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
3.4 KiB
Rust

//! # [Ratatui] `List` 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 color_eyre::Result;
use crossterm::event::{self, KeyCode};
use ratatui::layout::{Constraint, Layout, Rect};
use ratatui::style::{Color, Modifier, Style, Stylize};
use ratatui::text::{Line, Span};
use ratatui::widgets::{List, ListDirection, ListState};
use ratatui::{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<()> {
let mut list_state = ListState::default().with_selected(Some(0));
loop {
terminal.draw(|frame| render(frame, &mut list_state))?;
if let Some(key) = event::read()?.as_key_press_event() {
match key.code {
KeyCode::Char('j') | KeyCode::Down => list_state.select_next(),
KeyCode::Char('k') | KeyCode::Up => list_state.select_previous(),
KeyCode::Char('q') | KeyCode::Esc => return Ok(()),
_ => {}
}
}
}
}
/// Render the UI with various lists.
fn render(frame: &mut Frame, list_state: &mut ListState) {
let vertical = Layout::vertical([
Constraint::Length(1),
Constraint::Fill(1),
Constraint::Fill(1),
])
.spacing(1);
let [top, first, second] = vertical.areas(frame.area());
let title = Line::from_iter([
Span::from("List Widget").bold(),
Span::from(" (Press 'q' to quit and arrow keys to navigate)"),
]);
frame.render_widget(title.centered(), top);
render_list(frame, first, list_state);
render_bottom_list(frame, second);
}
/// Render a list.
pub fn render_list(frame: &mut Frame, area: Rect, list_state: &mut ListState) {
let items = ["Item 1", "Item 2", "Item 3", "Item 4"];
let list = List::new(items)
.style(Color::White)
.highlight_style(Modifier::REVERSED)
.highlight_symbol("> ");
frame.render_stateful_widget(list, area, list_state);
}
/// Render a bottom-to-top list.
pub fn render_bottom_list(frame: &mut Frame, area: Rect) {
let items = [
"[Remy]: I'm building one now.\nIt even supports multiline text!",
"[Gusteau]: With enough passion, yes.",
"[Remy]: But can anyone build a TUI in Rust?",
"[Gusteau]: Anyone can cook!",
];
let list = List::new(items)
.style(Color::White)
.highlight_style(Style::new().yellow().italic())
.highlight_symbol("> ".red())
.scroll_padding(1)
.direction(ListDirection::BottomToTop)
.repeat_highlight_symbol(true);
let mut state = ListState::default();
state.select_first();
frame.render_stateful_widget(list, area, &mut state);
}