In UniformList, guard against misbehavior of append_items

If for some reason the handle got dropped and we call it, we'll deal with it somewhat gracefully.

Co-Authored-By: Max Brunsfeld <maxbrunsfeld@gmail.com>
This commit is contained in:
Nathan Sobo 2022-05-26 18:30:28 -06:00
parent 8dd82fdce1
commit b6b16fc9c3

View File

@ -44,7 +44,7 @@ pub struct LayoutState {
pub struct UniformList {
state: UniformListState,
item_count: usize,
append_items: Box<dyn Fn(Range<usize>, &mut Vec<ElementBox>, &mut LayoutContext) -> bool>,
append_items: Box<dyn Fn(Range<usize>, &mut Vec<ElementBox>, &mut LayoutContext)>,
padding_top: f32,
padding_bottom: f32,
get_width_from_item: Option<usize>,
@ -70,9 +70,6 @@ impl UniformList {
cx.render(&handle, |view, cx| {
append_items(view, range, items, cx);
});
true
} else {
false
}
}),
padding_top: 0.,
@ -172,40 +169,51 @@ impl Element for UniformList {
);
}
let no_items = (
constraint.min,
LayoutState {
item_height: 0.,
scroll_max: 0.,
items: Default::default(),
},
);
if self.item_count == 0 {
return (
constraint.min,
LayoutState {
item_height: 0.,
scroll_max: 0.,
items: Default::default(),
},
);
return no_items;
}
let mut items = Vec::new();
let mut size = constraint.max;
let mut item_size;
let sample_item_ix;
let mut sample_item;
let sample_item;
if let Some(sample_ix) = self.get_width_from_item {
(self.append_items)(sample_ix..sample_ix + 1, &mut items, cx);
sample_item_ix = sample_ix;
sample_item = items.pop().unwrap();
item_size = sample_item.layout(constraint, cx);
size.set_x(item_size.x());
if let Some(mut item) = items.pop() {
item_size = item.layout(constraint, cx);
size.set_x(item_size.x());
sample_item = item;
} else {
return no_items;
}
} else {
(self.append_items)(0..1, &mut items, cx);
sample_item_ix = 0;
sample_item = items.pop().unwrap();
item_size = sample_item.layout(
SizeConstraint::new(
vec2f(constraint.max.x(), 0.0),
vec2f(constraint.max.x(), f32::INFINITY),
),
cx,
);
item_size.set_x(size.x());
if let Some(mut item) = items.pop() {
item_size = item.layout(
SizeConstraint::new(
vec2f(constraint.max.x(), 0.0),
vec2f(constraint.max.x(), f32::INFINITY),
),
cx,
);
item_size.set_x(size.x());
sample_item = item
} else {
return no_items;
}
}
let item_constraint = SizeConstraint {