Struct zng_app::widget::info::WidgetInfoTree

pub struct WidgetInfoTree(/* private fields */);

A tree of WidgetInfo.

The tree is behind an Arc pointer so cloning and storing this type is very cheap.

Instantiated using WidgetInfoBuilder.

Implementations

impl WidgetInfoTree

pub fn access_enabled(&self) -> AccessEnabled

If this tree contains accessibility information.

If accessibility is enabled for the window and will stay enabled for its lifetime.

pub fn to_access_tree(&self) -> AccessTree

Build an access tree from the info tree.

If not access_enabled returns a placeholder tree with only the root node.

pub fn to_access_updates(&self, prev_tree: &Self) -> Option<AccessTreeUpdate>

Build partial or full access trees for updated widgets.

Returns None if not access_enabled or no access info has changed. The focused value is always set to the root ID, it must be changed to the correct focused widget.

This is usually called by window implementers just after the next frame after info rebuild. Note that these updates will also include to_access_updates_bounds.

pub fn to_access_updates_bounds(&self) -> Option<AccessTreeUpdate>

Build partial access trees for widgets that changed transform, size or visibility.

Returns None if not access_enabled or no transform/visibility changed. The focused value is always set to the root ID, it must be changed to the correct focused widget.

This is usually called by window implementers after each frame that is not to_access_updates.

impl WidgetInfoTree

pub fn wgt(window_id: WindowId, root_id: WidgetId) -> Self

Blank window that contains only the root widget taking no space.

pub fn stats(&self) -> WidgetInfoTreeStats

Statistics abound the info tree.

pub fn scale_factor(&self) -> Factor

Scale factor of the last rendered frame.

pub fn view_process_gen(&self) -> ViewProcessGen

View-process generation.

Is ViewProcessGen::INVALID before first render and in headless apps.

pub fn build_meta(&self) -> StateMapRef<'_, WidgetInfoMeta>

Custom metadata associated with the tree during info build.

Any widget (that was not reused) can have inserted metadata.

pub fn root(&self) -> WidgetInfo

Reference to the root widget in the tree.

pub fn all_widgets(&self) -> TreeIter

All widgets including root.

pub fn window_id(&self) -> WindowId

Id of the window that owns all widgets represented in the tree.

pub fn get(&self, widget_id: impl Into<WidgetId>) -> Option<WidgetInfo>

Reference to the widget in the tree, if it is present.

pub fn contains(&self, widget_id: impl Into<WidgetId>) -> bool

If the tree contains the widget.

pub fn get_or_parent(&self, path: &WidgetPath) -> Option<WidgetInfo>

Reference to the widget or first parent that is present.

pub fn is_rendered(&self) -> bool

If the widgets in this tree have been rendered at least once, after the first render the widget bounds info are always up-to-date and spatial queries can be made on the widgets.

pub fn out_of_bounds(&self) -> impl ExactSizeIterator<Item = WidgetInfo>

Iterator over all widgets with inner-bounds not fully contained by their parent inner bounds.

pub fn spatial_bounds(&self) -> PxRect

Gets the bounds box that envelops all widgets, including the out-of-bounds widgets.

pub fn len(&self) -> usize

Total number of widgets in the tree.

Is never zero, every tree has at least the root widget.

Trait Implementations

impl Clone for WidgetInfoTree

fn clone(&self) -> WidgetInfoTree

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for WidgetInfoTree

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl PartialEq for WidgetInfoTree

fn eq(&self, other: &Self) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Eq for WidgetInfoTree