mirror of
https://github.com/bevyengine/bevy
synced 2024-11-26 06:30:19 +00:00
309 lines
13 KiB
Rust
309 lines
13 KiB
Rust
//! This example illustrates the various features of Bevy UI.
|
|
|
|
use bevy::{
|
|
a11y::{
|
|
accesskit::{NodeBuilder, Role},
|
|
AccessibilityNode,
|
|
},
|
|
input::mouse::{MouseScrollUnit, MouseWheel},
|
|
prelude::*,
|
|
winit::WinitSettings,
|
|
};
|
|
|
|
fn main() {
|
|
App::new()
|
|
.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, mouse_scroll)
|
|
.run();
|
|
}
|
|
|
|
fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
|
|
// Camera
|
|
commands.spawn(Camera2dBundle::default());
|
|
|
|
// root node
|
|
commands
|
|
.spawn(NodeBundle {
|
|
style: Style {
|
|
size: Size::all(Val::Percent(100.)),
|
|
justify_content: JustifyContent::SpaceBetween,
|
|
..default()
|
|
},
|
|
..default()
|
|
})
|
|
.with_children(|parent| {
|
|
// left vertical fill (border)
|
|
parent
|
|
.spawn(NodeBundle {
|
|
style: Style {
|
|
size: Size::width(Val::Px(200.)),
|
|
border: UiRect::all(Val::Px(2.)),
|
|
..default()
|
|
},
|
|
background_color: Color::rgb(0.65, 0.65, 0.65).into(),
|
|
..default()
|
|
})
|
|
.with_children(|parent| {
|
|
// left vertical fill (content)
|
|
parent
|
|
.spawn(NodeBundle {
|
|
style: Style {
|
|
size: Size::width(Val::Percent(100.)),
|
|
..default()
|
|
},
|
|
background_color: Color::rgb(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: 30.0,
|
|
color: Color::WHITE,
|
|
},
|
|
)
|
|
.with_style(Style {
|
|
margin: UiRect::all(Val::Px(5.)),
|
|
..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,
|
|
));
|
|
});
|
|
});
|
|
// right vertical fill
|
|
parent
|
|
.spawn(NodeBundle {
|
|
style: Style {
|
|
flex_direction: FlexDirection::Column,
|
|
justify_content: JustifyContent::Center,
|
|
align_items: AlignItems::Center,
|
|
size: Size::width(Val::Px(200.)),
|
|
..default()
|
|
},
|
|
background_color: Color::rgb(0.15, 0.15, 0.15).into(),
|
|
..default()
|
|
})
|
|
.with_children(|parent| {
|
|
// Title
|
|
parent.spawn((
|
|
TextBundle::from_section(
|
|
"Scrolling list",
|
|
TextStyle {
|
|
font: asset_server.load("fonts/FiraSans-Bold.ttf"),
|
|
font_size: 25.,
|
|
color: Color::WHITE,
|
|
},
|
|
),
|
|
Label,
|
|
));
|
|
// List with hidden overflow
|
|
parent
|
|
.spawn(NodeBundle {
|
|
style: Style {
|
|
flex_direction: FlexDirection::Column,
|
|
align_self: AlignSelf::Stretch,
|
|
size: Size::height(Val::Percent(50.)),
|
|
overflow: Overflow::Hidden,
|
|
..default()
|
|
},
|
|
background_color: Color::rgb(0.10, 0.10, 0.10).into(),
|
|
..default()
|
|
})
|
|
.with_children(|parent| {
|
|
// Moving panel
|
|
parent
|
|
.spawn((
|
|
NodeBundle {
|
|
style: Style {
|
|
flex_direction: FlexDirection::Column,
|
|
align_items: AlignItems::Center,
|
|
..default()
|
|
},
|
|
..default()
|
|
},
|
|
ScrollingList::default(),
|
|
AccessibilityNode(NodeBuilder::new(Role::List)),
|
|
))
|
|
.with_children(|parent| {
|
|
// List items
|
|
for i in 0..30 {
|
|
parent.spawn((
|
|
TextBundle::from_section(
|
|
format!("Item {i}"),
|
|
TextStyle {
|
|
font: asset_server
|
|
.load("fonts/FiraSans-Bold.ttf"),
|
|
font_size: 20.,
|
|
color: Color::WHITE,
|
|
},
|
|
),
|
|
Label,
|
|
AccessibilityNode(NodeBuilder::new(Role::ListItem)),
|
|
));
|
|
}
|
|
});
|
|
});
|
|
});
|
|
parent
|
|
.spawn(NodeBundle {
|
|
style: Style {
|
|
size: Size::all(Val::Px(200.)),
|
|
position_type: PositionType::Absolute,
|
|
left: Val::Px(210.),
|
|
bottom: Val::Px(10.),
|
|
border: UiRect::all(Val::Px(20.)),
|
|
..default()
|
|
},
|
|
background_color: Color::rgb(0.4, 0.4, 1.).into(),
|
|
..default()
|
|
})
|
|
.with_children(|parent| {
|
|
parent.spawn(NodeBundle {
|
|
style: Style {
|
|
size: Size::all(Val::Percent(100.)),
|
|
..default()
|
|
},
|
|
background_color: Color::rgb(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 {
|
|
size: Size::all(Val::Percent(100.)),
|
|
position_type: PositionType::Absolute,
|
|
align_items: AlignItems::Center,
|
|
justify_content: JustifyContent::Center,
|
|
..default()
|
|
},
|
|
..default()
|
|
})
|
|
.with_children(|parent| {
|
|
parent
|
|
.spawn(NodeBundle {
|
|
style: Style {
|
|
size: Size::all(Val::Px(100.)),
|
|
..default()
|
|
},
|
|
background_color: Color::rgb(1.0, 0.0, 0.).into(),
|
|
..default()
|
|
})
|
|
.with_children(|parent| {
|
|
parent.spawn(NodeBundle {
|
|
style: Style {
|
|
// Take the size of the parent node.
|
|
size: Size::all(Val::Percent(100.)),
|
|
position_type: PositionType::Absolute,
|
|
left: Val::Px(20.),
|
|
bottom: Val::Px(20.),
|
|
..default()
|
|
},
|
|
background_color: Color::rgb(1.0, 0.3, 0.3).into(),
|
|
..default()
|
|
});
|
|
parent.spawn(NodeBundle {
|
|
style: Style {
|
|
size: Size::all(Val::Percent(100.)),
|
|
position_type: PositionType::Absolute,
|
|
left: Val::Px(40.),
|
|
bottom: Val::Px(40.),
|
|
..default()
|
|
},
|
|
background_color: Color::rgb(1.0, 0.5, 0.5).into(),
|
|
..default()
|
|
});
|
|
parent.spawn(NodeBundle {
|
|
style: Style {
|
|
size: Size::all(Val::Percent(100.)),
|
|
position_type: PositionType::Absolute,
|
|
left: Val::Px(60.),
|
|
bottom: Val::Px(60.),
|
|
..default()
|
|
},
|
|
background_color: Color::rgb(1.0, 0.7, 0.7).into(),
|
|
..default()
|
|
});
|
|
// alpha test
|
|
parent.spawn(NodeBundle {
|
|
style: Style {
|
|
size: Size::all(Val::Percent(100.)),
|
|
position_type: PositionType::Absolute,
|
|
left: Val::Px(80.),
|
|
bottom: Val::Px(80.),
|
|
..default()
|
|
},
|
|
background_color: Color::rgba(1.0, 0.9, 0.9, 0.4).into(),
|
|
..default()
|
|
});
|
|
});
|
|
});
|
|
// bevy logo (flex center)
|
|
parent
|
|
.spawn(NodeBundle {
|
|
style: Style {
|
|
size: Size::width(Val::Percent(100.)),
|
|
position_type: PositionType::Absolute,
|
|
justify_content: JustifyContent::Center,
|
|
align_items: AlignItems::FlexStart,
|
|
..default()
|
|
},
|
|
..default()
|
|
})
|
|
.with_children(|parent| {
|
|
// bevy logo (image)
|
|
|
|
parent
|
|
.spawn(ImageBundle {
|
|
style: Style {
|
|
size: Size::width(Val::Px(500.0)),
|
|
..default()
|
|
},
|
|
..default()
|
|
})
|
|
.with_children(|parent| {
|
|
// alt text
|
|
parent
|
|
.spawn(TextBundle::from_section("Bevy logo", TextStyle::default()));
|
|
});
|
|
});
|
|
});
|
|
}
|
|
|
|
#[derive(Component, Default)]
|
|
struct ScrollingList {
|
|
position: f32,
|
|
}
|
|
|
|
fn mouse_scroll(
|
|
mut mouse_wheel_events: EventReader<MouseWheel>,
|
|
mut query_list: Query<(&mut ScrollingList, &mut Style, &Parent, &Node)>,
|
|
query_node: Query<&Node>,
|
|
) {
|
|
for mouse_wheel_event in mouse_wheel_events.iter() {
|
|
for (mut scrolling_list, mut style, parent, list_node) in &mut query_list {
|
|
let items_height = list_node.size().y;
|
|
let container_height = query_node.get(parent.get()).unwrap().size().y;
|
|
|
|
let max_scroll = (items_height - container_height).max(0.);
|
|
|
|
let dy = match mouse_wheel_event.unit {
|
|
MouseScrollUnit::Line => mouse_wheel_event.y * 20.,
|
|
MouseScrollUnit::Pixel => mouse_wheel_event.y,
|
|
};
|
|
|
|
scrolling_list.position += dy;
|
|
scrolling_list.position = scrolling_list.position.clamp(-max_scroll, 0.);
|
|
style.top = Val::Px(scrolling_list.position);
|
|
}
|
|
}
|
|
}
|