Struct zng::widget::builder::WidgetBuilding

pub struct WidgetBuilding { /* private fields */ }

Represents a finalizing WidgetBuilder.

Widgets can register a build action to get access to this, it provides an opportunity to remove or capture the final properties of a widget, after they have all been resolved and when assigns generated. Build actions can also define the child node, intrinsic nodes and a custom builder.

Implementations

impl WidgetBuilding

pub fn widget_type(&self) -> WidgetType

The widget that started this builder.

pub fn has_child(&self) -> bool

If an innermost node is defined.

If false by the end of build the FillUiNode is used as the innermost node.

pub fn set_child(&mut self, node: impl UiNode)

Set/replace the innermost node of the widget.

pub fn disable_inspector(&mut self)

Don’t insert the inspector node and inspector metadata on build.

The inspector metadata is inserted by default when feature="inspector" is active.

pub fn disable_trace_widget(&mut self)

Don’t insert the widget trace node on build.

The trace node is inserted by default when feature="trace_widget" is active.

pub fn disable_trace_wgt_item(&mut self)

Don’t insert property/intrinsic trace nodes on build.

The trace nodes is inserted by default when feature="trace_wgt_item" is active.

pub fn push_intrinsic<I>( &mut self, group: NestGroup, name: &'static str, intrinsic: impl FnOnce(Box<dyn UiNodeBoxed>) -> I + Send + Sync + 'static, )

where I: UiNode,

Insert intrinsic node, that is a core functionality node of the widget that cannot be overridden.

The name is used for inspector/trace only, intrinsic nodes are not deduplicated.

pub fn push_intrinsic_positioned<I>( &mut self, position: NestPosition, name: &'static str, intrinsic: impl FnOnce(Box<dyn UiNodeBoxed>) -> I + Send + Sync + 'static, )

where I: UiNode,

Insert intrinsic node with custom nest position.

The name is used for inspector/trace only, intrinsic nodes are not deduplicated.

pub fn remove_property( &mut self, property_id: PropertyId, ) -> Option<BuilderProperty>

Removes the property.

Note that if the property can already be captured by another widget component.

pub fn capture_property( &mut self, property_id: PropertyId, ) -> Option<BuilderPropertyRef<'_>>

Flags the property as captured and returns a reference to it.

Note that captured properties are not instantiated in the final build, but they also are not removed like unset. A property can be “captured” more then once, and if the "inspector" feature is enabled they can be inspected.

pub fn capture_var<T>( &mut self, property_id: PropertyId, ) -> Option<Box<dyn VarBoxed<T>>>

where T: VarValue,

Flags the property as captured and downcast the input var.

pub fn capture_var_or_else<T, F>( &mut self, property_id: PropertyId, or_else: impl FnOnce() -> F, ) -> Box<dyn VarBoxed<T>>

where T: VarValue, F: IntoVar<T>,

Flags the property as captured and downcast the input var, or calls or_else to generate a fallback.

pub fn capture_var_or_default<T>( &mut self, property_id: PropertyId, ) -> Box<dyn VarBoxed<T>>

where T: VarValue + Default,

Flags the property as captured and downcast the input var, returns a new one with the default value.

pub fn capture_ui_node( &mut self, property_id: PropertyId, ) -> Option<Box<dyn UiNodeBoxed>>

Flags the property as captured and get the input node.

pub fn capture_ui_node_or_else<F>( &mut self, property_id: PropertyId, or_else: impl FnOnce() -> F, ) -> Box<dyn UiNodeBoxed>

where F: UiNode,

Flags the property as captured and get the input node, or calls or_else to generate a fallback node.

pub fn capture_ui_node_list( &mut self, property_id: PropertyId, ) -> Option<Box<dyn UiNodeListBoxed>>

Flags the property as captured and get the input list.

pub fn capture_ui_node_list_or_else<F>( &mut self, property_id: PropertyId, or_else: impl FnOnce() -> F, ) -> Box<dyn UiNodeListBoxed>

where F: UiNodeList,

Flags the property as captured and get the input list, or calls or_else to generate a fallback list.

pub fn capture_ui_node_list_or_empty( &mut self, property_id: PropertyId, ) -> Box<dyn UiNodeListBoxed>

Flags the property as captured and get the input list, or returns an empty list.

pub fn capture_widget_handler<A>( &mut self, property_id: PropertyId, ) -> Option<ArcWidgetHandler<A>>

where A: Clone + 'static,

Flags the property as captured and downcast the input handler.

Methods from Deref<Target = WidgetBuilderProperties>

pub fn property( &self, property_id: PropertyId, ) -> Option<BuilderPropertyRef<'_>>

Reference the property, if it is present.

pub fn property_mut( &mut self, property_id: PropertyId, ) -> Option<BuilderPropertyMut<'_>>

Modify the property, if it is present.

pub fn properties(&self) -> impl Iterator<Item = BuilderPropertyRef<'_>>

Iterate over the current properties.

The properties may not be sorted in the correct order if the builder has never built.

pub fn properties_mut(&mut self) -> impl Iterator<Item = BuilderPropertyMut<'_>>

iterate over mutable references to the current properties.

pub fn capture_value<T>(&mut self, property_id: PropertyId) -> Option<T>

where T: VarValue,

Flags the property as captured and downcast the input value.

Unlike other property kinds you can capture values in the WidgetBuilder, note that the value may not the final value, unless you are capturing on build.

Other property kinds can only be captured in WidgetBuilding as their values strongly depend on the final when blocks that are only applied after building starts.

pub fn capture_value_or_else<T>( &mut self, property_id: PropertyId, or_else: impl FnOnce() -> T, ) -> T

where T: VarValue,

Flags the property as captured and downcast the input value, or calls or_else to generate the value.

pub fn capture_value_or_default<T>(&mut self, property_id: PropertyId) -> T

where T: VarValue + Default,

Flags the property as captured and downcast the input value, or returns the default value.

Trait Implementations

impl Deref for WidgetBuilding

type Target = WidgetBuilderProperties

The resulting type after dereferencing.

fn deref(&self) -> &<WidgetBuilding as Deref>::Target

Dereferences the value.

impl DerefMut for WidgetBuilding

fn deref_mut(&mut self) -> &mut <WidgetBuilding as Deref>::Target

Mutably dereferences the value.