Module info 

Widget info tree and info builder.

Examples

The example declares a new info state for widgets and a property that sets the new state. The new state is then used in a widget.

mod custom {
    use zng::prelude_wgt::*;

    static_id! {
        static ref STATE_ID: StateId<bool>;
    }

    #[property(CONTEXT)]
    pub fn flag_state(child: impl IntoUiNode, state: impl IntoVar<bool>) -> UiNode {
        let state = state.into_var();
        match_node(child, move |_, op| match op {
            UiNodeOp::Init => {
                WIDGET.sub_var_info(&state);
            }
            UiNodeOp::Info { info } => {
                info.set_meta(*STATE_ID, state.get());
            }
            _ => {}
        })
    }

    pub trait StateExt {
        fn state(&self) -> Option<bool>;
    }
    impl StateExt for WidgetInfo {
        fn state(&self) -> Option<bool> {
            self.meta().get_clone(*STATE_ID)
        }
    }
}

Wgt! {
    custom::flag_state = true;
    widget::on_info_init = hn!(|_| {
        use custom::StateExt as _;
        let info = WIDGET.info();
        println!("state: {:?}", info.state());
    });
}

Modules

access

Accessibility metadata types.

inspector

Helper types for inspecting an UI tree.

iter

Widget info tree iterators.

Structs

HitInfo

A hit-test hit.

HitTestInfo

A hit-test result.

InlineSegmentInfo

Info about a segment in the first or last row of an inlined widget.

InteractionPath

Represents a WidgetPath annotated with each widget’s Interactivity.

Interactivity

Represents the level of interaction allowed for a widget.

InteractivityFilterArgs

Argument for a interactivity filter function.

ParallelBuilder

Represents a builder split from the main builder that can be used in parallel and then folded back onto the main builder.

WidgetBorderInfo

Shared reference to the combined border and corner radius of a WidgetInfo.

WidgetBoundsInfo

Shared reference to layout size, offsets, rendered transforms and bounds of a widget.

WidgetDescendantsRange

Represents the descendants of a widget, allows checking if widgets are descendant with O(1) time.

WidgetInfo

Reference to a widget info in a WidgetInfoTree.

WidgetInfoBuilder

Widget info tree builder.

WidgetInfoTree

A tree of WidgetInfo.

WidgetInfoTreeStats

Stats over the lifetime of a widget info tree.

WidgetInlineInfo

Info about the inlined rows of the widget.

WidgetInlineMeasure

Info about the input inline connecting rows of the widget.

WidgetPath

Full address of a widget.

WidgetTreeChangedArgs

WIDGET_TREE_CHANGED_EVENT args.

Enums

RelativeHitZ

Hit-test result on a widget relative to it’s descendants.

TreeFilter

Widget tree filter selected for a widget in the tree.

WidgetInfoMeta

Tag for the WidgetInfo::meta state-map.

Statics

WIDGET_TREE_CHANGED_EVENT

A window widget tree was rebuild.