Josh McKinney 8d60e96b2b
refactor(examples): use crossterm event methods (#1792)
Crossterm 0.29 introduced methods to easily check / extract the event
type. E.g. as_key_press_event() and is_key_press(). This commit
updates the examples to use these methods instead of matching on
the event type. This makes the code cleaner and easier to read.

Also does a general cleanup of the event handling code in the examples.
2025-05-10 10:35:12 -07:00

101 lines
3.2 KiB
Rust

//! # [Ratatui] `Sparkline` example
//!
//! The latest version of this example is available in the [widget examples] folder in the
//! repository.
//!
//! Please note that the examples are designed to be run against the `main` branch of the Github
//! repository. This means that you may not be able to compile with the latest release version on
//! crates.io, or the one that you have installed locally.
//!
//! See the [examples readme] for more information on finding examples that match the version of the
//! library you are using.
//!
//! [Ratatui]: https://github.com/ratatui/ratatui
//! [widget examples]: https://github.com/ratatui/ratatui/blob/main/ratatui-widgets/examples
//! [examples readme]: https://github.com/ratatui/ratatui/blob/main/examples/README.md
use core::time::Duration;
use color_eyre::Result;
use crossterm::event;
use ratatui::layout::{Constraint, Layout, Rect};
use ratatui::style::{Color, Style, Stylize};
use ratatui::text::{Line, Span};
use ratatui::widgets::{RenderDirection, Sparkline};
use ratatui::{symbols, DefaultTerminal, Frame};
fn main() -> Result<()> {
color_eyre::install()?;
let terminal = ratatui::init();
let result = run(terminal);
ratatui::restore();
result
}
/// Run the application.
fn run(mut terminal: DefaultTerminal) -> Result<()> {
loop {
terminal.draw(render)?;
// Ensure that the animations renders at 50 FPS (GIF speed)
if !event::poll(Duration::from_secs_f64(1.0 / 50.0))? {
continue;
}
if event::read()?.is_key_press() {
return Ok(());
}
}
}
/// Render the UI with various sparklines.
fn render(frame: &mut Frame) {
let constraints = [
Constraint::Length(1),
Constraint::Max(2),
Constraint::Fill(1),
Constraint::Fill(1),
];
let [top, first, second, _] = Layout::vertical(constraints).spacing(1).areas(frame.area());
let title = Line::from_iter([
Span::from("Sparkline Widget").bold(),
Span::from(" (Press 'q' to quit)"),
]);
frame.render_widget(title.centered(), top);
render_sparkline(frame, first);
render_sin_wave(frame, second);
}
/// Render a sparkline with some sample data.
pub fn render_sparkline(frame: &mut Frame, area: Rect) {
let data = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10].repeat(area.width.into());
let sparkline = Sparkline::default()
.data(&data)
.max(10)
.direction(RenderDirection::LeftToRight)
.style(Color::Cyan);
frame.render_widget(sparkline, area);
}
/// Render a sin wave based on the current frame count.
pub fn render_sin_wave(frame: &mut Frame, area: Rect) {
let phase_shift = frame.count() as f64 * 0.2;
let data: Vec<u64> = (0..area.width)
.map(|v| {
let angle = f64::from(v) * 0.5 + phase_shift;
((angle.sin() * 3.0 + 3.0) * 10.0).round() as u64
})
.collect();
let sparkline = Sparkline::default()
.data(&data)
.max(100)
.direction(RenderDirection::RightToLeft)
.style(Style::default().magenta().on_black())
.absent_value_style(Color::Red)
.absent_value_symbol(symbols::shade::FULL);
frame.render_widget(sparkline, area);
}