1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
|
//! # [Ratatui] Paragraph example
//!
//! The latest version of this example is available in the [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
//! [examples]: https://github.com/ratatui/ratatui/blob/main/examples
//! [examples readme]: https://github.com/ratatui/ratatui/blob/main/examples/README.md
use std::{
io::{self},
time::{Duration, Instant},
};
use color_eyre::Result;
use ratatui::{
buffer::Buffer,
crossterm::event::{self, Event, KeyCode, KeyEventKind},
layout::{Constraint, Layout, Rect},
style::{Color, Stylize},
text::{Line, Masked, Span},
widgets::{Block, Paragraph, Widget, Wrap},
DefaultTerminal,
};
fn main() -> Result<()> {
color_eyre::install()?;
let terminal = ratatui::init();
let app_result = App::new().run(terminal);
ratatui::restore();
app_result
}
#[derive(Debug)]
struct App {
should_exit: bool,
scroll: u16,
last_tick: Instant,
}
impl App {
/// The duration between each tick.
const TICK_RATE: Duration = Duration::from_millis(250);
/// Create a new instance of the app.
fn new() -> Self {
Self {
should_exit: false,
scroll: 0,
last_tick: Instant::now(),
}
}
/// Run the app until the user exits.
fn run(mut self, mut terminal: DefaultTerminal) -> Result<()> {
while !self.should_exit {
terminal.draw(|frame| frame.render_widget(&self, frame.area()))?;
self.handle_events()?;
if self.last_tick.elapsed() >= Self::TICK_RATE {
self.on_tick();
self.last_tick = Instant::now();
}
}
Ok(())
}
/// Handle events from the terminal.
fn handle_events(&mut self) -> io::Result<()> {
let timeout = Self::TICK_RATE.saturating_sub(self.last_tick.elapsed());
while event::poll(timeout)? {
if let Event::Key(key) = event::read()? {
if key.kind == KeyEventKind::Press && key.code == KeyCode::Char('q') {
self.should_exit = true;
}
}
}
Ok(())
}
/// Update the app state on each tick.
fn on_tick(&mut self) {
self.scroll = (self.scroll + 1) % 10;
}
}
impl Widget for &App {
fn render(self, area: Rect, buf: &mut Buffer) {
let areas = Layout::vertical([Constraint::Max(9); 4]).split(area);
Paragraph::new(create_lines(area))
.block(title_block("Default alignment (Left), no wrap"))
.gray()
.render(areas[0], buf);
Paragraph::new(create_lines(area))
.block(title_block("Default alignment (Left), with wrap"))
.gray()
.wrap(Wrap { trim: true })
.render(areas[1], buf);
Paragraph::new(create_lines(area))
.block(title_block("Right alignment, with wrap"))
.gray()
.right_aligned()
.wrap(Wrap { trim: true })
.render(areas[2], buf);
Paragraph::new(create_lines(area))
.block(title_block("Center alignment, with wrap, with scroll"))
.gray()
.centered()
.wrap(Wrap { trim: true })
.scroll((self.scroll, 0))
.render(areas[3], buf);
}
}
/// Create a bordered block with a title.
fn title_block(title: &str) -> Block {
Block::bordered()
.gray()
.title(title.bold().into_centered_line())
}
/// Create some lines to display in the paragraph.
fn create_lines(area: Rect) -> Vec<Line<'static>> {
let short_line = "A long line to demonstrate line wrapping. ";
let long_line = short_line.repeat(usize::from(area.width) / short_line.len() + 4);
let mut styled_spans = vec![];
for span in [
"Styled".blue(),
"Spans".red().on_white(),
"Bold".bold(),
"Italic".italic(),
"Underlined".underlined(),
"Strikethrough".crossed_out(),
] {
styled_spans.push(span);
styled_spans.push(" ".into());
}
vec![
Line::raw("Unstyled Line"),
Line::raw("Styled Line").black().on_red().bold().italic(),
Line::from(styled_spans),
Line::from(long_line.green().italic()),
Line::from_iter([
"Masked text: ".into(),
Span::styled(Masked::new("my secret password", '*'), Color::Red),
]),
]
}
|
