1use crate::{Bounds, Element, IntoElement, Pixels, StyleRefinement, Styled, WindowContext};
 2
 3pub fn canvas(callback: impl 'static + FnOnce(Bounds<Pixels>, &mut WindowContext)) -> Canvas {
 4    Canvas {
 5        paint_callback: Box::new(callback),
 6        style: Default::default(),
 7    }
 8}
 9
10pub struct Canvas {
11    paint_callback: Box<dyn FnOnce(Bounds<Pixels>, &mut WindowContext)>,
12    style: StyleRefinement,
13}
14
15impl IntoElement for Canvas {
16    type Element = Self;
17
18    fn element_id(&self) -> Option<crate::ElementId> {
19        None
20    }
21
22    fn into_element(self) -> Self::Element {
23        self
24    }
25}
26
27impl Element for Canvas {
28    type State = ();
29
30    fn layout(
31        &mut self,
32        _: Option<Self::State>,
33        cx: &mut WindowContext,
34    ) -> (crate::LayoutId, Self::State) {
35        let layout_id = cx.request_layout(&self.style.clone().into(), []);
36        (layout_id, ())
37    }
38
39    fn paint(self, bounds: Bounds<Pixels>, _: &mut (), cx: &mut WindowContext) {
40        (self.paint_callback)(bounds, cx)
41    }
42}
43
44impl Styled for Canvas {
45    fn style(&mut self) -> &mut crate::StyleRefinement {
46        &mut self.style
47    }
48}