extern crate alloc;
use crate::core::reactive::{Computed, Signal};
use crate::prelude::*;
#[compose]
pub fn build_widgets() {
let n = Signal::new(2i32);
let squared = {
let n = n.clone();
Computed::new(move || n.get() * n.get())
};
let (inc, label) = (n.clone(), squared.clone());
ui! {
Column (
grow: 1.0,
align: AlignItems::Center,
justify: JustifyContent::Center,
padding: Padding::all(16)
) {
View (text: ${ alloc::format!("n^2 = {}", label.get()) }, height: 40)
View (
bg_color: Color::rgb(63, 185, 80),
width: 120,
height: 40,
border_radius: 8,
text: "n + 1"
) on Tap { inc.update(|v| *v += 1); }
}
};
}
#[cfg(feature = "std")]
pub fn setup_app<B, F>(app: &mut App<B, F>, parent: Entity)
where
B: Surface,
F: RendererFactory<B>,
{
use crate::app::plugins::StdInstantClockPlugin;
app.add_plugin(StdInstantClockPlugin);
app.compose(parent, build_widgets);
}
#[cfg(test)]
mod tests {
use super::*;
use crate::core::reactive::flush_signal_dirty;
use crate::input::event::GestureHandler;
use crate::input::event::gesture::GestureEvent;
use crate::ui::Children;
use crate::ui::IdMap;
use crate::ui::UiScope;
use crate::ui::widgets::text::Text;
fn label_text(world: &World, label: Entity) -> alloc::string::String {
let t = world.get::<Text>(label).expect("label has Text");
t.resolve(world).into_owned()
}
#[test]
fn computed_label_tracks_source() {
let mut world = World::new();
world.insert_resource(IdMap::new());
let parent = WidgetBuilder::new(&mut world).id();
let mut cx = UiScope::new(&mut world, parent);
build_widgets(&mut cx);
let col = world.get::<Children>(parent).unwrap().0[0];
let label = world.get::<Children>(col).unwrap().0[0];
let btn = world.get::<Children>(col).unwrap().0[1];
assert_eq!(label_text(&world, label), "n^2 = 4");
let tap = GestureEvent::Tap {
x: Fixed::ZERO,
y: Fixed::ZERO,
target: btn,
};
GestureHandler::trigger(&mut world, btn, &tap);
flush_signal_dirty(&mut world);
assert_eq!(label_text(&world, label), "n^2 = 9");
}
}