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use crate::canvas::Canvas;
use crate::draw::{Draw, DrawResult};
use crate::event::Event;
use crate::widget::{Rectangle, Widget};
pub struct Stack<'a, Message = ()> {
inner: Vec<Box<dyn Widget<Message> + 'a>>,
}
impl<'a, Message> Stack<'a, Message> {
pub fn new() -> Self {
Self { inner: vec![] }
}
pub fn top(mut self, widget: impl Widget<Message> + 'a) -> Self {
self.inner.push(Box::new(widget));
self
}
pub fn bottom(mut self, widget: impl Widget<Message> + 'a) -> Self {
self.inner.insert(0, Box::new(widget));
self
}
}
impl<'a, Message> Draw for Stack<'a, Message> {
fn draw(&self, canvas: &mut dyn Canvas) -> DrawResult<()> {
for widget in self.inner.iter() {
widget.draw(canvas)?
}
Ok(())
}
}
impl<'a, Message> Widget<Message> for Stack<'a, Message> {
fn size_hint(&self) -> (Option<usize>, Option<usize>) {
let width = self
.inner
.iter()
.map(|widget| widget.size_hint().0)
.max()
.unwrap_or(None);
let height = self
.inner
.iter()
.map(|widget| widget.size_hint().1)
.max()
.unwrap_or(None);
(width, height)
}
fn on_event(&self, event: Event, rect: Rectangle) -> Vec<Message> {
for widget in self.inner.iter().rev() {
let message = widget.on_event(event, rect);
if !message.is_empty() {
return message;
}
}
vec![]
}
}
#[cfg(test)]
#[allow(dead_code)]
mod test {
use super::*;
struct WinHint {
pub width_hint: Option<usize>,
pub height_hint: Option<usize>,
}
impl Draw for WinHint {
fn draw(&self, _canvas: &mut dyn Canvas) -> DrawResult<()> {
unimplemented!()
}
}
impl Widget for WinHint {
fn size_hint(&self) -> (Option<usize>, Option<usize>) {
(self.width_hint, self.height_hint)
}
}
#[test]
fn size_hint() {
let stack = Stack::new().top(WinHint {
width_hint: None,
height_hint: None,
});
assert_eq!((None, None), stack.size_hint());
let stack = Stack::new().top(WinHint {
width_hint: Some(1),
height_hint: Some(1),
});
assert_eq!((Some(1), Some(1)), stack.size_hint());
let stack = Stack::new()
.top(WinHint {
width_hint: Some(1),
height_hint: Some(2),
})
.top(WinHint {
width_hint: Some(2),
height_hint: Some(1),
});
assert_eq!((Some(2), Some(2)), stack.size_hint());
let stack = Stack::new()
.top(WinHint {
width_hint: None,
height_hint: None,
})
.top(WinHint {
width_hint: Some(2),
height_hint: Some(1),
});
assert_eq!((Some(2), Some(1)), stack.size_hint());
}
}