Support Warning
WebGPU is currently only supported on Chrome starting with version 113, and only on desktop. If they don't work on your configuration, you can check the WebGL2 examples here.grid.rs:
//! Demonstrates how CSS Grid layout can be used to lay items out in a 2D grid
use bevy::{color::palettes::css::*, prelude::*};
fn main() {
App::new()
.add_plugins(DefaultPlugins.set(WindowPlugin {
primary_window: Some(Window {
resolution: [800., 600.].into(),
title: "Bevy CSS Grid Layout Example".to_string(),
..default()
}),
..default()
}))
.add_systems(Startup, spawn_layout)
.run();
}
fn spawn_layout(mut commands: Commands, asset_server: Res<AssetServer>) {
let font = asset_server.load("fonts/FiraSans-Bold.ttf");
commands.spawn(Camera2d);
// Top-level grid (app frame)
commands
.spawn((
Node {
// Use the CSS Grid algorithm for laying out this node
display: Display::Grid,
// Make node fill the entirety of its parent (in this case the window)
width: Val::Percent(100.0),
height: Val::Percent(100.0),
// Set the grid to have 2 columns with sizes [min-content, minmax(0, 1fr)]
// - The first column will size to the size of its contents
// - The second column will take up the remaining available space
grid_template_columns: vec![GridTrack::min_content(), GridTrack::flex(1.0)],
// Set the grid to have 3 rows with sizes [auto, minmax(0, 1fr), 20px]
// - The first row will size to the size of its contents
// - The second row take up remaining available space (after rows 1 and 3 have both been sized)
// - The third row will be exactly 20px high
grid_template_rows: vec![
GridTrack::auto(),
GridTrack::flex(1.0),
GridTrack::px(20.),
],
..default()
},
BackgroundColor(Color::WHITE),
))
.with_children(|builder| {
// Header
builder
.spawn(
Node {
display: Display::Grid,
// Make this node span two grid columns so that it takes up the entire top tow
grid_column: GridPlacement::span(2),
padding: UiRect::all(Val::Px(6.0)),
..default()
},
)
.with_children(|builder| {
spawn_nested_text_bundle(builder, font.clone(), "Bevy CSS Grid Layout Example");
});
// Main content grid (auto placed in row 2, column 1)
builder
.spawn((
Node {
// Make the height of the node fill its parent
height: Val::Percent(100.0),
// Make the grid have a 1:1 aspect ratio meaning it will scale as an exact square
// As the height is set explicitly, this means the width will adjust to match the height
aspect_ratio: Some(1.0),
// Use grid layout for this node
display: Display::Grid,
// Add 24px of padding around the grid
padding: UiRect::all(Val::Px(24.0)),
// Set the grid to have 4 columns all with sizes minmax(0, 1fr)
// This creates 4 exactly evenly sized columns
grid_template_columns: RepeatedGridTrack::flex(4, 1.0),
// Set the grid to have 4 rows all with sizes minmax(0, 1fr)
// This creates 4 exactly evenly sized rows
grid_template_rows: RepeatedGridTrack::flex(4, 1.0),
// Set a 12px gap/gutter between rows and columns
row_gap: Val::Px(12.0),
column_gap: Val::Px(12.0),
..default()
},
BackgroundColor(Color::srgb(0.25, 0.25, 0.25)),
))
.with_children(|builder| {
// Note there is no need to specify the position for each grid item. Grid items that are
// not given an explicit position will be automatically positioned into the next available
// grid cell. The order in which this is performed can be controlled using the grid_auto_flow
// style property.
item_rect(builder, ORANGE);
item_rect(builder, BISQUE);
item_rect(builder, BLUE);
item_rect(builder, CRIMSON);
item_rect(builder, AQUA);
item_rect(builder, ORANGE_RED);
item_rect(builder, DARK_GREEN);
item_rect(builder, FUCHSIA);
item_rect(builder, TEAL);
item_rect(builder, ALICE_BLUE);
item_rect(builder, CRIMSON);
item_rect(builder, ANTIQUE_WHITE);
item_rect(builder, YELLOW);
item_rect(builder, DEEP_PINK);
item_rect(builder, YELLOW_GREEN);
item_rect(builder, SALMON);
});
// Right side bar (auto placed in row 2, column 2)
builder
.spawn((
Node {
display: Display::Grid,
// Align content towards the start (top) in the vertical axis
align_items: AlignItems::Start,
// Align content towards the center in the horizontal axis
justify_items: JustifyItems::Center,
// Add 10px padding
padding: UiRect::all(Val::Px(10.)),
// Add an fr track to take up all the available space at the bottom of the column so that the text nodes
// can be top-aligned. Normally you'd use flexbox for this, but this is the CSS Grid example so we're using grid.
grid_template_rows: vec![GridTrack::auto(), GridTrack::auto(), GridTrack::fr(1.0)],
// Add a 10px gap between rows
row_gap: Val::Px(10.),
..default()
},
BackgroundColor(BLACK.into()),
))
.with_children(|builder| {
builder.spawn((Text::new("Sidebar"),
TextFont {
font: font.clone(),
..default()
},
));
builder.spawn((Text::new("A paragraph of text which ought to wrap nicely. A paragraph of text which ought to wrap nicely. A paragraph of text which ought to wrap nicely. A paragraph of text which ought to wrap nicely. A paragraph of text which ought to wrap nicely. A paragraph of text which ought to wrap nicely. A paragraph of text which ought to wrap nicely."),
TextFont {
font: font.clone(),
font_size: 13.0,
..default()
},
));
builder.spawn(Node::default());
});
// Footer / status bar
builder.spawn((
Node {
// Make this node span two grid column so that it takes up the entire bottom row
grid_column: GridPlacement::span(2),
..default()
},
BackgroundColor(WHITE.into()),
));
// Modal (absolutely positioned on top of content - currently hidden: to view it, change its visibility)
builder.spawn((
Node {
position_type: PositionType::Absolute,
margin: UiRect {
top: Val::Px(100.),
bottom: Val::Auto,
left: Val::Auto,
right: Val::Auto,
},
width: Val::Percent(60.),
height: Val::Px(300.),
max_width: Val::Px(600.),
..default()
},
Visibility::Hidden,
BackgroundColor(Color::WHITE.with_alpha(0.8)),
));
});
}
/// Create a colored rectangle node. The node has size as it is assumed that it will be
/// spawned as a child of a Grid container with `AlignItems::Stretch` and `JustifyItems::Stretch`
/// which will allow it to take its size from the size of the grid area it occupies.
fn item_rect(builder: &mut ChildBuilder, color: Srgba) {
builder
.spawn((
Node {
display: Display::Grid,
padding: UiRect::all(Val::Px(3.0)),
..default()
},
BackgroundColor(BLACK.into()),
))
.with_children(|builder| {
builder.spawn((Node::default(), BackgroundColor(color.into())));
});
}
fn spawn_nested_text_bundle(builder: &mut ChildBuilder, font: Handle<Font>, text: &str) {
builder.spawn((
Text::new(text),
TextFont { font, ..default() },
TextColor::BLACK,
));
}