119aa452b6
Now the Element trait is designed to be wrapped in a Lifecycle enum that gets placed inside an ElementBox. This allows the framework to store data on behalf of the Element implementation, such as sizes, bounds, and also implementation-specific LayoutState and PaintState types. This makes it easier to reason about which data is available in each Element method.
77 lines
1.8 KiB
Rust
77 lines
1.8 KiB
Rust
use crate::{
|
|
geometry::vector::Vector2F, AfterLayoutContext, Element, ElementBox, Event, EventContext,
|
|
LayoutContext, PaintContext, SizeConstraint,
|
|
};
|
|
|
|
pub struct Stack {
|
|
children: Vec<ElementBox>,
|
|
}
|
|
|
|
impl Stack {
|
|
pub fn new() -> Self {
|
|
Stack {
|
|
children: Vec::new(),
|
|
}
|
|
}
|
|
}
|
|
|
|
impl Element for Stack {
|
|
type LayoutState = ();
|
|
type PaintState = ();
|
|
|
|
fn layout(
|
|
&mut self,
|
|
constraint: SizeConstraint,
|
|
ctx: &mut LayoutContext,
|
|
) -> (Vector2F, Self::LayoutState) {
|
|
let mut size = constraint.min;
|
|
for child in &mut self.children {
|
|
size = size.max(child.layout(constraint, ctx));
|
|
}
|
|
(size, ())
|
|
}
|
|
|
|
fn after_layout(
|
|
&mut self,
|
|
_: Vector2F,
|
|
_: &mut Self::LayoutState,
|
|
ctx: &mut AfterLayoutContext,
|
|
) {
|
|
for child in &mut self.children {
|
|
child.after_layout(ctx);
|
|
}
|
|
}
|
|
|
|
fn paint(
|
|
&mut self,
|
|
bounds: pathfinder_geometry::rect::RectF,
|
|
_: &mut Self::LayoutState,
|
|
ctx: &mut PaintContext,
|
|
) -> Self::PaintState {
|
|
for child in &mut self.children {
|
|
child.paint(bounds.origin(), ctx);
|
|
}
|
|
}
|
|
|
|
fn dispatch_event(
|
|
&mut self,
|
|
event: &Event,
|
|
_: pathfinder_geometry::rect::RectF,
|
|
_: &mut Self::LayoutState,
|
|
_: &mut Self::PaintState,
|
|
ctx: &mut EventContext,
|
|
) -> bool {
|
|
for child in self.children.iter_mut().rev() {
|
|
if child.dispatch_event(event, ctx) {
|
|
return true;
|
|
}
|
|
}
|
|
false
|
|
}
|
|
}
|
|
|
|
impl Extend<ElementBox> for Stack {
|
|
fn extend<T: IntoIterator<Item = ElementBox>>(&mut self, children: T) {
|
|
self.children.extend(children)
|
|
}
|
|
}
|