bevy/examples/ui/overflow.rs
UkoeHB c2c19e5ae4
Text rework (#15591)
**Ready for review. Examples migration progress: 100%.**

# Objective

- Implement https://github.com/bevyengine/bevy/discussions/15014

## Solution

This implements [cart's
proposal](https://github.com/bevyengine/bevy/discussions/15014#discussioncomment-10574459)
faithfully except for one change. I separated `TextSpan` from
`TextSpan2d` because `TextSpan` needs to require the `GhostNode`
component, which is a `bevy_ui` component only usable by UI.

Extra changes:
- Added `EntityCommands::commands_mut` that returns a mutable reference.
This is a blocker for extension methods that return something other than
`self`. Note that `sickle_ui`'s `UiBuilder::commands` returns a mutable
reference for this reason.

## Testing

- [x] Text examples all work.

---

## Showcase

TODO: showcase-worthy

## Migration Guide

TODO: very breaking

### Accessing text spans by index

Text sections are now text sections on different entities in a
hierarchy, Use the new `TextReader` and `TextWriter` system parameters
to access spans by index.

Before:
```rust
fn refresh_text(mut query: Query<&mut Text, With<TimeText>>, time: Res<Time>) {
    let text = query.single_mut();
    text.sections[1].value = format_time(time.elapsed());
}
```

After:
```rust
fn refresh_text(
    query: Query<Entity, With<TimeText>>,
    mut writer: UiTextWriter,
    time: Res<Time>
) {
    let entity = query.single();
    *writer.text(entity, 1) = format_time(time.elapsed());
}
```

### Iterating text spans

Text spans are now entities in a hierarchy, so the new `UiTextReader`
and `UiTextWriter` system parameters provide ways to iterate that
hierarchy. The `UiTextReader::iter` method will give you a normal
iterator over spans, and `UiTextWriter::for_each` lets you visit each of
the spans.

---------

Co-authored-by: ickshonpe <david.curthoys@googlemail.com>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2024-10-09 18:35:36 +00:00

116 lines
4.7 KiB
Rust

//! Simple example demonstrating overflow behavior.
use bevy::{color::palettes::css::*, 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, update_outlines)
.run();
}
fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
commands.spawn(Camera2d);
let text_style = TextStyle::default();
let image = asset_server.load("branding/icon.png");
commands
.spawn(NodeBundle {
style: Style {
width: Val::Percent(100.),
height: Val::Percent(100.),
align_items: AlignItems::Center,
justify_content: JustifyContent::Center,
..Default::default()
},
background_color: ANTIQUE_WHITE.into(),
..Default::default()
})
.with_children(|parent| {
for overflow in [
Overflow::visible(),
Overflow::clip_x(),
Overflow::clip_y(),
Overflow::clip(),
] {
parent
.spawn(NodeBundle {
style: Style {
flex_direction: FlexDirection::Column,
align_items: AlignItems::Center,
margin: UiRect::horizontal(Val::Px(25.)),
..Default::default()
},
..Default::default()
})
.with_children(|parent| {
let label = format!("{overflow:#?}");
parent
.spawn(NodeBundle {
style: Style {
padding: UiRect::all(Val::Px(10.)),
margin: UiRect::bottom(Val::Px(25.)),
..Default::default()
},
background_color: Color::srgb(0.25, 0.25, 0.25).into(),
..Default::default()
})
.with_children(|parent| {
parent.spawn((Text::new(label), text_style.clone()));
});
parent
.spawn(NodeBundle {
style: Style {
width: Val::Px(100.),
height: Val::Px(100.),
padding: UiRect {
left: Val::Px(25.),
top: Val::Px(25.),
..Default::default()
},
overflow,
..Default::default()
},
background_color: GRAY.into(),
..Default::default()
})
.with_children(|parent| {
parent.spawn((
ImageBundle {
image: UiImage::new(image.clone()),
style: Style {
min_width: Val::Px(100.),
min_height: Val::Px(100.),
..Default::default()
},
..Default::default()
},
Interaction::default(),
Outline {
width: Val::Px(2.),
offset: Val::Px(2.),
color: Color::NONE,
},
));
});
});
}
});
}
fn update_outlines(mut outlines_query: Query<(&mut Outline, Ref<Interaction>)>) {
for (mut outline, interaction) in outlines_query.iter_mut() {
if interaction.is_changed() {
outline.color = match *interaction {
Interaction::Pressed => RED.into(),
Interaction::Hovered => WHITE.into(),
Interaction::None => Color::NONE,
};
}
}
}