dan/despot
1
0
Fork 0
mirror of https://github.com/danbulant/despot synced 2026-07-05 11:00:53 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

add docs

Browse source
This commit is contained in:
Daniel Bulant 2024-10-25 22:27:07 +02:00
parent d5ec39ea53
commit 780bfabaa5
No known key found for this signature in database
1 changed files with 14 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

14
src/widgets/virtual_list.rs
View file

@ -8,9 +8,14 @@ use super::owned::OwnedWidget;
/// This simple virtual list assumes that all items have the same height, width and that the item count is known. /// This simple virtual list assumes that all items have the same height, width and that the item count is known.
/// All the values are dynamic, so the list will update when the values change. /// All the values are dynamic, so the list will update when the values change.
pub trait VirtualListContent: Debug { pub trait VirtualListContent: Debug {
/// Single item height
fn item_height(&self) -> impl IntoValue<Dimension>; fn item_height(&self) -> impl IntoValue<Dimension>;
/// Width of the items
fn width(&self) -> impl IntoValue<Dimension>; fn width(&self) -> impl IntoValue<Dimension>;
/// Number of items
fn item_count(&self) -> impl IntoValue<usize>; fn item_count(&self) -> impl IntoValue<usize>;
/// Create a widget for the item at the given index.
/// This is called when the widget comes into view. The widget may be removed at any moment (by scrolling it out of view) and recreated later.
fn widget_at(&self, index: usize) -> impl MakeWidget; fn widget_at(&self, index: usize) -> impl MakeWidget;
} }
@ -21,17 +26,25 @@ struct VirtualListItem {
} }
#[derive(Debug)] #[derive(Debug)]
/// A virtual list widget.
/// Requires a [VirtualListContent] trait implementation to render the items.
/// Items are lazily recreated as they go in and out of view.
pub struct VirtualList<T: VirtualListContent + Send + 'static> { pub struct VirtualList<T: VirtualListContent + Send + 'static> {
virtual_list: T, virtual_list: T,
vertical_scroll: OwnedWidget<ScrollBar>, vertical_scroll: OwnedWidget<ScrollBar>,
items: VecDeque<VirtualListItem>, items: VecDeque<VirtualListItem>,
content_size: Dynamic<Size<UPx>>, content_size: Dynamic<Size<UPx>>,
/// Maximum scroll value - max_scroll.y + control_size.height should be the height of the content.
pub max_scroll: DynamicReader<Point<UPx>>, pub max_scroll: DynamicReader<Point<UPx>>,
/// Current scroll value. The x value is always 0. Change the value to scroll the widget programmatically.
pub scroll: Dynamic<Point<UPx>>, pub scroll: Dynamic<Point<UPx>>,
control_size: Dynamic<Size<UPx>>, control_size: Dynamic<Size<UPx>>,
/// Height of an item. Based on [VirtualListContent::item_height].
pub item_height: DynamicReader<Dimension>, pub item_height: DynamicReader<Dimension>,
/// Width of the items. Based on [VirtualListContent::width].
pub width: DynamicReader<Dimension>, pub width: DynamicReader<Dimension>,
/// Number of items. Based on [VirtualListContent::item_count].
pub item_count: DynamicReader<usize>, pub item_count: DynamicReader<usize>,
visible_range: Dynamic<Range<usize>> visible_range: Dynamic<Range<usize>>
@ -99,6 +112,7 @@ impl<T: VirtualListContent + Send + 'static> VirtualList<T> {
self.control_size.create_reader() self.control_size.create_reader()
} }
/// Returns a reader for number of visible items. 0 indexed.
#[must_use] #[must_use]
pub fn visible_range(&self) -> DynamicReader<Range<usize>> { pub fn visible_range(&self) -> DynamicReader<Range<usize>> {
self.visible_range.create_reader() self.visible_range.create_reader()