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
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
|
//! # [Ratatui] Layout 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 itertools::Itertools;
use ratatui::{
crossterm::event::{self, Event, KeyCode, KeyEventKind},
layout::{
Constraint::{self, Length, Max, Min, Percentage, Ratio},
Layout, Rect,
},
style::{Color, Style, Stylize},
text::Line,
widgets::{Block, Paragraph},
DefaultTerminal, Frame,
};
fn main() -> color_eyre::Result<()> {
color_eyre::install()?;
let terminal = ratatui::init();
let app_result = run(terminal);
ratatui::restore();
app_result
}
fn run(mut terminal: DefaultTerminal) -> color_eyre::Result<()> {
loop {
terminal.draw(draw)?;
if let Event::Key(key) = event::read()? {
if key.kind == KeyEventKind::Press && key.code == KeyCode::Char('q') {
break Ok(());
}
}
}
}
#[allow(clippy::too_many_lines)]
fn draw(frame: &mut Frame) {
let vertical = Layout::vertical([
Length(4), // text
Length(50), // examples
Min(0), // fills remaining space
]);
let [text_area, examples_area, _] = vertical.areas(frame.area());
// title
frame.render_widget(
Paragraph::new(vec![
Line::from("Horizontal Layout Example. Press q to quit".dark_gray()).centered(),
Line::from("Each line has 2 constraints, plus Min(0) to fill the remaining space."),
Line::from("E.g. the second line of the Len/Min box is [Length(2), Min(2), Min(0)]"),
Line::from("Note: constraint labels that don't fit are truncated"),
]),
text_area,
);
let example_rows = Layout::vertical([
Length(9),
Length(9),
Length(9),
Length(9),
Length(9),
Min(0), // fills remaining space
])
.split(examples_area);
let example_areas = example_rows.iter().flat_map(|area| {
Layout::horizontal([
Length(14),
Length(14),
Length(14),
Length(14),
Length(14),
Min(0), // fills remaining space
])
.split(*area)
.iter()
.copied()
.take(5) // ignore Min(0)
.collect_vec()
});
// the examples are a cartesian product of the following constraints
// e.g. Len/Len, Len/Min, Len/Max, Len/Perc, Len/Ratio, Min/Len, Min/Min, ...
let examples = [
(
"Len",
[
Length(0),
Length(2),
Length(3),
Length(6),
Length(10),
Length(15),
],
),
("Min", [Min(0), Min(2), Min(3), Min(6), Min(10), Min(15)]),
("Max", [Max(0), Max(2), Max(3), Max(6), Max(10), Max(15)]),
(
"Perc",
[
Percentage(0),
Percentage(25),
Percentage(50),
Percentage(75),
Percentage(100),
Percentage(150),
],
),
(
"Ratio",
[
Ratio(0, 4),
Ratio(1, 4),
Ratio(2, 4),
Ratio(3, 4),
Ratio(4, 4),
Ratio(6, 4),
],
),
];
for ((a, b), area) in examples
.iter()
.cartesian_product(examples.iter())
.zip(example_areas)
{
let (name_a, examples_a) = a;
let (name_b, examples_b) = b;
let constraints = examples_a.iter().copied().zip(examples_b.iter().copied());
render_example_combination(frame, area, &format!("{name_a}/{name_b}"), constraints);
}
}
/// Renders a single example box
fn render_example_combination(
frame: &mut Frame,
area: Rect,
title: &str,
constraints: impl ExactSizeIterator<Item = (Constraint, Constraint)>,
) {
let block = Block::bordered()
.title(title.gray())
.style(Style::reset())
.border_style(Style::default().fg(Color::DarkGray));
let inner = block.inner(area);
frame.render_widget(block, area);
let layout = Layout::vertical(vec![Length(1); constraints.len() + 1]).split(inner);
for ((a, b), &area) in constraints.into_iter().zip(layout.iter()) {
render_single_example(frame, area, vec![a, b, Min(0)]);
}
// This is to make it easy to visually see the alignment of the examples
// with the constraints.
frame.render_widget(Paragraph::new("123456789012"), layout[6]);
}
/// Renders a single example line
fn render_single_example(frame: &mut Frame, area: Rect, constraints: Vec<Constraint>) {
let red = Paragraph::new(constraint_label(constraints[0])).on_red();
let blue = Paragraph::new(constraint_label(constraints[1])).on_blue();
let green = Paragraph::new("ยท".repeat(12)).on_green();
let horizontal = Layout::horizontal(constraints);
let [r, b, g] = horizontal.areas(area);
frame.render_widget(red, r);
frame.render_widget(blue, b);
frame.render_widget(green, g);
}
fn constraint_label(constraint: Constraint) -> String {
match constraint {
Constraint::Ratio(a, b) => format!("{a}:{b}"),
Constraint::Length(n)
| Constraint::Min(n)
| Constraint::Max(n)
| Constraint::Percentage(n)
| Constraint::Fill(n) => format!("{n}"),
}
}
|
