mirror of https://github.com/fdehau/tui-rs
Merge branch 'master' into patch-1
commit
3948a00058
@ -0,0 +1,142 @@
|
||||
//! How to use a panic hook to reset the terminal before printing the panic to
|
||||
//! the terminal.
|
||||
//!
|
||||
//! When exiting normally or when handling `Result::Err`, we can reset the
|
||||
//! terminal manually at the end of `main` just before we print the error.
|
||||
//!
|
||||
//! Because a panic interrupts the normal control flow, manually resetting the
|
||||
//! terminal at the end of `main` won't do us any good. Instead, we need to
|
||||
//! make sure to set up a panic hook that first resets the terminal before
|
||||
//! handling the panic. This both reuses the standard panic hook to ensure a
|
||||
//! consistent panic handling UX and properly resets the terminal to not
|
||||
//! distort the output.
|
||||
//!
|
||||
//! That's why this example is set up to show both situations, with and without
|
||||
//! the chained panic hook, to see the difference.
|
||||
|
||||
#![deny(clippy::all)]
|
||||
#![warn(clippy::pedantic, clippy::nursery)]
|
||||
|
||||
use std::error::Error;
|
||||
use std::io;
|
||||
|
||||
use crossterm::event::{self, Event, KeyCode};
|
||||
use crossterm::terminal::{disable_raw_mode, enable_raw_mode};
|
||||
use crossterm::terminal::{EnterAlternateScreen, LeaveAlternateScreen};
|
||||
|
||||
use tui::backend::{Backend, CrosstermBackend};
|
||||
use tui::layout::Alignment;
|
||||
use tui::text::Spans;
|
||||
use tui::widgets::{Block, Borders, Paragraph};
|
||||
use tui::{Frame, Terminal};
|
||||
|
||||
type Result<T> = std::result::Result<T, Box<dyn Error>>;
|
||||
|
||||
#[derive(Default)]
|
||||
struct App {
|
||||
hook_enabled: bool,
|
||||
}
|
||||
|
||||
impl App {
|
||||
fn chain_hook(&mut self) {
|
||||
let original_hook = std::panic::take_hook();
|
||||
|
||||
std::panic::set_hook(Box::new(move |panic| {
|
||||
reset_terminal().unwrap();
|
||||
original_hook(panic);
|
||||
}));
|
||||
|
||||
self.hook_enabled = true;
|
||||
}
|
||||
}
|
||||
|
||||
fn main() -> Result<()> {
|
||||
let mut terminal = init_terminal()?;
|
||||
|
||||
let mut app = App::default();
|
||||
let res = run_tui(&mut terminal, &mut app);
|
||||
|
||||
reset_terminal()?;
|
||||
|
||||
if let Err(err) = res {
|
||||
println!("{:?}", err);
|
||||
}
|
||||
|
||||
Ok(())
|
||||
}
|
||||
|
||||
/// Initializes the terminal.
|
||||
fn init_terminal() -> Result<Terminal<CrosstermBackend<io::Stdout>>> {
|
||||
crossterm::execute!(io::stdout(), EnterAlternateScreen)?;
|
||||
enable_raw_mode()?;
|
||||
|
||||
let backend = CrosstermBackend::new(io::stdout());
|
||||
|
||||
let mut terminal = Terminal::new(backend)?;
|
||||
terminal.hide_cursor()?;
|
||||
|
||||
Ok(terminal)
|
||||
}
|
||||
|
||||
/// Resets the terminal.
|
||||
fn reset_terminal() -> Result<()> {
|
||||
disable_raw_mode()?;
|
||||
crossterm::execute!(io::stdout(), LeaveAlternateScreen)?;
|
||||
|
||||
Ok(())
|
||||
}
|
||||
|
||||
/// Runs the TUI loop.
|
||||
fn run_tui<B: Backend>(terminal: &mut Terminal<B>, app: &mut App) -> io::Result<()> {
|
||||
loop {
|
||||
terminal.draw(|f| ui(f, app))?;
|
||||
|
||||
if let Event::Key(key) = event::read()? {
|
||||
match key.code {
|
||||
KeyCode::Char('p') => {
|
||||
panic!("intentional demo panic");
|
||||
}
|
||||
|
||||
KeyCode::Char('e') => {
|
||||
app.chain_hook();
|
||||
}
|
||||
|
||||
_ => {
|
||||
return Ok(());
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/// Render the TUI.
|
||||
fn ui<B: Backend>(f: &mut Frame<B>, app: &App) {
|
||||
let text = vec![
|
||||
if app.hook_enabled {
|
||||
Spans::from("HOOK IS CURRENTLY **ENABLED**")
|
||||
} else {
|
||||
Spans::from("HOOK IS CURRENTLY **DISABLED**")
|
||||
},
|
||||
Spans::from(""),
|
||||
Spans::from("press `p` to panic"),
|
||||
Spans::from("press `e` to enable the terminal-resetting panic hook"),
|
||||
Spans::from("press any other key to quit without panic"),
|
||||
Spans::from(""),
|
||||
Spans::from("when you panic without the chained hook,"),
|
||||
Spans::from("you will likely have to reset your terminal afterwards"),
|
||||
Spans::from("with the `reset` command"),
|
||||
Spans::from(""),
|
||||
Spans::from("with the chained panic hook enabled,"),
|
||||
Spans::from("you should see the panic report as you would without tui"),
|
||||
Spans::from(""),
|
||||
Spans::from("try first without the panic handler to see the difference"),
|
||||
];
|
||||
|
||||
let b = Block::default()
|
||||
.title("Panic Handler Demo")
|
||||
.borders(Borders::ALL);
|
||||
|
||||
let p = Paragraph::new(text).block(b).alignment(Alignment::Center);
|
||||
|
||||
f.render_widget(p, f.size());
|
||||
}
|
Loading…
Reference in New Issue