ratatui/examples/custom_widget.rs

#[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, buffer::Buffer, layout::Rect, style::Style, widgets::Widget, Terminal,
};

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());
    }
}

impl<'a> Label<'a> {
    fn text(mut self, text: &'a str) -> Label<'a> {
        self.text = text;
        self
    }
}

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(|mut f| {
            let size = f.size();
            let label = Label::default().text("Test");
            f.render_widget(label, size);
        })?;

        match events.next()? {
            Event::Input(key) => {
                if key == Key::Char('q') {
                    break;
                }
            }
            _ => {}
        }
    }

    Ok(())
}