mirror of
https://github.com/bevyengine/bevy
synced 2024-11-28 15:40:21 +00:00
d454db8e58
# Objective
- Rename `Pickable` to `PickingBehavior` to counter the easily-made
assumption that the component is required. It is optional
- Fix and clarify documentation
- The docs in `crates/bevy_ui/src/picking_backend.rs` were incorrect
about the necessity of `Pickable`
- Plus two minor code quality changes in this commit
(7c2e75f48d)
Closes #15632
370 lines
16 KiB
Rust
370 lines
16 KiB
Rust
//! This example illustrates the various features of Bevy UI.
|
|
|
|
use bevy::{
|
|
a11y::{
|
|
accesskit::{NodeBuilder, Role},
|
|
AccessibilityNode,
|
|
},
|
|
color::palettes::basic::LIME,
|
|
input::mouse::{MouseScrollUnit, MouseWheel},
|
|
picking::focus::HoverMap,
|
|
prelude::*,
|
|
winit::WinitSettings,
|
|
};
|
|
|
|
fn main() {
|
|
let mut app = App::new();
|
|
app.add_plugins(DefaultPlugins)
|
|
// Only run the app when there is user input. This will significantly reduce CPU/GPU use.
|
|
.insert_resource(WinitSettings::desktop_app())
|
|
.add_systems(Startup, setup)
|
|
.add_systems(Update, update_scroll_position);
|
|
|
|
#[cfg(feature = "bevy_dev_tools")]
|
|
{
|
|
app.add_plugins(bevy::dev_tools::ui_debug_overlay::DebugUiPlugin)
|
|
.add_systems(Update, toggle_overlay);
|
|
}
|
|
|
|
app.run();
|
|
}
|
|
|
|
fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
|
|
// Camera
|
|
commands.spawn((Camera2d, IsDefaultUiCamera));
|
|
|
|
// root node
|
|
commands
|
|
.spawn(NodeBundle {
|
|
style: Style {
|
|
width: Val::Percent(100.0),
|
|
height: Val::Percent(100.0),
|
|
justify_content: JustifyContent::SpaceBetween,
|
|
..default()
|
|
},
|
|
..default()
|
|
})
|
|
.insert(PickingBehavior::IGNORE)
|
|
.with_children(|parent| {
|
|
// left vertical fill (border)
|
|
parent
|
|
.spawn(NodeBundle {
|
|
style: Style {
|
|
width: Val::Px(200.),
|
|
border: UiRect::all(Val::Px(2.)),
|
|
..default()
|
|
},
|
|
background_color: Color::srgb(0.65, 0.65, 0.65).into(),
|
|
..default()
|
|
})
|
|
.with_children(|parent| {
|
|
// left vertical fill (content)
|
|
parent
|
|
.spawn(NodeBundle {
|
|
style: Style {
|
|
width: Val::Percent(100.),
|
|
flex_direction: FlexDirection::Column,
|
|
padding: UiRect::all(Val::Px(5.)),
|
|
row_gap: Val::Px(5.),
|
|
..default()
|
|
},
|
|
background_color: Color::srgb(0.15, 0.15, 0.15).into(),
|
|
..default()
|
|
})
|
|
.with_children(|parent| {
|
|
// text
|
|
parent.spawn((
|
|
TextBundle::from_section(
|
|
"Text Example",
|
|
TextStyle {
|
|
font: asset_server.load("fonts/FiraSans-Bold.ttf"),
|
|
font_size: 25.0,
|
|
..default()
|
|
},
|
|
),
|
|
// Because this is a distinct label widget and
|
|
// not button/list item text, this is necessary
|
|
// for accessibility to treat the text accordingly.
|
|
Label,
|
|
));
|
|
|
|
#[cfg(feature = "bevy_dev_tools")]
|
|
// Debug overlay text
|
|
parent.spawn((
|
|
TextBundle::from_section(
|
|
"Press Space to enable debug outlines.",
|
|
TextStyle {
|
|
font: asset_server.load("fonts/FiraSans-Bold.ttf"),
|
|
..default()
|
|
},
|
|
),
|
|
Label,
|
|
));
|
|
|
|
#[cfg(not(feature = "bevy_dev_tools"))]
|
|
parent.spawn((
|
|
TextBundle::from_section(
|
|
"Try enabling feature \"bevy_dev_tools\".",
|
|
TextStyle {
|
|
font: asset_server.load("fonts/FiraSans-Bold.ttf"),
|
|
..default()
|
|
},
|
|
),
|
|
Label,
|
|
));
|
|
});
|
|
});
|
|
// right vertical fill
|
|
parent
|
|
.spawn(NodeBundle {
|
|
style: Style {
|
|
flex_direction: FlexDirection::Column,
|
|
justify_content: JustifyContent::Center,
|
|
align_items: AlignItems::Center,
|
|
width: Val::Px(200.),
|
|
..default()
|
|
},
|
|
..default()
|
|
})
|
|
.with_children(|parent| {
|
|
// Title
|
|
parent.spawn((
|
|
TextBundle::from_section(
|
|
"Scrolling list",
|
|
TextStyle {
|
|
font: asset_server.load("fonts/FiraSans-Bold.ttf"),
|
|
font_size: 21.,
|
|
..default()
|
|
},
|
|
),
|
|
Label,
|
|
));
|
|
// Scrolling list
|
|
parent
|
|
.spawn(NodeBundle {
|
|
style: Style {
|
|
flex_direction: FlexDirection::Column,
|
|
align_self: AlignSelf::Stretch,
|
|
height: Val::Percent(50.),
|
|
overflow: Overflow::scroll_y(),
|
|
..default()
|
|
},
|
|
background_color: Color::srgb(0.10, 0.10, 0.10).into(),
|
|
..default()
|
|
})
|
|
.with_children(|parent| {
|
|
// List items
|
|
for i in 0..25 {
|
|
parent
|
|
.spawn((
|
|
TextBundle::from_section(
|
|
format!("Item {i}"),
|
|
TextStyle {
|
|
font: asset_server.load("fonts/FiraSans-Bold.ttf"),
|
|
..default()
|
|
},
|
|
),
|
|
Label,
|
|
AccessibilityNode(NodeBuilder::new(Role::ListItem)),
|
|
))
|
|
.insert(PickingBehavior {
|
|
should_block_lower: false,
|
|
..default()
|
|
});
|
|
}
|
|
});
|
|
});
|
|
|
|
parent
|
|
.spawn(NodeBundle {
|
|
style: Style {
|
|
width: Val::Px(200.0),
|
|
height: Val::Px(200.0),
|
|
position_type: PositionType::Absolute,
|
|
left: Val::Px(210.),
|
|
bottom: Val::Px(10.),
|
|
border: UiRect::all(Val::Px(20.)),
|
|
..default()
|
|
},
|
|
border_color: LIME.into(),
|
|
background_color: Color::srgb(0.4, 0.4, 1.).into(),
|
|
..default()
|
|
})
|
|
.with_children(|parent| {
|
|
parent.spawn(NodeBundle {
|
|
style: Style {
|
|
width: Val::Percent(100.0),
|
|
height: Val::Percent(100.0),
|
|
..default()
|
|
},
|
|
background_color: Color::srgb(0.8, 0.8, 1.).into(),
|
|
..default()
|
|
});
|
|
});
|
|
// render order test: reddest in the back, whitest in the front (flex center)
|
|
parent
|
|
.spawn(NodeBundle {
|
|
style: Style {
|
|
width: Val::Percent(100.0),
|
|
height: Val::Percent(100.0),
|
|
position_type: PositionType::Absolute,
|
|
align_items: AlignItems::Center,
|
|
justify_content: JustifyContent::Center,
|
|
..default()
|
|
},
|
|
..default()
|
|
})
|
|
.insert(PickingBehavior::IGNORE)
|
|
.with_children(|parent| {
|
|
parent
|
|
.spawn(NodeBundle {
|
|
style: Style {
|
|
width: Val::Px(100.0),
|
|
height: Val::Px(100.0),
|
|
..default()
|
|
},
|
|
background_color: Color::srgb(1.0, 0.0, 0.).into(),
|
|
..default()
|
|
})
|
|
.with_children(|parent| {
|
|
parent.spawn(NodeBundle {
|
|
style: Style {
|
|
// Take the size of the parent node.
|
|
width: Val::Percent(100.0),
|
|
height: Val::Percent(100.0),
|
|
position_type: PositionType::Absolute,
|
|
left: Val::Px(20.),
|
|
bottom: Val::Px(20.),
|
|
..default()
|
|
},
|
|
background_color: Color::srgb(1.0, 0.3, 0.3).into(),
|
|
..default()
|
|
});
|
|
parent.spawn(NodeBundle {
|
|
style: Style {
|
|
width: Val::Percent(100.0),
|
|
height: Val::Percent(100.0),
|
|
position_type: PositionType::Absolute,
|
|
left: Val::Px(40.),
|
|
bottom: Val::Px(40.),
|
|
..default()
|
|
},
|
|
background_color: Color::srgb(1.0, 0.5, 0.5).into(),
|
|
..default()
|
|
});
|
|
parent.spawn(NodeBundle {
|
|
style: Style {
|
|
width: Val::Percent(100.0),
|
|
height: Val::Percent(100.0),
|
|
position_type: PositionType::Absolute,
|
|
left: Val::Px(60.),
|
|
bottom: Val::Px(60.),
|
|
..default()
|
|
},
|
|
background_color: Color::srgb(1.0, 0.7, 0.7).into(),
|
|
..default()
|
|
});
|
|
// alpha test
|
|
parent.spawn(NodeBundle {
|
|
style: Style {
|
|
width: Val::Percent(100.0),
|
|
height: Val::Percent(100.0),
|
|
position_type: PositionType::Absolute,
|
|
left: Val::Px(80.),
|
|
bottom: Val::Px(80.),
|
|
..default()
|
|
},
|
|
background_color: Color::srgba(1.0, 0.9, 0.9, 0.4).into(),
|
|
..default()
|
|
});
|
|
});
|
|
});
|
|
// bevy logo (flex center)
|
|
parent
|
|
.spawn(NodeBundle {
|
|
style: Style {
|
|
width: Val::Percent(100.0),
|
|
position_type: PositionType::Absolute,
|
|
justify_content: JustifyContent::Center,
|
|
align_items: AlignItems::FlexStart,
|
|
..default()
|
|
},
|
|
..default()
|
|
})
|
|
.with_children(|parent| {
|
|
// bevy logo (image)
|
|
// A `NodeBundle` is used to display the logo the image as an `ImageBundle` can't automatically
|
|
// size itself with a child node present.
|
|
parent
|
|
.spawn((
|
|
NodeBundle {
|
|
style: Style {
|
|
width: Val::Px(500.0),
|
|
height: Val::Px(125.0),
|
|
margin: UiRect::top(Val::VMin(5.)),
|
|
..default()
|
|
},
|
|
..default()
|
|
},
|
|
UiImage::new(asset_server.load("branding/bevy_logo_dark_big.png")),
|
|
))
|
|
.with_children(|parent| {
|
|
// alt text
|
|
// This UI node takes up no space in the layout and the `Text` component is used by the accessibility module
|
|
// and is not rendered.
|
|
parent.spawn((
|
|
NodeBundle {
|
|
style: Style {
|
|
display: Display::None,
|
|
..Default::default()
|
|
},
|
|
..Default::default()
|
|
},
|
|
Text::from_section("Bevy logo", TextStyle::default()),
|
|
));
|
|
});
|
|
});
|
|
});
|
|
}
|
|
|
|
#[cfg(feature = "bevy_dev_tools")]
|
|
// The system that will enable/disable the debug outlines around the nodes
|
|
fn toggle_overlay(
|
|
input: Res<ButtonInput<KeyCode>>,
|
|
mut options: ResMut<bevy::dev_tools::ui_debug_overlay::UiDebugOptions>,
|
|
) {
|
|
info_once!("The debug outlines are enabled, press Space to turn them on/off");
|
|
if input.just_pressed(KeyCode::Space) {
|
|
// The toggle method will enable the debug_overlay if disabled and disable if enabled
|
|
options.toggle();
|
|
}
|
|
}
|
|
|
|
/// Updates the scroll position of scrollable nodes in response to mouse input
|
|
pub fn update_scroll_position(
|
|
mut mouse_wheel_events: EventReader<MouseWheel>,
|
|
hover_map: Res<HoverMap>,
|
|
mut scrolled_node_query: Query<&mut ScrollPosition>,
|
|
keyboard_input: Res<ButtonInput<KeyCode>>,
|
|
) {
|
|
for mouse_wheel_event in mouse_wheel_events.read() {
|
|
let (mut dx, mut dy) = match mouse_wheel_event.unit {
|
|
MouseScrollUnit::Line => (mouse_wheel_event.x * 20., mouse_wheel_event.y * 20.),
|
|
MouseScrollUnit::Pixel => (mouse_wheel_event.x, mouse_wheel_event.y),
|
|
};
|
|
|
|
if keyboard_input.pressed(KeyCode::ShiftLeft) || keyboard_input.pressed(KeyCode::ShiftRight)
|
|
{
|
|
std::mem::swap(&mut dx, &mut dy);
|
|
}
|
|
|
|
for (_pointer, pointer_map) in hover_map.iter() {
|
|
for (entity, _hit) in pointer_map.iter() {
|
|
if let Ok(mut scroll_position) = scrolled_node_query.get_mut(*entity) {
|
|
scroll_position.offset_x -= dx;
|
|
scroll_position.offset_y -= dy;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|