layout.rs

use crossterm::{
    event::{self, DisableMouseCapture, EnableMouseCapture, Event, KeyCode},
    execute,
    terminal::{disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen},
};
use std::{error::Error, io};
use tui::{
    backend::{Backend, CrosstermBackend},
    layout::{Constraint, Direction, Layout},
    widgets::{Block, Borders},
    Frame, Terminal,
};

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 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| 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]);
}