-
-impl<'a> TabsState<'a> {
-    pub fn new(titles: Vec<&'a str>) -> TabsState {
-        TabsState { titles, index: 0 }
-    }
-    pub fn next(&mut self) {
-        self.index = (self.index + 1) % self.titles.len();
-    }
-
-    pub fn previous(&mut self) {
-        if self.index > 0 {
-            self.index -= 1;
-        } else {
-            self.index = self.titles.len() - 1;
-        }
-    }
-}
-
-pub struct StatefulList<T> {
-    pub state: ListState,
-    pub items: Vec<T>,
-}
-
-impl<T> StatefulList<T> {
-    pub fn new() -> StatefulList<T> {
-        StatefulList {
-            state: ListState::default(),
-            items: Vec::new(),
-        }
-    }
-
-    pub fn with_items(items: Vec<T>) -> StatefulList<T> {
-        StatefulList {
-            state: ListState::default(),
-            items,
-        }
-    }
-
-    pub fn next(&mut self) {
-        let i = match self.state.selected() {
-            Some(i) => {
-                if i >= self.items.len() - 1 {
-                    0
-                } else {
-                    i + 1
-                }
-            }
-            None => 0,
-        };
-        self.state.select(Some(i));
-    }
-
-    pub fn previous(&mut self) {
-        let i = match self.state.selected() {
-            Some(i) => {
-                if i == 0 {
-                    self.items.len() - 1
-                } else {
-                    i - 1
-                }
-            }
-            None => 0,
-        };
-        self.state.select(Some(i));
-    }
-
-    pub fn unselect(&mut self) {
-        self.state.select(None);
-    }
-}

src/backend/crossterm.rs

@@ -1,5 +1,5 @@
 use crate::{
-    backend::Backend,
+    backend::{Backend, ClearType},
     buffer::Cell,
     layout::Rect,
     style::{Color, Modifier},
@@ -11,7 +11,7 @@ use crossterm::{
         Attribute as CAttribute, Color as CColor, Print, SetAttribute, SetBackgroundColor,
         SetForegroundColor,
     },
-    terminal::{self, Clear, ClearType},
+    terminal::{self, Clear},
 };
 use std::io::{self, Write};
 
@@ -56,7 +56,7 @@ where
         for (x, y, cell) in content {
             // Move the cursor if the previous location was not (x - 1, y)
             if !matches!(last_pos, Some(p) if x == p.0 + 1 && y == p.1) {
-                map_error(queue!(self.buffer, MoveTo(x, y)))?;
+                queue!(self.buffer, MoveTo(x, y))?;
             }
             last_pos = Some((x, y));
             if cell.modifier != modifier {
@@ -69,45 +69,60 @@ where
             }
             if cell.fg != fg {
                 let color = CColor::from(cell.fg);
-                map_error(queue!(self.buffer, SetForegroundColor(color)))?;
+                queue!(self.buffer, SetForegroundColor(color))?;
                 fg = cell.fg;
             }
             if cell.bg != bg {
                 let color = CColor::from(cell.bg);
-                map_error(queue!(self.buffer, SetBackgroundColor(color)))?;
+                queue!(self.buffer, SetBackgroundColor(color))?;
                 bg = cell.bg;
             }
 
-            map_error(queue!(self.buffer, Print(&cell.symbol)))?;
+            queue!(self.buffer, Print(&cell.symbol))?;
         }
 
-        map_error(queue!(
+        queue!(
             self.buffer,
             SetForegroundColor(CColor::Reset),
             SetBackgroundColor(CColor::Reset),
             SetAttribute(CAttribute::Reset)
-        ))
+        )
     }
 
     fn hide_cursor(&mut self) -> io::Result<()> {
-        map_error(execute!(self.buffer, Hide))
+        execute!(self.buffer, Hide)
     }
 
     fn show_cursor(&mut self) -> io::Result<()> {
-        map_error(execute!(self.buffer, Show))
+        execute!(self.buffer, Show)
     }
 
     fn get_cursor(&mut self) -> io::Result<(u16, u16)> {
         crossterm::cursor::position()
-            .map_err(|e| io::Error::new(io::ErrorKind::Other, e.to_string()))
     }
 
     fn set_cursor(&mut self, x: u16, y: u16) -> io::Result<()> {
-        map_error(execute!(self.buffer, MoveTo(x, y)))
+        execute!(self.buffer, MoveTo(x, y))
     }
 
-    fn clear(&mut self) -> io::Result<()> {
-        map_error(execute!(self.buffer, Clear(ClearType::All)))
+    fn clear(&mut self, clear_type: ClearType) -> io::Result<()> {
+        execute!(
+            self.buffer,
+            Clear(match clear_type {
+                ClearType::All => crossterm::terminal::ClearType::All,
+                ClearType::AfterCursor => crossterm::terminal::ClearType::FromCursorDown,
+                ClearType::BeforeCursor => crossterm::terminal::ClearType::FromCursorUp,
+                ClearType::CurrentLine => crossterm::terminal::ClearType::CurrentLine,
+                ClearType::UntilNewLine => crossterm::terminal::ClearType::UntilNewLine,
+            })
+        )
+    }
+
+    fn append_lines(&mut self, n: u16) -> io::Result<()> {
+        for _ in 0..n {
+            queue!(self.buffer, Print("\n"))?;
+        }
+        self.buffer.flush()
     }
 
     fn size(&self) -> io::Result<Rect> {
@@ -122,10 +137,6 @@ where
     }
 }
 
-fn map_error(error: crossterm::Result<()>) -> io::Result<()> {
-    error.map_err(|e| io::Error::new(io::ErrorKind::Other, e.to_string()))
-}
-
 impl From<Color> for CColor {
     fn from(color: Color) -> Self {
         match color {
@@ -166,54 +177,54 @@ impl ModifierDiff {
         //use crossterm::Attribute;
         let removed = self.from - self.to;
         if removed.contains(Modifier::REVERSED) {
-            map_error(queue!(w, SetAttribute(CAttribute::NoReverse)))?;
+            queue!(w, SetAttribute(CAttribute::NoReverse))?;
         }
         if removed.contains(Modifier::BOLD) {
-            map_error(queue!(w, SetAttribute(CAttribute::NormalIntensity)))?;
+            queue!(w, SetAttribute(CAttribute::NormalIntensity))?;
             if self.to.contains(Modifier::DIM) {
-                map_error(queue!(w, SetAttribute(CAttribute::Dim)))?;
+                queue!(w, SetAttribute(CAttribute::Dim))?;
             }
         }
         if removed.contains(Modifier::ITALIC) {
-            map_error(queue!(w, SetAttribute(CAttribute::NoItalic)))?;
+            queue!(w, SetAttribute(CAttribute::NoItalic))?;
         }
         if removed.contains(Modifier::UNDERLINED) {
-            map_error(queue!(w, SetAttribute(CAttribute::NoUnderline)))?;
+            queue!(w, SetAttribute(CAttribute::NoUnderline))?;
         }
         if removed.contains(Modifier::DIM) {
-            map_error(queue!(w, SetAttribute(CAttribute::NormalIntensity)))?;
+            queue!(w, SetAttribute(CAttribute::NormalIntensity))?;
         }
         if removed.contains(Modifier::CROSSED_OUT) {
-            map_error(queue!(w, SetAttribute(CAttribute::NotCrossedOut)))?;
+            queue!(w, SetAttribute(CAttribute::NotCrossedOut))?;
         }
         if removed.contains(Modifier::SLOW_BLINK) || removed.contains(Modifier::RAPID_BLINK) {
-            map_error(queue!(w, SetAttribute(CAttribute::NoBlink)))?;
+            queue!(w, SetAttribute(CAttribute::NoBlink))?;
         }
 
         let added = self.to - self.from;
         if added.contains(Modifier::REVERSED) {
-            map_error(queue!(w, SetAttribute(CAttribute::Reverse)))?;
+            queue!(w, SetAttribute(CAttribute::Reverse))?;
         }
         if added.contains(Modifier::BOLD) {
-            map_error(queue!(w, SetAttribute(CAttribute::Bold)))?;
+            queue!(w, SetAttribute(CAttribute::Bold))?;
         }
         if added.contains(Modifier::ITALIC) {
-            map_error(queue!(w, SetAttribute(CAttribute::Italic)))?;
+            queue!(w, SetAttribute(CAttribute::Italic))?;
         }
         if added.contains(Modifier::UNDERLINED) {
-            map_error(queue!(w, SetAttribute(CAttribute::Underlined)))?;
+            queue!(w, SetAttribute(CAttribute::Underlined))?;
         }
         if added.contains(Modifier::DIM) {
-            map_error(queue!(w, SetAttribute(CAttribute::Dim)))?;
+            queue!(w, SetAttribute(CAttribute::Dim))?;
         }
         if added.contains(Modifier::CROSSED_OUT) {
-            map_error(queue!(w, SetAttribute(CAttribute::CrossedOut)))?;
+            queue!(w, SetAttribute(CAttribute::CrossedOut))?;
         }
         if added.contains(Modifier::SLOW_BLINK) {
-            map_error(queue!(w, SetAttribute(CAttribute::SlowBlink)))?;
+            queue!(w, SetAttribute(CAttribute::SlowBlink))?;
         }
         if added.contains(Modifier::RAPID_BLINK) {
-            map_error(queue!(w, SetAttribute(CAttribute::RapidBlink)))?;
+            queue!(w, SetAttribute(CAttribute::RapidBlink))?;
         }
 
         Ok(())

src/backend/curses.rs

@@ -1,280 +0,0 @@
-use std::io;
-
-use crate::backend::Backend;
-use crate::buffer::Cell;
-use crate::layout::Rect;
-use crate::style::{Color, Modifier};
-use crate::symbols::{bar, block};
-#[cfg(unix)]
-use crate::symbols::{line, DOT};
-#[cfg(unix)]
-use pancurses::{chtype, ToChtype};
-use unicode_segmentation::UnicodeSegmentation;
-
-pub struct CursesBackend {
-    curses: easycurses::EasyCurses,
-}
-
-impl CursesBackend {
-    pub fn new() -> Option<CursesBackend> {
-        let curses = easycurses::EasyCurses::initialize_system()?;
-        Some(CursesBackend { curses })
-    }
-
-    pub fn with_curses(curses: easycurses::EasyCurses) -> CursesBackend {
-        CursesBackend { curses }
-    }
-
-    pub fn get_curses(&self) -> &easycurses::EasyCurses {
-        &self.curses
-    }
-
-    pub fn get_curses_mut(&mut self) -> &mut easycurses::EasyCurses {
-        &mut self.curses
-    }
-}
-
-impl Backend for CursesBackend {
-    fn draw<'a, I>(&mut self, content: I) -> io::Result<()>
-    where
-        I: Iterator<Item = (u16, u16, &'a Cell)>,
-    {
-        let mut last_col = 0;
-        let mut last_row = 0;
-        let mut fg = Color::Reset;
-        let mut bg = Color::Reset;
-        let mut modifier = Modifier::empty();
-        let mut curses_style = CursesStyle {
-            fg: easycurses::Color::White,
-            bg: easycurses::Color::Black,
-        };
-        let mut update_color = false;
-        for (col, row, cell) in content {
-            if row != last_row || col != last_col + 1 {
-                self.curses.move_rc(i32::from(row), i32::from(col));
-            }
-            last_col = col;
-            last_row = row;
-            if cell.modifier != modifier {
-                apply_modifier_diff(&mut self.curses.win, modifier, cell.modifier);
-                modifier = cell.modifier;
-            };
-            if cell.fg != fg {
-                update_color = true;
-                if let Some(ccolor) = cell.fg.into() {
-                    fg = cell.fg;
-                    curses_style.fg = ccolor;
-                } else {
-                    fg = Color::White;
-                    curses_style.fg = easycurses::Color::White;
-                }
-            };
-            if cell.bg != bg {
-                update_color = true;
-                if let Some(ccolor) = cell.bg.into() {
-                    bg = cell.bg;
-                    curses_style.bg = ccolor;
-                } else {
-                    bg = Color::Black;
-                    curses_style.bg = easycurses::Color::Black;
-                }
-            };
-            if update_color {
-                self.curses
-                    .set_color_pair(easycurses::ColorPair::new(curses_style.fg, curses_style.bg));
-            };
-            update_color = false;
-            draw(&mut self.curses, cell.symbol.as_str());
-        }
-        self.curses.win.attrset(pancurses::Attribute::Normal);
-        self.curses.set_color_pair(easycurses::ColorPair::new(
-            easycurses::Color::White,
-            easycurses::Color::Black,
-        ));
-        Ok(())
-    }
-    fn hide_cursor(&mut self) -> io::Result<()> {
-        self.curses
-            .set_cursor_visibility(easycurses::CursorVisibility::Invisible);
-        Ok(())
-    }
-    fn show_cursor(&mut self) -> io::Result<()> {
-        self.curses
-            .set_cursor_visibility(easycurses::CursorVisibility::Visible);
-        Ok(())
-    }
-    fn get_cursor(&mut self) -> io::Result<(u16, u16)> {
-        let (y, x) = self.curses.get_cursor_rc();
-        Ok((x as u16, y as u16))
-    }
-    fn set_cursor(&mut self, x: u16, y: u16) -> io::Result<()> {
-        self.curses.move_rc(i32::from(y), i32::from(x));
-        Ok(())
-    }
-    fn clear(&mut self) -> io::Result<()> {
-        self.curses.clear();
-        // self.curses.refresh();
-        Ok(())
-    }
-    fn size(&self) -> Result<Rect, io::Error> {
-        let (nrows, ncols) = self.curses.get_row_col_count();
-        Ok(Rect::new(0, 0, ncols as u16, nrows as u16))
-    }
-    fn flush(&mut self) -> io::Result<()> {
-        self.curses.refresh();
-        Ok(())
-    }
-}
-
-struct CursesStyle {
-    fg: easycurses::Color,
-    bg: easycurses::Color,
-}
-
-#[cfg(unix)]
-/// Deals with lack of unicode support for ncurses on unix
-fn draw(curses: &mut easycurses::EasyCurses, symbol: &str) {
-    for grapheme in symbol.graphemes(true) {
-        let ch = match grapheme {
-            line::TOP_RIGHT => pancurses::ACS_URCORNER(),
-            line::VERTICAL => pancurses::ACS_VLINE(),
-            line::HORIZONTAL => pancurses::ACS_HLINE(),
-            line::TOP_LEFT => pancurses::ACS_ULCORNER(),
-            line::BOTTOM_RIGHT => pancurses::ACS_LRCORNER(),
-            line::BOTTOM_LEFT => pancurses::ACS_LLCORNER(),
-            line::VERTICAL_LEFT => pancurses::ACS_RTEE(),
-            line::VERTICAL_RIGHT => pancurses::ACS_LTEE(),
-            line::HORIZONTAL_DOWN => pancurses::ACS_TTEE(),
-            line::HORIZONTAL_UP => pancurses::ACS_BTEE(),
-            block::FULL => pancurses::ACS_BLOCK(),
-            block::SEVEN_EIGHTHS => pancurses::ACS_BLOCK(),
-            block::THREE_QUARTERS => pancurses::ACS_BLOCK(),
-            block::FIVE_EIGHTHS => pancurses::ACS_BLOCK(),
-            block::HALF => pancurses::ACS_BLOCK(),
-            block::THREE_EIGHTHS => ' ' as chtype,
-            block::ONE_QUARTER => ' ' as chtype,
-            block::ONE_EIGHTH => ' ' as chtype,
-            bar::SEVEN_EIGHTHS => pancurses::ACS_BLOCK(),
-            bar::THREE_QUARTERS => pancurses::ACS_BLOCK(),
-            bar::FIVE_EIGHTHS => pancurses::ACS_BLOCK(),
-            bar::HALF => pancurses::ACS_BLOCK(),
-            bar::THREE_EIGHTHS => pancurses::ACS_S9(),
-            bar::ONE_QUARTER => pancurses::ACS_S9(),
-            bar::ONE_EIGHTH => pancurses::ACS_S9(),
-            DOT => pancurses::ACS_BULLET(),
-            unicode_char => {
-                if unicode_char.is_ascii() {
-                    let mut chars = unicode_char.chars();
-                    if let Some(ch) = chars.next() {
-                        ch.to_chtype()
-                    } else {
-                        pancurses::ACS_BLOCK()
-                    }
-                } else {
-                    pancurses::ACS_BLOCK()
-                }
-            }
-        };
-        curses.win.addch(ch);
-    }
-}
-
-#[cfg(windows)]
-fn draw(curses: &mut easycurses::EasyCurses, symbol: &str) {
-    for grapheme in symbol.graphemes(true) {
-        let ch = match grapheme {
-            block::SEVEN_EIGHTHS => block::FULL,
-            block::THREE_QUARTERS => block::FULL,
-            block::FIVE_EIGHTHS => block::HALF,
-            block::THREE_EIGHTHS => block::HALF,
-            block::ONE_QUARTER => block::HALF,
-            block::ONE_EIGHTH => " ",
-            bar::SEVEN_EIGHTHS => bar::FULL,
-            bar::THREE_QUARTERS => bar::FULL,
-            bar::FIVE_EIGHTHS => bar::HALF,
-            bar::THREE_EIGHTHS => bar::HALF,
-            bar::ONE_QUARTER => bar::HALF,
-            bar::ONE_EIGHTH => " ",
-            ch => ch,
-        };
-        // curses.win.addch(ch);
-        curses.print(ch);
-    }
-}
-
-impl From<Color> for Option<easycurses::Color> {
-    fn from(color: Color) -> Option<easycurses::Color> {
-        match color {
-            Color::Reset => None,
-            Color::Black => Some(easycurses::Color::Black),
-            Color::Red | Color::LightRed => Some(easycurses::Color::Red),
-            Color::Green | Color::LightGreen => Some(easycurses::Color::Green),
-            Color::Yellow | Color::LightYellow => Some(easycurses::Color::Yellow),
-            Color::Magenta | Color::LightMagenta => Some(easycurses::Color::Magenta),
-            Color::Cyan | Color::LightCyan => Some(easycurses::Color::Cyan),
-            Color::White | Color::Gray | Color::DarkGray => Some(easycurses::Color::White),
-            Color::Blue | Color::LightBlue => Some(easycurses::Color::Blue),
-            Color::Indexed(_) => None,
-            Color::Rgb(_, _, _) => None,
-        }
-    }
-}
-
-fn apply_modifier_diff(win: &mut pancurses::Window, from: Modifier, to: Modifier) {
-    remove_modifier(win, from - to);
-    add_modifier(win, to - from);
-}
-
-fn remove_modifier(win: &mut pancurses::Window, remove: Modifier) {
-    if remove.contains(Modifier::BOLD) {
-        win.attroff(pancurses::Attribute::Bold);
-    }
-    if remove.contains(Modifier::DIM) {
-        win.attroff(pancurses::Attribute::Dim);
-    }
-    if remove.contains(Modifier::ITALIC) {
-        win.attroff(pancurses::Attribute::Italic);
-    }
-    if remove.contains(Modifier::UNDERLINED) {
-        win.attroff(pancurses::Attribute::Underline);
-    }
-    if remove.contains(Modifier::SLOW_BLINK) || remove.contains(Modifier::RAPID_BLINK) {
-        win.attroff(pancurses::Attribute::Blink);
-    }
-    if remove.contains(Modifier::REVERSED) {
-        win.attroff(pancurses::Attribute::Reverse);
-    }
-    if remove.contains(Modifier::HIDDEN) {
-        win.attroff(pancurses::Attribute::Invisible);
-    }
-    if remove.contains(Modifier::CROSSED_OUT) {
-        win.attroff(pancurses::Attribute::Strikeout);
-    }
-}
-
-fn add_modifier(win: &mut pancurses::Window, add: Modifier) {
-    if add.contains(Modifier::BOLD) {
-        win.attron(pancurses::Attribute::Bold);
-    }
-    if add.contains(Modifier::DIM) {
-        win.attron(pancurses::Attribute::Dim);
-    }
-    if add.contains(Modifier::ITALIC) {
-        win.attron(pancurses::Attribute::Italic);
-    }
-    if add.contains(Modifier::UNDERLINED) {
-        win.attron(pancurses::Attribute::Underline);
-    }
-    if add.contains(Modifier::SLOW_BLINK) || add.contains(Modifier::RAPID_BLINK) {
-        win.attron(pancurses::Attribute::Blink);
-    }
-    if add.contains(Modifier::REVERSED) {
-        win.attron(pancurses::Attribute::Reverse);
-    }
-    if add.contains(Modifier::HIDDEN) {
-        win.attron(pancurses::Attribute::Invisible);
-    }
-    if add.contains(Modifier::CROSSED_OUT) {
-        win.attron(pancurses::Attribute::Strikeout);
-    }
-}

src/backend/mod.rs

@@ -3,11 +3,6 @@ use std::io;
 use crate::buffer::Cell;
 use crate::layout::Rect;
 
-#[cfg(feature = "rustbox")]
-mod rustbox;
-#[cfg(feature = "rustbox")]
-pub use self::rustbox::RustboxBackend;
-
 #[cfg(feature = "termion")]
 mod termion;
 #[cfg(feature = "termion")]
@@ -18,23 +13,28 @@ mod crossterm;
 #[cfg(feature = "crossterm")]
 pub use self::crossterm::CrosstermBackend;
 
-#[cfg(feature = "curses")]
-mod curses;
-#[cfg(feature = "curses")]
-pub use self::curses::CursesBackend;
-
 mod test;
 pub use self::test::TestBackend;
 
+#[derive(Debug, Clone, Copy, PartialEq)]
+pub enum ClearType {
+    All,
+    AfterCursor,
+    BeforeCursor,
+    CurrentLine,
+    UntilNewLine,
+}
+
 pub trait Backend {
     fn draw<'a, I>(&mut self, content: I) -> Result<(), io::Error>
     where
         I: Iterator<Item = (u16, u16, &'a Cell)>;
+    fn append_lines(&mut self, n: u16) -> io::Result<()>;
     fn hide_cursor(&mut self) -> Result<(), io::Error>;
     fn show_cursor(&mut self) -> Result<(), io::Error>;
     fn get_cursor(&mut self) -> Result<(u16, u16), io::Error>;
     fn set_cursor(&mut self, x: u16, y: u16) -> Result<(), io::Error>;
-    fn clear(&mut self) -> Result<(), io::Error>;
+    fn clear(&mut self, clear_type: ClearType) -> Result<(), io::Error>;
     fn size(&self) -> Result<Rect, io::Error>;
     fn flush(&mut self) -> Result<(), io::Error>;
 }

src/backend/rustbox.rs

@@ -1,123 +0,0 @@
-use crate::{
-    backend::Backend,
-    buffer::Cell,
-    layout::Rect,
-    style::{Color, Modifier},
-};
-use std::io;
-
-pub struct RustboxBackend {
-    rustbox: rustbox::RustBox,
-}
-
-impl RustboxBackend {
-    pub fn new() -> Result<RustboxBackend, rustbox::InitError> {
-        let rustbox = rustbox::RustBox::init(Default::default())?;
-        Ok(RustboxBackend { rustbox })
-    }
-
-    pub fn with_rustbox(instance: rustbox::RustBox) -> RustboxBackend {
-        RustboxBackend { rustbox: instance }
-    }
-
-    pub fn rustbox(&self) -> &rustbox::RustBox {
-        &self.rustbox
-    }
-}
-
-impl Backend for RustboxBackend {
-    fn draw<'a, I>(&mut self, content: I) -> Result<(), io::Error>
-    where
-        I: Iterator<Item = (u16, u16, &'a Cell)>,
-    {
-        for (x, y, cell) in content {
-            self.rustbox.print(
-                x as usize,
-                y as usize,
-                cell.modifier.into(),
-                cell.fg.into(),
-                cell.bg.into(),
-                &cell.symbol,
-            );
-        }
-        Ok(())
-    }
-    fn hide_cursor(&mut self) -> Result<(), io::Error> {
-        Ok(())
-    }
-    fn show_cursor(&mut self) -> Result<(), io::Error> {
-        Ok(())
-    }
-    fn get_cursor(&mut self) -> io::Result<(u16, u16)> {
-        Err(io::Error::from(io::ErrorKind::Other))
-    }
-    fn set_cursor(&mut self, x: u16, y: u16) -> io::Result<()> {
-        self.rustbox.set_cursor(x as isize, y as isize);
-        Ok(())
-    }
-    fn clear(&mut self) -> Result<(), io::Error> {
-        self.rustbox.clear();
-        Ok(())
-    }
-    fn size(&self) -> Result<Rect, io::Error> {
-        let term_width = self.rustbox.width();
-        let term_height = self.rustbox.height();
-        let max = u16::max_value();
-        Ok(Rect::new(
-            0,
-            0,
-            if term_width > usize::from(max) {
-                max
-            } else {
-                term_width as u16
-            },
-            if term_height > usize::from(max) {
-                max
-            } else {
-                term_height as u16
-            },
-        ))
-    }
-    fn flush(&mut self) -> Result<(), io::Error> {
-        self.rustbox.present();
-        Ok(())
-    }
-}
-
-fn rgb_to_byte(r: u8, g: u8, b: u8) -> u16 {
-    u16::from((r & 0xC0) + ((g & 0xE0) >> 2) + ((b & 0xE0) >> 5))
-}
-
-impl From<Color> for rustbox::Color {
-    fn from(color: Color) -> rustbox::Color {
-        match color {
-            Color::Reset => rustbox::Color::Default,
-            Color::Black | Color::Gray | Color::DarkGray => rustbox::Color::Black,
-            Color::Red | Color::LightRed => rustbox::Color::Red,
-            Color::Green | Color::LightGreen => rustbox::Color::Green,
-            Color::Yellow | Color::LightYellow => rustbox::Color::Yellow,
-            Color::Magenta | Color::LightMagenta => rustbox::Color::Magenta,
-            Color::Cyan | Color::LightCyan => rustbox::Color::Cyan,
-            Color::White => rustbox::Color::White,
-            Color::Blue | Color::LightBlue => rustbox::Color::Blue,
-            Color::Indexed(i) => rustbox::Color::Byte(u16::from(i)),
-            Color::Rgb(r, g, b) => rustbox::Color::Byte(rgb_to_byte(r, g, b)),
-        }
-    }
-}
-
-impl From<Modifier> for rustbox::Style {
-    fn from(modifier: Modifier) -> rustbox::Style {
-        let mut result = rustbox::Style::empty();
-        if modifier.contains(Modifier::BOLD) {
-            result.insert(rustbox::RB_BOLD);
-        }
-        if modifier.contains(Modifier::UNDERLINED) {
-            result.insert(rustbox::RB_UNDERLINE);
-        }
-        if modifier.contains(Modifier::REVERSED) {
-            result.insert(rustbox::RB_REVERSE);
-        }
-        result
-    }
-}

src/backend/termion.rs

@@ -1,5 +1,5 @@
-use super::Backend;
 use crate::{
+    backend::{Backend, ClearType},
     buffer::Cell,
     layout::Rect,
     style::{Color, Modifier},
@@ -42,10 +42,21 @@ impl<W> Backend for TermionBackend<W>
 where
     W: Write,
 {
-    /// Clears the entire screen and move the cursor to the top left of the screen
-    fn clear(&mut self) -> io::Result<()> {
-        write!(self.stdout, "{}", termion::clear::All)?;
-        write!(self.stdout, "{}", termion::cursor::Goto(1, 1))?;
+    fn clear(&mut self, clear_type: ClearType) -> io::Result<()> {
+        match clear_type {
+            ClearType::All => write!(self.stdout, "{}", termion::clear::All)?,
+            ClearType::AfterCursor => write!(self.stdout, "{}", termion::clear::AfterCursor)?,
+            ClearType::BeforeCursor => write!(self.stdout, "{}", termion::clear::BeforeCursor)?,
+            ClearType::CurrentLine => write!(self.stdout, "{}", termion::clear::CurrentLine)?,
+            ClearType::UntilNewLine => write!(self.stdout, "{}", termion::clear::UntilNewline)?,
+        };
+        self.stdout.flush()
+    }
+
+    fn append_lines(&mut self, n: u16) -> io::Result<()> {
+        for _ in 0..n {
+            writeln!(self.stdout)?;
+        }
         self.stdout.flush()
     }
 

src/backend/test.rs

@@ -1,5 +1,5 @@
 use crate::{
-    backend::Backend,
+    backend::{Backend, ClearType},
     buffer::{Buffer, Cell},
     layout::Rect,
 };
@@ -117,6 +117,10 @@ impl Backend for TestBackend {
         Ok(())
     }
 
+    fn append_lines(&mut self, _n: u16) -> Result<(), io::Error> {
+        Ok(())
+    }
+
     fn hide_cursor(&mut self) -> Result<(), io::Error> {
         self.cursor = false;
         Ok(())
@@ -136,7 +140,7 @@ impl Backend for TestBackend {
         Ok(())
     }
 
-    fn clear(&mut self) -> Result<(), io::Error> {
+    fn clear(&mut self, _clear_type: ClearType) -> Result<(), io::Error> {
         self.buffer.reset();
         Ok(())
     }

src/buffer.rs

@@ -105,7 +105,7 @@ impl Default for Cell {
 /// buf.get_mut(5, 0).set_char('x');
 /// assert_eq!(buf.get(5, 0).symbol, "x");
 /// ```
-#[derive(Debug, Clone, PartialEq)]
+#[derive(Debug, Clone, PartialEq, Default)]
 pub struct Buffer {
     /// The area represented by this buffer
     pub area: Rect,
@@ -114,15 +114,6 @@ pub struct Buffer {
     pub content: Vec<Cell>,
 }
 
-impl Default for Buffer {
-    fn default() -> Buffer {
-        Buffer {
-            area: Default::default(),
-            content: Vec::new(),
-        }
-    }
-}
-
 impl Buffer {
     /// Returns a Buffer with all cells set to the default one
     pub fn empty(area: Rect) -> Buffer {
@@ -440,7 +431,6 @@ impl Buffer {
     pub fn diff<'a>(&self, other: &'a Buffer) -> Vec<(u16, u16, &'a Cell)> {
         let previous_buffer = &self.content;
         let next_buffer = &other.content;
-        let width = self.area.width;
 
         let mut updates: Vec<(u16, u16, &Cell)> = vec![];
         // Cells invalidated by drawing/replacing preceeding multi-width characters:
@@ -450,8 +440,7 @@ impl Buffer {
         let mut to_skip: usize = 0;
         for (i, (current, previous)) in next_buffer.iter().zip(previous_buffer.iter()).enumerate() {
             if (current != previous || invalidated > 0) && to_skip == 0 {
-                let x = i as u16 % width;
-                let y = i as u16 / width;
+                let (x, y) = self.pos_of(i);
                 updates.push((x, y, &next_buffer[i]));
             }
 

src/layout.rs

@@ -363,7 +363,7 @@ impl Element {
 
 /// A simple rectangle used in the computation of the layout and to give widgets an hint about the
 /// area they are supposed to render to.
-#[derive(Debug, Clone, Copy, Hash, PartialEq, Eq)]
+#[derive(Debug, Clone, Copy, Hash, PartialEq, Eq, Default)]
 pub struct Rect {
     pub x: u16,
     pub y: u16,
@@ -371,17 +371,6 @@ pub struct Rect {
     pub height: u16,
 }
 
-impl Default for Rect {
-    fn default() -> Rect {
-        Rect {
-            x: 0,
-            y: 0,
-            width: 0,
-            height: 0,
-        }
-    }
-}
-
 impl Rect {
     /// Creates a new rect, with width and height limited to keep the area under max u16.
     /// If clipped, aspect ratio will be preserved.

src/lib.rs

@@ -10,17 +10,17 @@
 //! ```toml
 //! [dependencies]
 //! tui = "0.16"
-//! termion = "1.5"
+//! crossterm = "0.22"
 //! ```
 //!
-//! The crate is using the `termion` backend by default but if for example you want your
-//! application to work on Windows, you might want to use the `crossterm` backend instead. This can
-//! be done by changing your dependencies specification to the following:
+//! The crate is using the `crossterm` backend by default that works on most platforms. But if for
+//! example you want to use the `termion` backend instead. This can be done by changing your
+//! dependencies specification to the following:
 //!
 //! ```toml
 //! [dependencies]
-//! crossterm = "0.20"
-//! tui = { version = "0.16", default-features = false, features = ['crossterm'] }
+//! termion = "1.5"
+//! tui = { version = "0.16", default-features = false, features = ['termion'] }
 //! ```
 //!
 //! The same logic applies for all other available backends.
@@ -33,29 +33,27 @@
 //!
 //! ```rust,no_run
 //! use std::io;
-//! use tui::Terminal;
-//! use tui::backend::TermionBackend;
-//! use termion::raw::IntoRawMode;
+//! use tui::{backend::CrosstermBackend, Terminal};
 //!
 //! fn main() -> Result<(), io::Error> {
-//!     let stdout = io::stdout().into_raw_mode()?;
-//!     let backend = TermionBackend::new(stdout);
+//!     let stdout = io::stdout();
+//!     let backend = CrosstermBackend::new(stdout);
 //!     let mut terminal = Terminal::new(backend)?;
 //!     Ok(())
 //! }
 //! ```
 //!
-//! If you had previously chosen `crossterm` as a backend, the terminal can be created in a similar
+//! If you had previously chosen `termion` as a backend, the terminal can be created in a similar
 //! way:
 //!
 //! ```rust,ignore
 //! use std::io;
-//! use tui::Terminal;
-//! use tui::backend::CrosstermBackend;
+//! use tui::{backend::TermionBackend, Terminal};
+//! use termion::raw::IntoRawMode;
 //!
 //! fn main() -> Result<(), io::Error> {
-//!     let stdout = io::stdout();
-//!     let backend = CrosstermBackend::new(stdout);
+//!     let stdout = io::stdout().into_raw_mode()?;
+//!     let backend = TermionBackend::new(stdout);
 //!     let mut terminal = Terminal::new(backend)?;
 //!     Ok(())
 //! }
@@ -77,17 +75,27 @@
 //! The following example renders a block of the size of the terminal:
 //!
 //! ```rust,no_run
-//! use std::io;
-//! use termion::raw::IntoRawMode;
-//! use tui::Terminal;
-//! use tui::backend::TermionBackend;
-//! use tui::widgets::{Widget, Block, Borders};
-//! use tui::layout::{Layout, Constraint, Direction};
+//! use std::{io, thread, time::Duration};
+//! use tui::{
+//!     backend::CrosstermBackend,
+//!     widgets::{Widget, Block, Borders},
+//!     layout::{Layout, Constraint, Direction},
+//!     Terminal
+//! };
+//! use crossterm::{
+//!     event::{self, DisableMouseCapture, EnableMouseCapture, Event, KeyCode},
+//!     execute,
+//!     terminal::{disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen},
+//! };
 //!
 //! fn main() -> Result<(), io::Error> {
-//!     let stdout = io::stdout().into_raw_mode()?;
-//!     let backend = TermionBackend::new(stdout);
+//!     // setup terminal
+//!     enable_raw_mode()?;
+//!     let mut stdout = io::stdout();
+//!     execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
+//!     let backend = CrosstermBackend::new(stdout);
 //!     let mut terminal = Terminal::new(backend)?;
+//!
 //!     terminal.draw(|f| {
 //!         let size = f.size();
 //!         let block = Block::default()
@@ -95,6 +103,18 @@
 //!             .borders(Borders::ALL);
 //!         f.render_widget(block, size);
 //!     })?;
+//!
+//!     thread::sleep(Duration::from_millis(5000));
+//!
+//!     // restore terminal
+//!     disable_raw_mode()?;
+//!     execute!(
+//!         terminal.backend_mut(),
+//!         LeaveAlternateScreen,
+//!         DisableMouseCapture
+//!     )?;
+//!     terminal.show_cursor()?;
+//!
 //!     Ok(())
 //! }
 //! ```
@@ -106,39 +126,32 @@
 //! full customization. And `Layout` is no exception:
 //!
 //! ```rust,no_run
-//! use std::io;
-//! use termion::raw::IntoRawMode;
-//! use tui::Terminal;
-//! use tui::backend::TermionBackend;
-//! use tui::widgets::{Widget, Block, Borders};
-//! use tui::layout::{Layout, Constraint, Direction};
-//!
-//! fn main() -> Result<(), io::Error> {
-//!     let stdout = io::stdout().into_raw_mode()?;
-//!     let backend = TermionBackend::new(stdout);
-//!     let mut terminal = Terminal::new(backend)?;
-//!     terminal.draw(|f| {
-//!         let chunks = Layout::default()
-//!             .direction(Direction::Vertical)
-//!             .margin(1)
-//!             .constraints(
-//!                 [
-//!                     Constraint::Percentage(10),
-//!                     Constraint::Percentage(80),
-//!                     Constraint::Percentage(10)
-//!                 ].as_ref()
-//!             )
-//!             .split(f.size());
-//!         let block = Block::default()
-//!              .title("Block")
-//!              .borders(Borders::ALL);
-//!         f.render_widget(block, chunks[0]);
-//!         let block = Block::default()
-//!              .title("Block 2")
-//!              .borders(Borders::ALL);
-//!         f.render_widget(block, chunks[1]);
-//!     })?;
-//!     Ok(())
+//! use tui::{
+//!     backend::Backend,
+//!     layout::{Constraint, Direction, Layout},
+//!     widgets::{Block, Borders},
+//!     Frame,
+//! };
+//! fn ui<B: Backend>(f: &mut Frame<B>) {
+//!    let chunks = Layout::default()
+//!         .direction(Direction::Vertical)
+//!         .margin(1)
+//!         .constraints(
+//!             [
+//!                 Constraint::Percentage(10),
+//!                 Constraint::Percentage(80),
+//!                 Constraint::Percentage(10)
+//!             ].as_ref()
+//!         )
+//!         .split(f.size());
+//!     let block = Block::default()
+//!          .title("Block")
+//!          .borders(Borders::ALL);
+//!     f.render_widget(block, chunks[0]);
+//!     let block = Block::default()
+//!          .title("Block 2")
+//!          .borders(Borders::ALL);
+//!     f.render_widget(block, chunks[1]);
 //! }
 //! ```
 //!
@@ -156,4 +169,4 @@ pub mod terminal;
 pub mod text;
 pub mod widgets;
 
-pub use self::terminal::{Frame, Terminal, TerminalOptions, Viewport};
+pub use self::terminal::{Frame, Terminal, TerminalOptions, ViewportVariant};

src/terminal.rs

@@ -1,40 +1,30 @@
 use crate::{
-    backend::Backend,
+    backend::{Backend, ClearType},
     buffer::Buffer,
     layout::Rect,
     widgets::{StatefulWidget, Widget},
 };
 use std::io;
+use tracing::{event, span, Level};
 
 #[derive(Debug, Clone, PartialEq)]
-/// UNSTABLE
-enum ResizeBehavior {
-    Fixed,
-    Auto,
-}
-
-#[derive(Debug, Clone, PartialEq)]
-/// UNSTABLE
-pub struct Viewport {
-    area: Rect,
-    resize_behavior: ResizeBehavior,
-}
-
-impl Viewport {
-    /// UNSTABLE
-    pub fn fixed(area: Rect) -> Viewport {
-        Viewport {
-            area,
-            resize_behavior: ResizeBehavior::Fixed,
-        }
-    }
+pub enum ViewportVariant {
+    Fullscreen,
+    Inline(u16),
+    Fixed(Rect),
 }
 
 #[derive(Debug, Clone, PartialEq)]
 /// Options to pass to [`Terminal::with_options`]
 pub struct TerminalOptions {
     /// Viewport used to draw to the terminal
-    pub viewport: Viewport,
+    pub viewport: ViewportVariant,
+}
+
+#[derive(Debug, Clone, PartialEq)]
+struct Viewport {
+    variant: ViewportVariant,
+    area: Rect,
 }
 
 /// Interface to the terminal backed by Termion
@@ -53,6 +43,11 @@ where
     hidden_cursor: bool,
     /// Viewport
     viewport: Viewport,
+    /// Last known size of the terminal. Used to detect if the internal buffers have to be resized.
+    last_known_size: Rect,
+    /// Last known position of the cursor. Used to find the new area when the viewport is inlined
+    /// and the terminal resized.
+    last_known_cursor_pos: (u16, u16),
 }
 
 /// Represents a consistent terminal interface for rendering.
@@ -73,7 +68,7 @@ impl<'a, B> Frame<'a, B>
 where
     B: Backend,
 {
-    /// Terminal size, guaranteed not to change when rendering.
+    /// Frame size, guaranteed not to change when rendering.
     pub fn size(&self) -> Rect {
         self.terminal.viewport.area
     }
@@ -82,14 +77,12 @@ where
     ///
     /// # Examples
     ///
-    /// ```rust,no_run
-    /// # use std::io;
+    /// ```rust
     /// # use tui::Terminal;
-    /// # use tui::backend::TermionBackend;
+    /// # use tui::backend::TestBackend;
     /// # use tui::layout::Rect;
     /// # use tui::widgets::Block;
-    /// # let stdout = io::stdout();
-    /// # let backend = TermionBackend::new(stdout);
+    /// # let backend = TestBackend::new(5, 5);
     /// # let mut terminal = Terminal::new(backend).unwrap();
     /// let block = Block::default();
     /// let area = Rect::new(0, 0, 5, 5);
@@ -110,14 +103,12 @@ where
     ///
     /// # Examples
     ///
-    /// ```rust,no_run
-    /// # use std::io;
+    /// ```rust
     /// # use tui::Terminal;
-    /// # use tui::backend::TermionBackend;
+    /// # use tui::backend::TestBackend;
     /// # use tui::layout::Rect;
     /// # use tui::widgets::{List, ListItem, ListState};
-    /// # let stdout = io::stdout();
-    /// # let backend = TermionBackend::new(stdout);
+    /// # let backend = TestBackend::new(5, 5);
     /// # let mut terminal = Terminal::new(backend).unwrap();
     /// let mut state = ListState::default();
     /// state.select(Some(1));
@@ -177,29 +168,50 @@ where
     /// Wrapper around Terminal initialization. Each buffer is initialized with a blank string and
     /// default colors for the foreground and the background
     pub fn new(backend: B) -> io::Result<Terminal<B>> {
-        let size = backend.size()?;
         Terminal::with_options(
             backend,
             TerminalOptions {
-                viewport: Viewport {
-                    area: size,
-                    resize_behavior: ResizeBehavior::Auto,
-                },
+                viewport: ViewportVariant::Fullscreen,
             },
         )
     }
 
-    /// UNSTABLE
-    pub fn with_options(backend: B, options: TerminalOptions) -> io::Result<Terminal<B>> {
+    pub fn with_options(mut backend: B, options: TerminalOptions) -> io::Result<Terminal<B>> {
+        let size = backend.size()?;
+        let (viewport_area, cursor_pos) = match options.viewport {
+            ViewportVariant::Fullscreen => (size, (0, 0)),
+            ViewportVariant::Inline(height) => {
+                let pos = backend.get_cursor()?;
+                let mut row = pos.1;
+                let max_height = size.height.min(height);
+                backend.append_lines(max_height.saturating_sub(1))?;
+                let missing_lines = row.saturating_add(max_height).saturating_sub(size.height);
+                if missing_lines > 0 {
+                    row = row.saturating_sub(missing_lines);
+                }
+                (
+                    Rect {
+                        x: 0,
+                        y: row,
+                        width: size.width,
+                        height: max_height,
+                    },
+                    pos,
+                )
+            }
+            ViewportVariant::Fixed(area) => (area, (area.left(), area.top())),
+        };
         Ok(Terminal {
             backend,
-            buffers: [
-                Buffer::empty(options.viewport.area),
-                Buffer::empty(options.viewport.area),
-            ],
+            buffers: [Buffer::empty(viewport_area), Buffer::empty(viewport_area)],
             current: 0,
             hidden_cursor: false,
-            viewport: options.viewport,
+            viewport: Viewport {
+                variant: options.viewport,
+                area: viewport_area,
+            },
+            last_known_size: size,
+            last_known_cursor_pos: cursor_pos,
         })
     }
 
@@ -229,28 +241,61 @@ where
         let previous_buffer = &self.buffers[1 - self.current];
         let current_buffer = &self.buffers[self.current];
         let updates = previous_buffer.diff(current_buffer);
+        if let Some((col, row, _)) = updates.last() {
+            self.last_known_cursor_pos = (*col, *row);
+        }
         self.backend.draw(updates.into_iter())
     }
 
-    /// Updates the Terminal so that internal buffers match the requested size. Requested size will
-    /// be saved so the size can remain consistent when rendering.
-    /// This leads to a full clear of the screen.
-    pub fn resize(&mut self, area: Rect) -> io::Result<()> {
-        self.buffers[self.current].resize(area);
-        self.buffers[1 - self.current].resize(area);
-        self.viewport.area = area;
-        self.clear()
+    /// Queries the backend for size and resizes if it doesn't match the previous size.
+    pub fn resize(&mut self) -> io::Result<()> {
+        let size = self.size()?;
+        if self.last_known_size == size {
+            return Ok(());
+        }
+
+        event!(Level::DEBUG, last_known_size = ?self.last_known_size, ?size, "terminal size changed");
+
+        let next_area = match self.viewport.variant {
+            ViewportVariant::Fullscreen => size,
+            ViewportVariant::Inline(height) => {
+                let (_, mut row) = self.get_cursor()?;
+                let offset_in_previous_viewport = self
+                    .last_known_cursor_pos
+                    .1
+                    .saturating_sub(self.viewport.area.top());
+                let max_height = height.min(size.height);
+                let lines_after_cursor = height
+                    .saturating_sub(offset_in_previous_viewport)
+                    .saturating_sub(1);
+                let available_lines = size.height.saturating_sub(row).saturating_sub(1);
+                let missing_lines = lines_after_cursor.saturating_sub(available_lines);
+                self.backend.append_lines(lines_after_cursor)?;
+                if missing_lines > 0 {
+                    row = row.saturating_sub(missing_lines);
+                }
+                row = row.saturating_sub(offset_in_previous_viewport);
+                Rect {
+                    x: 0,
+                    y: row,
+                    width: size.width,
+                    height: max_height,
+                }
+            }
+            ViewportVariant::Fixed(area) => area,
+        };
+        self.set_viewport_area(next_area);
+        self.clear()?;
+
+        self.last_known_size = size;
+        Ok(())
     }
 
-    /// Queries the backend for size and resizes if it doesn't match the previous size.
-    pub fn autoresize(&mut self) -> io::Result<()> {
-        if self.viewport.resize_behavior == ResizeBehavior::Auto {
-            let size = self.size()?;
-            if size != self.viewport.area {
-                self.resize(size)?;
-            }
-        };
-        Ok(())
+    fn set_viewport_area(&mut self, area: Rect) {
+        self.viewport.area = area;
+        self.buffers[self.current].resize(area);
+        self.buffers[1 - self.current].resize(area);
+        event!(Level::DEBUG, area = ?area, "viewport changed");
     }
 
     /// Synchronizes terminal size, calls the rendering closure, flushes the current internal state
@@ -259,9 +304,12 @@ where
     where
         F: FnOnce(&mut Frame<B>),
     {
+        let span = span!(Level::DEBUG, "draw");
+        let _guard = span.enter();
+
         // Autoresize - otherwise we get glitches if shrinking or potential desync between widgets
         // and the terminal (if growing), which may OOB.
-        self.autoresize()?;
+        self.resize()?;
 
         let mut frame = self.get_frame();
         f(&mut frame);
@@ -287,9 +335,12 @@ where
 
         // Flush
         self.backend.flush()?;
+
+        event!(Level::DEBUG, "completed frame");
+
         Ok(CompletedFrame {
             buffer: &self.buffers[1 - self.current],
-            area: self.viewport.area,
+            area: self.last_known_size,
         })
     }
 
@@ -310,12 +361,28 @@ where
     }
 
     pub fn set_cursor(&mut self, x: u16, y: u16) -> io::Result<()> {
-        self.backend.set_cursor(x, y)
+        self.backend.set_cursor(x, y)?;
+        self.last_known_cursor_pos = (x, y);
+        Ok(())
     }
 
     /// Clear the terminal and force a full redraw on the next draw call.
     pub fn clear(&mut self) -> io::Result<()> {
-        self.backend.clear()?;
+        event!(Level::DEBUG, "clear");
+        match self.viewport.variant {
+            ViewportVariant::Fullscreen => self.backend.clear(ClearType::All)?,
+            ViewportVariant::Inline(_) => {
+                self.backend
+                    .set_cursor(self.viewport.area.left(), self.viewport.area.top())?;
+                self.backend.clear(ClearType::AfterCursor)?;
+            }
+            ViewportVariant::Fixed(area) => {
+                for row in area.top()..area.bottom() {
+                    self.backend.set_cursor(0, row)?;
+                    self.backend.clear(ClearType::AfterCursor)?;
+                }
+            }
+        }
         // Reset the back buffer to make sure the next update will redraw everything.
         self.buffers[1 - self.current].reset();
         Ok(())
@@ -325,4 +392,97 @@ where
     pub fn size(&self) -> io::Result<Rect> {
         self.backend.size()
     }
+
+    /// Insert some content before the current inline viewport. This has no effect when the
+    /// viewport is fullscreen.
+    ///
+    /// This function scrolls down the current viewport by the given height. The newly freed space is
+    /// then made available to the `draw_fn` closure through a writable `Buffer`.
+    ///
+    /// Before:
+    /// ```ignore
+    /// +-------------------+
+    /// |                   |
+    /// |      viewport     |
+    /// |                   |
+    /// +-------------------+
+    /// ```
+    ///
+    /// After:
+    /// ```ignore
+    /// +-------------------+
+    /// |      buffer       |
+    /// +-------------------+
+    /// +-------------------+
+    /// |                   |
+    /// |      viewport     |
+    /// |                   |
+    /// +-------------------+
+    /// ```
+    ///
+    /// # Examples
+    ///
+    /// ## Insert a single line before the current viewport
+    ///
+    /// ```rust
+    /// # use tui::widgets::{Paragraph, Widget};
+    /// # use tui::text::{Spans, Span};
+    /// # use tui::style::{Color, Style};
+    /// # use tui::{Terminal};
+    /// # use tui::backend::TestBackend;
+    /// # let backend = TestBackend::new(10, 10);
+    /// # let mut terminal = Terminal::new(backend).unwrap();
+    /// terminal.insert_before(1, |buf| {
+    ///     Paragraph::new(Spans::from(vec![
+    ///         Span::raw("This line will be added "),
+    ///         Span::styled("before", Style::default().fg(Color::Blue)),
+    ///         Span::raw(" the current viewport")
+    ///     ])).render(buf.area, buf);
+    /// });
+    /// ```
+    pub fn insert_before<F>(&mut self, height: u16, draw_fn: F) -> io::Result<()>
+    where
+        F: FnOnce(&mut Buffer),
+    {
+        let span = span!(Level::DEBUG, "insert_before");
+        let _guard = span.enter();
+        if !matches!(self.viewport.variant, ViewportVariant::Inline(_)) {
+            return Ok(());
+        }
+
+        self.clear()?;
+        let height = height.min(self.last_known_size.height);
+        self.backend.append_lines(height)?;
+        let missing_lines =
+            height.saturating_sub(self.last_known_size.bottom() - self.viewport.area.top());
+        let area = Rect {
+            x: self.viewport.area.left(),
+            y: self.viewport.area.top().saturating_sub(missing_lines),
+            width: self.viewport.area.width,
+            height,
+        };
+        let mut buffer = Buffer::empty(area);
+
+        draw_fn(&mut buffer);
+
+        let iter = buffer.content.iter().enumerate().map(|(i, c)| {
+            let (x, y) = buffer.pos_of(i);
+            (x, y, c)
+        });
+        self.backend.draw(iter)?;
+        self.backend.flush()?;
+
+        let remaining_lines = self.last_known_size.height - area.bottom();
+        let missing_lines = self.viewport.area.height.saturating_sub(remaining_lines);
+        self.backend.append_lines(self.viewport.area.height)?;
+
+        self.set_viewport_area(Rect {
+            x: area.left(),
+            y: area.bottom().saturating_sub(missing_lines),
+            width: area.width,
+            height: self.viewport.area.height,
+        });
+
+        Ok(())
+    }
 }

src/text.rs

@@ -194,15 +194,9 @@ impl<'a> From<&'a str> for Span<'a> {
 }
 
 /// A string composed of clusters of graphemes, each with their own style.
-#[derive(Debug, Clone, PartialEq)]
+#[derive(Debug, Clone, PartialEq, Default)]
 pub struct Spans<'a>(pub Vec<Span<'a>>);
 
-impl<'a> Default for Spans<'a> {
-    fn default() -> Spans<'a> {
-        Spans(Vec::new())
-    }
-}
-
 impl<'a> Spans<'a> {
     /// Returns the width of the underlying string.
     ///
@@ -279,17 +273,11 @@ impl<'a> From<Spans<'a>> for String {
 /// text.extend(Text::styled("Some more lines\nnow with more style!", style));
 /// assert_eq!(6, text.height());
 /// ```
-#[derive(Debug, Clone, PartialEq)]
+#[derive(Debug, Clone, PartialEq, Default)]
 pub struct Text<'a> {
     pub lines: Vec<Spans<'a>>,
 }
 
-impl<'a> Default for Text<'a> {
-    fn default() -> Text<'a> {
-        Text { lines: Vec::new() }
-    }
-}
-
 impl<'a> Text<'a> {
     /// Create some text (potentially multiple lines) with no style.
     ///

src/widgets/canvas/mod.rs

@@ -14,6 +14,7 @@ use crate::{
     layout::Rect,
     style::{Color, Style},
     symbols,
+    text::Spans,
     widgets::{Block, Widget},
 };
 use std::fmt::Debug;
@@ -26,10 +27,9 @@ pub trait Shape {
 /// Label to draw some text on the canvas
 #[derive(Debug, Clone)]
 pub struct Label<'a> {
-    pub x: f64,
-    pub y: f64,
-    pub text: &'a str,
-    pub color: Color,
+    x: f64,
+    y: f64,
+    spans: Spans<'a>,
 }
 
 #[derive(Debug, Clone)]
@@ -293,8 +293,15 @@ impl<'a> Context<'a> {
     }
 
     /// Print a string on the canvas at the given position
-    pub fn print(&mut self, x: f64, y: f64, text: &'a str, color: Color) {
-        self.labels.push(Label { x, y, text, color });
+    pub fn print<T>(&mut self, x: f64, y: f64, spans: T)
+    where
+        T: Into<Spans<'a>>,
+    {
+        self.labels.push(Label {
+            x,
+            y,
+            spans: spans.into(),
+        });
     }
 
     /// Push the last layer if necessary
@@ -433,6 +440,8 @@ where
             None => area,
         };
 
+        buf.set_style(canvas_area, Style::default().bg(self.background_color));
+
         let width = canvas_area.width as usize;
 
         let painter = match self.painter {
@@ -464,14 +473,12 @@ where
                     let (x, y) = (i % width, i / width);
                     buf.get_mut(x as u16 + canvas_area.left(), y as u16 + canvas_area.top())
                         .set_char(ch)
-                        .set_fg(color)
-                        .set_bg(self.background_color);
+                        .set_fg(color);
                 }
             }
         }
 
         // Finally draw the labels
-        let style = Style::default().bg(self.background_color);
         let left = self.x_bounds[0];
         let right = self.x_bounds[1];
         let top = self.y_bounds[1];
@@ -490,13 +497,7 @@ where
         {
             let x = ((label.x - left) * resolution.0 / width) as u16 + canvas_area.left();
             let y = ((top - label.y) * resolution.1 / height) as u16 + canvas_area.top();
-            buf.set_stringn(
-                x,
-                y,
-                label.text,
-                (canvas_area.right() - x) as usize,
-                style.fg(label.color),
-            );
+            buf.set_spans(x, y, &label.spans, canvas_area.right() - x);
         }
     }
 }

src/widgets/canvas/world.rs

@@ -6122,6 +6122,7 @@ pub static WORLD_LOW_RESOLUTION: [(f64, f64); 1166] = [
     (120.43, 16.43),
     (121.72, 18.40),
     (125.34, 9.79),
+    #[allow(clippy::approx_constant)]
     (125.56, 6.28),
     (122.38, 7.00),
     (125.10, 9.38),

src/widgets/chart.rs

@@ -1,3 +1,8 @@
+use std::{borrow::Cow, cmp::max};
+
+use unicode_width::UnicodeWidthStr;
+
+use crate::layout::Alignment;
 use crate::{
     buffer::Buffer,
     layout::{Constraint, Rect},
@@ -9,8 +14,6 @@ use crate::{
         Block, Borders, Widget,
     },
 };
-use std::{borrow::Cow, cmp::max};
-use unicode_width::UnicodeWidthStr;
 
 /// An X or Y axis for the chart widget
 #[derive(Debug, Clone)]
@@ -23,6 +26,8 @@ pub struct Axis<'a> {
     labels: Option<Vec<Span<'a>>>,
     /// The style used to draw the axis itself
     style: Style,
+    /// The alignment of the labels of the Axis
+    labels_alignment: Alignment,
 }
 
 impl<'a> Default for Axis<'a> {
@@ -32,6 +37,7 @@ impl<'a> Default for Axis<'a> {
             bounds: [0.0, 0.0],
             labels: None,
             style: Default::default(),
+            labels_alignment: Alignment::Left,
         }
     }
 }
@@ -71,6 +77,15 @@ impl<'a> Axis<'a> {
         self.style = style;
         self
     }
+
+    /// Defines the alignment of the labels of the axis.
+    /// The alignment behaves differently based on the axis:
+    /// - Y-Axis: The labels are aligned within the area on the left of the axis
+    /// - X-Axis: The first X-axis label is aligned relative to the Y-axis
+    pub fn labels_alignment(mut self, alignment: Alignment) -> Axis<'a> {
+        self.labels_alignment = alignment;
+        self
+    }
 }
 
 /// Used to determine which style of graphing to use
@@ -141,7 +156,7 @@ impl<'a> Dataset<'a> {
 
 /// A container that holds all the infos about where to display each elements of the chart (axis,
 /// labels, legend, ...).
-#[derive(Debug, Clone, PartialEq)]
+#[derive(Debug, Clone, PartialEq, Default)]
 struct ChartLayout {
     /// Location of the title of the x axis
     title_x: Option<(u16, u16)>,
@@ -161,21 +176,6 @@ struct ChartLayout {
     graph_area: Rect,
 }
 
-impl Default for ChartLayout {
-    fn default() -> ChartLayout {
-        ChartLayout {
-            title_x: None,
-            title_y: None,
-            label_x: None,
-            label_y: None,
-            axis_x: None,
-            axis_y: None,
-            legend_area: None,
-            graph_area: Rect::default(),
-        }
-    }
-}
-
 /// A widget to plot one or more dataset in a cartesian coordinate system
 ///
 /// # Examples
@@ -297,7 +297,7 @@ impl<'a> Chart<'a> {
         }
 
         layout.label_y = self.y_axis.labels.as_ref().and(Some(x));
-        x += self.max_width_of_labels_left_of_y_axis(area);
+        x += self.max_width_of_labels_left_of_y_axis(area, self.y_axis.labels.is_some());
 
         if self.x_axis.labels.is_some() && y > area.top() {
             layout.axis_x = Some(y);
@@ -353,17 +353,26 @@ impl<'a> Chart<'a> {
         layout
     }
 
-    fn max_width_of_labels_left_of_y_axis(&self, area: Rect) -> u16 {
+    fn max_width_of_labels_left_of_y_axis(&self, area: Rect, has_y_axis: bool) -> u16 {
         let mut max_width = self
             .y_axis
             .labels
             .as_ref()
             .map(|l| l.iter().map(Span::width).max().unwrap_or_default() as u16)
             .unwrap_or_default();
-        if let Some(ref x_labels) = self.x_axis.labels {
-            if !x_labels.is_empty() {
-                max_width = max(max_width, x_labels[0].content.width() as u16);
-            }
+
+        if let Some(first_x_label) = self.x_axis.labels.as_ref().and_then(|labels| labels.get(0)) {
+            let first_label_width = first_x_label.content.width() as u16;
+            let width_left_of_y_axis = match self.x_axis.labels_alignment {
+                Alignment::Left => {
+                    // The last character of the label should be below the Y-Axis when it exists, not on its left
+                    let y_axis_offset = if has_y_axis { 1 } else { 0 };
+                    first_label_width.saturating_sub(y_axis_offset)
+                }
+                Alignment::Center => first_label_width / 2,
+                Alignment::Right => 0,
+            };
+            max_width = max(max_width, width_left_of_y_axis);
         }
         // labels of y axis and first label of x axis can take at most 1/3rd of the total width
         max_width.min(area.width / 3)
@@ -385,26 +394,73 @@ impl<'a> Chart<'a> {
         if labels_len < 2 {
             return;
         }
-        let width_between_ticks = graph_area.width / (labels_len - 1);
-        for (i, label) in labels.iter().enumerate() {
-            let label_width = label.width() as u16;
-            let label_width = if i == 0 {
-                // the first label is put between the left border of the chart and the y axis.
-                graph_area
-                    .left()
-                    .saturating_sub(chart_area.left())
-                    .min(label_width)
-            } else {
-                // other labels are put on the left of each tick on the x axis
-                width_between_ticks.min(label_width)
-            };
-            buf.set_span(
-                graph_area.left() + i as u16 * width_between_ticks - label_width,
-                y,
-                label,
-                label_width,
-            );
+
+        let width_between_ticks = graph_area.width / labels_len;
+
+        let label_area = self.first_x_label_area(
+            y,
+            labels.first().unwrap().width() as u16,
+            width_between_ticks,
+            chart_area,
+            graph_area,
+        );
+
+        let label_alignment = match self.x_axis.labels_alignment {
+            Alignment::Left => Alignment::Right,
+            Alignment::Center => Alignment::Center,
+            Alignment::Right => Alignment::Left,
+        };
+
+        Self::render_label(buf, labels.first().unwrap(), label_area, label_alignment);
+
+        for (i, label) in labels[1..labels.len() - 1].iter().enumerate() {
+            // We add 1 to x (and width-1 below) to leave at least one space before each intermediate labels
+            let x = graph_area.left() + (i + 1) as u16 * width_between_ticks + 1;
+            let label_area = Rect::new(x, y, width_between_ticks.saturating_sub(1), 1);
+
+            Self::render_label(buf, label, label_area, Alignment::Center);
         }
+
+        let x = graph_area.right() - width_between_ticks;
+        let label_area = Rect::new(x, y, width_between_ticks, 1);
+        // The last label should be aligned Right to be at the edge of the graph area
+        Self::render_label(buf, labels.last().unwrap(), label_area, Alignment::Right);
+    }
+
+    fn first_x_label_area(
+        &self,
+        y: u16,
+        label_width: u16,
+        max_width_after_y_axis: u16,
+        chart_area: Rect,
+        graph_area: Rect,
+    ) -> Rect {
+        let (min_x, max_x) = match self.x_axis.labels_alignment {
+            Alignment::Left => (chart_area.left(), graph_area.left()),
+            Alignment::Center => (
+                chart_area.left(),
+                graph_area.left() + max_width_after_y_axis.min(label_width),
+            ),
+            Alignment::Right => (
+                graph_area.left().saturating_sub(1),
+                graph_area.left() + max_width_after_y_axis,
+            ),
+        };
+
+        Rect::new(min_x, y, max_x - min_x, 1)
+    }
+
+    fn render_label(buf: &mut Buffer, label: &Span, label_area: Rect, alignment: Alignment) {
+        let label_width = label.width() as u16;
+        let bounded_label_width = label_area.width.min(label_width);
+
+        let x = match alignment {
+            Alignment::Left => label_area.left(),
+            Alignment::Center => label_area.left() + label_area.width / 2 - bounded_label_width / 2,
+            Alignment::Right => label_area.right() - bounded_label_width,
+        };
+
+        buf.set_span(x, label_area.top(), label, bounded_label_width);
     }
 
     fn render_y_labels(
@@ -420,11 +476,16 @@ impl<'a> Chart<'a> {
         };
         let labels = self.y_axis.labels.as_ref().unwrap();
         let labels_len = labels.len() as u16;
-        let label_width = graph_area.left().saturating_sub(chart_area.left());
         for (i, label) in labels.iter().enumerate() {
             let dy = i as u16 * (graph_area.height - 1) / (labels_len - 1);
             if dy < graph_area.bottom() {
-                buf.set_span(x, graph_area.bottom() - 1 - dy, label, label_width as u16);
+                let label_area = Rect::new(
+                    x,
+                    graph_area.bottom().saturating_sub(1) - dy,
+                    (graph_area.left() - chart_area.left()).saturating_sub(1),
+                    1,
+                );
+                Self::render_label(buf, label, label_area, self.y_axis.labels_alignment);
             }
         }
     }

src/widgets/list.rs

@@ -7,21 +7,12 @@ use crate::{
 };
 use unicode_width::UnicodeWidthStr;
 
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, Default)]
 pub struct ListState {
     offset: usize,
     selected: Option<usize>,
 }
 
-impl Default for ListState {
-    fn default() -> ListState {
-        ListState {
-            offset: 0,
-            selected: None,
-        }
-    }
-}
-
 impl ListState {
     pub fn selected(&self) -> Option<usize> {
         self.selected
@@ -87,6 +78,8 @@ pub struct List<'a> {
     highlight_style: Style,
     /// Symbol in front of the selected item (Shift all items to the right)
     highlight_symbol: Option<&'a str>,
+    /// Whether to repeat the highlight symbol for each line of the selected item
+    repeat_highlight_symbol: bool,
 }
 
 impl<'a> List<'a> {
@@ -101,6 +94,7 @@ impl<'a> List<'a> {
             start_corner: Corner::TopLeft,
             highlight_style: Style::default(),
             highlight_symbol: None,
+            repeat_highlight_symbol: false,
         }
     }
 
@@ -124,6 +118,11 @@ impl<'a> List<'a> {
         self
     }
 
+    pub fn repeat_highlight_symbol(mut self, repeat: bool) -> List<'a> {
+        self.repeat_highlight_symbol = repeat;
+        self
+    }
+
     pub fn start_corner(mut self, corner: Corner) -> List<'a> {
         self.start_corner = corner;
         self
@@ -227,19 +226,27 @@ impl<'a> StatefulWidget for List<'a> {
             buf.set_style(area, item_style);
 
             let is_selected = state.selected.map(|s| s == i).unwrap_or(false);
-            let elem_x = if has_selection {
-                let symbol = if is_selected {
+            for (j, line) in item.content.lines.iter().enumerate() {
+                // if the item is selected, we need to display the hightlight symbol:
+                // - either for the first line of the item only,
+                // - or for each line of the item if the appropriate option is set
+                let symbol = if is_selected && (j == 0 || self.repeat_highlight_symbol) {
                     highlight_symbol
                 } else {
                     &blank_symbol
                 };
-                let (x, _) = buf.set_stringn(x, y, symbol, list_area.width as usize, item_style);
-                x
-            } else {
-                x
-            };
-            let max_element_width = (list_area.width - (elem_x - x)) as usize;
-            for (j, line) in item.content.lines.iter().enumerate() {
+                let (elem_x, max_element_width) = if has_selection {
+                    let (elem_x, _) = buf.set_stringn(
+                        x,
+                        y + j as u16,
+                        symbol,
+                        list_area.width as usize,
+                        item_style,
+                    );
+                    (elem_x, (list_area.width - (elem_x - x)) as u16)
+                } else {
+                    (x, list_area.width)
+                };
                 buf.set_spans(elem_x, y + j as u16, line, max_element_width as u16);
             }
             if is_selected {

src/widgets/mod.rs

@@ -87,7 +87,7 @@ pub trait Widget {
 /// ```rust,no_run
 /// # use std::io;
 /// # use tui::Terminal;
-/// # use tui::backend::{Backend, TermionBackend};
+/// # use tui::backend::{Backend, TestBackend};
 /// # use tui::widgets::{Widget, List, ListItem, ListState};
 ///
 /// // Let's say we have some events to display.
@@ -154,9 +154,8 @@ pub trait Widget {
 ///     }
 /// }
 ///
-/// let stdout = io::stdout();
-/// let backend = TermionBackend::new(stdout);
-/// let mut terminal = Terminal::new(backend).unwrap();
+/// # let backend = TestBackend::new(5, 5);
+/// # let mut terminal = Terminal::new(backend).unwrap();
 ///
 /// let mut events = Events::new(vec![
 ///     String::from("Item 1"),

src/widgets/reflow.rs

@@ -403,8 +403,8 @@ mod test {
         let text = "コンピュータ上で文字を扱う場合、典型的には文字による通信を行う場合にその両端点\
                     では、";
         let (word_wrapper, word_wrapper_width) =
-            run_composer(Composer::WordWrapper { trim: true }, &text, width);
-        let (line_truncator, _) = run_composer(Composer::LineTruncator, &text, width);
+            run_composer(Composer::WordWrapper { trim: true }, text, width);
+        let (line_truncator, _) = run_composer(Composer::LineTruncator, text, width);
         assert_eq!(line_truncator, vec!["コンピュータ上で文字"]);
         let wrapped = vec![
             "コンピュータ上で文字",

src/widgets/table.rs

@@ -335,21 +335,12 @@ impl<'a> Table<'a> {
     }
 }
 
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, Default)]
 pub struct TableState {
     offset: usize,
     selected: Option<usize>,
 }
 
-impl Default for TableState {
-    fn default() -> TableState {
-        TableState {
-            offset: 0,
-            selected: None,
-        }
-    }
-}
-
 impl TableState {
     pub fn selected(&self) -> Option<usize> {
         self.selected

tests/backend_termion.rs

@@ -8,14 +8,14 @@ fn backend_termion_should_only_write_diffs() -> Result<(), Box<dyn std::error::E
     {
         use tui::{
             backend::TermionBackend, layout::Rect, widgets::Paragraph, Terminal, TerminalOptions,
-            Viewport,
+            ViewportVariant,
         };
         let backend = TermionBackend::new(&mut stdout);
         let area = Rect::new(0, 0, 3, 1);
         let mut terminal = Terminal::with_options(
             backend,
             TerminalOptions {
-                viewport: Viewport::fixed(area),
+                viewport: ViewportVariant::Fixed(area),
             },
         )?;
         terminal.draw(|f| {

tests/widgets_canvas.rs

@@ -0,0 +1,42 @@
+use tui::{
+    backend::TestBackend,
+    buffer::Buffer,
+    style::{Color, Style},
+    text::Span,
+    widgets::canvas::Canvas,
+    Terminal,
+};
+
+#[test]
+fn widgets_canvas_draw_labels() {
+    let backend = TestBackend::new(5, 5);
+    let mut terminal = Terminal::new(backend).unwrap();
+    terminal
+        .draw(|f| {
+            let label = String::from("test");
+            let canvas = Canvas::default()
+                .background_color(Color::Yellow)
+                .x_bounds([0.0, 5.0])
+                .y_bounds([0.0, 5.0])
+                .paint(|ctx| {
+                    ctx.print(
+                        0.0,
+                        0.0,
+                        Span::styled(label.clone(), Style::default().fg(Color::Blue)),
+                    );
+                });
+            f.render_widget(canvas, f.size());
+        })
+        .unwrap();
+
+    let mut expected = Buffer::with_lines(vec!["    ", "    ", "     ", "     ", "test "]);
+    for row in 0..5 {
+        for col in 0..5 {
+            expected.get_mut(col, row).set_bg(Color::Yellow);
+        }
+    }
+    for col in 0..4 {
+        expected.get_mut(col, 4).set_fg(Color::Blue);
+    }
+    terminal.backend().assert_buffer(&expected)
+}

tests/widgets_chart.rs

@@ -1,3 +1,4 @@
+use tui::layout::Alignment;
 use tui::{
     backend::TestBackend,
     buffer::Buffer,
@@ -13,6 +14,22 @@ fn create_labels<'a>(labels: &'a [&'a str]) -> Vec<Span<'a>> {
     labels.iter().map(|l| Span::from(*l)).collect()
 }
 
+fn axis_test_case<S>(width: u16, height: u16, x_axis: Axis, y_axis: Axis, lines: Vec<S>)
+where
+    S: AsRef<str>,
+{
+    let backend = TestBackend::new(width, height);
+    let mut terminal = Terminal::new(backend).unwrap();
+    terminal
+        .draw(|f| {
+            let chart = Chart::new(vec![]).x_axis(x_axis).y_axis(y_axis);
+            f.render_widget(chart, f.size());
+        })
+        .unwrap();
+    let expected = Buffer::with_lines(lines);
+    terminal.backend().assert_buffer(&expected);
+}
+
 #[test]
 fn widgets_chart_can_render_on_small_areas() {
     let test_case = |width, height| {
@@ -49,33 +66,26 @@ fn widgets_chart_can_render_on_small_areas() {
 
 #[test]
 fn widgets_chart_handles_long_labels() {
-    let test_case = |x_labels, y_labels, lines| {
-        let backend = TestBackend::new(10, 5);
-        let mut terminal = Terminal::new(backend).unwrap();
-        terminal
-            .draw(|f| {
-                let datasets = vec![Dataset::default()
-                    .marker(symbols::Marker::Braille)
-                    .style(Style::default().fg(Color::Magenta))
-                    .data(&[(2.0, 2.0)])];
-                let mut x_axis = Axis::default().bounds([0.0, 1.0]);
-                if let Some((left_label, right_label)) = x_labels {
-                    x_axis = x_axis.labels(vec![Span::from(left_label), Span::from(right_label)]);
-                }
-                let mut y_axis = Axis::default().bounds([0.0, 1.0]);
-                if let Some((left_label, right_label)) = y_labels {
-                    y_axis = y_axis.labels(vec![Span::from(left_label), Span::from(right_label)]);
-                }
-                let chart = Chart::new(datasets).x_axis(x_axis).y_axis(y_axis);
-                f.render_widget(chart, f.size());
-            })
-            .unwrap();
-        let expected = Buffer::with_lines(lines);
-        terminal.backend().assert_buffer(&expected);
+    let test_case = |x_labels, y_labels, x_alignment, lines| {
+        let mut x_axis = Axis::default().bounds([0.0, 1.0]);
+        if let Some((left_label, right_label)) = x_labels {
+            x_axis = x_axis
+                .labels(vec![Span::from(left_label), Span::from(right_label)])
+                .labels_alignment(x_alignment);
+        }
+
+        let mut y_axis = Axis::default().bounds([0.0, 1.0]);
+        if let Some((left_label, right_label)) = y_labels {
+            y_axis = y_axis.labels(vec![Span::from(left_label), Span::from(right_label)]);
+        }
+
+        axis_test_case(10, 5, x_axis, y_axis, lines);
     };
+
     test_case(
         Some(("AAAA", "B")),
         None,
+        Alignment::Left,
         vec![
             "          ",
             "          ",
@@ -87,6 +97,7 @@ fn widgets_chart_handles_long_labels() {
     test_case(
         Some(("A", "BBBB")),
         None,
+        Alignment::Left,
         vec![
             "          ",
             "          ",
@@ -98,6 +109,7 @@ fn widgets_chart_handles_long_labels() {
     test_case(
         Some(("AAAAAAAAAAA", "B")),
         None,
+        Alignment::Left,
         vec![
             "          ",
             "          ",
@@ -109,6 +121,7 @@ fn widgets_chart_handles_long_labels() {
     test_case(
         Some(("A", "B")),
         Some(("CCCCCCC", "D")),
+        Alignment::Left,
         vec![
             "D  │      ",
             "   │      ",
@@ -117,6 +130,129 @@ fn widgets_chart_handles_long_labels() {
             "   A     B",
         ],
     );
+    test_case(
+        Some(("AAAAAAAAAA", "B")),
+        Some(("C", "D")),
+        Alignment::Center,
+        vec![
+            "D  │      ",
+            "   │      ",
+            "C  │      ",
+            "   └──────",
+            "AAAAAAA  B",
+        ],
+    );
+    test_case(
+        Some(("AAAAAAA", "B")),
+        Some(("C", "D")),
+        Alignment::Right,
+        vec![
+            "D│        ",
+            " │        ",
+            "C│        ",
+            " └────────",
+            " AAAAA   B",
+        ],
+    );
+    test_case(
+        Some(("AAAAAAA", "BBBBBBB")),
+        Some(("C", "D")),
+        Alignment::Right,
+        vec![
+            "D│        ",
+            " │        ",
+            "C│        ",
+            " └────────",
+            " AAAAABBBB",
+        ],
+    );
+}
+
+#[test]
+fn widgets_chart_handles_x_axis_labels_alignments() {
+    let test_case = |y_alignment, lines| {
+        let x_axis = Axis::default()
+            .labels(vec![Span::from("AAAA"), Span::from("B"), Span::from("C")])
+            .labels_alignment(y_alignment);
+
+        let y_axis = Axis::default();
+
+        axis_test_case(10, 5, x_axis, y_axis, lines);
+    };
+
+    test_case(
+        Alignment::Left,
+        vec![
+            "          ",
+            "          ",
+            "          ",
+            "   ───────",
+            "AAA   B  C",
+        ],
+    );
+    test_case(
+        Alignment::Center,
+        vec![
+            "          ",
+            "          ",
+            "          ",
+            "  ────────",
+            "AAAA B   C",
+        ],
+    );
+    test_case(
+        Alignment::Right,
+        vec![
+            "          ",
+            "          ",
+            "          ",
+            "──────────",
+            "AAA  B   C",
+        ],
+    );
+}
+
+#[test]
+fn widgets_chart_handles_y_axis_labels_alignments() {
+    let test_case = |y_alignment, lines| {
+        let x_axis = Axis::default().labels(create_labels(&["AAAAA", "B"]));
+
+        let y_axis = Axis::default()
+            .labels(create_labels(&["C", "D"]))
+            .labels_alignment(y_alignment);
+
+        axis_test_case(20, 5, x_axis, y_axis, lines);
+    };
+    test_case(
+        Alignment::Left,
+        vec![
+            "D   │               ",
+            "    │               ",
+            "C   │               ",
+            "    └───────────────",
+            "AAAAA              B",
+        ],
+    );
+    test_case(
+        Alignment::Center,
+        vec![
+            "  D │               ",
+            "    │               ",
+            "  C │               ",
+            "    └───────────────",
+            "AAAAA              B",
+        ],
+    );
+    test_case(
+        Alignment::Right,
+        vec![
+            "   D│               ",
+            "    │               ",
+            "   C│               ",
+            "    └───────────────",
+            "AAAAA              B",
+        ],
+    );
 }
 
 #[test]
@@ -329,7 +465,7 @@ fn widgets_chart_can_have_a_legend() {
         "│    │ ••                                               •• │",
         "│0.0 │•                                              X Axis│",
         "│    └─────────────────────────────────────────────────────│",
-        "│  0.0                      50.0                     100.0 │",
+        "│  0.0                        50.0                    100.0│",
         "└──────────────────────────────────────────────────────────┘",
     ]);
 

tests/widgets_list.rs

@@ -4,6 +4,7 @@ use tui::{
     layout::Rect,
     style::{Color, Style},
     symbols,
+    text::Spans,
     widgets::{Block, Borders, List, ListItem, ListState},
     Terminal,
 };
@@ -126,3 +127,74 @@ fn widgets_list_should_clamp_offset_if_items_are_removed() {
     let expected = Buffer::with_lines(vec!["   Item 3 ", "          ", "          ", "          "]);
     terminal.backend().assert_buffer(&expected);
 }
+
+#[test]
+fn widgets_list_should_display_multiline_items() {
+    let backend = TestBackend::new(10, 6);
+    let mut terminal = Terminal::new(backend).unwrap();
+    let mut state = ListState::default();
+    state.select(Some(1));
+    terminal
+        .draw(|f| {
+            let size = f.size();
+            let items = vec![
+                ListItem::new(vec![Spans::from("Item 1"), Spans::from("Item 1a")]),
+                ListItem::new(vec![Spans::from("Item 2"), Spans::from("Item 2b")]),
+                ListItem::new(vec![Spans::from("Item 3"), Spans::from("Item 3c")]),
+            ];
+            let list = List::new(items)
+                .highlight_style(Style::default().bg(Color::Yellow))
+                .highlight_symbol(">> ");
+            f.render_stateful_widget(list, size, &mut state);
+        })
+        .unwrap();
+    let mut expected = Buffer::with_lines(vec![
+        "   Item 1 ",
+        "   Item 1a",
+        ">> Item 2 ",
+        "   Item 2b",
+        "   Item 3 ",
+        "   Item 3c",
+    ]);
+    for x in 0..10 {
+        expected.get_mut(x, 2).set_bg(Color::Yellow);
+        expected.get_mut(x, 3).set_bg(Color::Yellow);
+    }
+    terminal.backend().assert_buffer(&expected);
+}
+
+#[test]
+fn widgets_list_should_repeat_highlight_symbol() {
+    let backend = TestBackend::new(10, 6);
+    let mut terminal = Terminal::new(backend).unwrap();
+    let mut state = ListState::default();
+    state.select(Some(1));
+    terminal
+        .draw(|f| {
+            let size = f.size();
+            let items = vec![
+                ListItem::new(vec![Spans::from("Item 1"), Spans::from("Item 1a")]),
+                ListItem::new(vec![Spans::from("Item 2"), Spans::from("Item 2b")]),
+                ListItem::new(vec![Spans::from("Item 3"), Spans::from("Item 3c")]),
+            ];
+            let list = List::new(items)
+                .highlight_style(Style::default().bg(Color::Yellow))
+                .highlight_symbol(">> ")
+                .repeat_highlight_symbol(true);
+            f.render_stateful_widget(list, size, &mut state);
+        })
+        .unwrap();
+    let mut expected = Buffer::with_lines(vec![
+        "   Item 1 ",
+        "   Item 1a",
+        ">> Item 2 ",
+        ">> Item 2b",
+        "   Item 3 ",
+        "   Item 3c",
+    ]);
+    for x in 0..10 {
+        expected.get_mut(x, 2).set_bg(Color::Yellow);
+        expected.get_mut(x, 3).set_bg(Color::Yellow);
+    }
+    terminal.backend().assert_buffer(&expected);
+}