Struct WidgetTree 

pub struct WidgetTree { /* private fields */ }

The widget tree: a thin, typed wrapper over tree_arena::TreeArena.

Implementations

impl WidgetTree

pub fn new() -> Self

Create an empty tree.

pub fn insert_root(&mut self, pod: WidgetPod) -> WidgetId

Insert pod as a root of the tree, returning its id.

pub fn insert_child( &mut self, parent: WidgetId, pod: WidgetPod, ) -> Option<WidgetId>

Insert pod as a child of parent; None if parent is not in the tree.

pub fn pod(&self, id: WidgetId) -> Option<&WidgetPod>

Shared access to the pod with the given id, anywhere in the tree.

pub fn pod_mut(&mut self, id: WidgetId) -> Option<&mut WidgetPod>

Mutable access to the pod with the given id, anywhere in the tree.

pub fn roots(&self) -> Vec<WidgetId>

The tree’s root ids, in insertion order.

pub fn children(&self, id: WidgetId) -> Vec<WidgetId>

The children of id in insertion order; empty if id is absent or childless.

pub fn inspect(&self) -> Vec<InspectNode>

A read-only pre-order snapshot of the whole retained tree (siblings in declaration order).

Covers both child mechanisms: arena children, then the ChildPods a widget publishes through Widget::visit_children (a container that does not override it reads as a leaf). Bounds come from the last layout pass, so call it after one or the rects are zero-sized.

pub fn inspect_layout_dirty(&self) -> Vec<(WidgetId, bool)>

Per-node layout-dirty state for tooling and tests: one (id, layout_dirty) pair per node WidgetTree::inspect reports, in its order, so the two zip.

A ChildPod reports ChildPod::is_layout_dirty; an arena WidgetPod always reports false (the root lays it out unconditionally). Kept beside inspect so the plain InspectNode shape does not change.

pub fn inspect_paint_dirty(&self) -> Vec<(WidgetId, bool)>

Per-node paint-dirty state: the twin of WidgetTree::inspect_layout_dirty reporting ChildPod::is_paint_dirty; an arena WidgetPod reports false.

Trait Implementations

impl Default for WidgetTree

fn default() -> Self

Returns the “default value” for a type.