VisibilityDetectorLayer class - VisibilityDetector library

Constructors

VisibilityDetectorLayer({required Key key, required Offset widgetOffset, required Size widgetSize, required Offset paintOffset, required VisibilityChangedCallback onVisibilityChanged}): Constructor. See the corresponding properties for parameter details.

Properties

alwaysNeedsAddToScene → bool: Subclasses may override this to true to disable retained rendering.
no setterinherited
attached → bool: Whether the layer tree containing this layer is attached to an owner.
no setterinherited
debugCreator ↔ Object?: The object responsible for creating this layer.
getter/setter pairinherited
debugDisposed → bool: If asserts are enabled, returns whether dispose has been called since the last time any retained resources were created.
no setterinherited
debugHandleCount → int: Returns the number of objects holding a LayerHandle to this layer.
no setterinherited
debugSubtreeNeedsAddToScene → bool?: Whether this or any descendant layer in the subtree needs addToScene.
no setterinherited
depth → int: The depth of this layer in the layer tree.
no setterinherited
engineLayer ↔ EngineLayer?: Stores the engine layer created for this layer in order to reuse engine resources across frames for better app performance.
getter/setter pairinherited
firstChild → Layer?: The first composited layer in this layer's child list.
no setterinherited
hasChildren → bool: Returns whether this layer has at least one child layer.
no setterinherited
hashCode → int: The hash code for this object.
no setterinherited
key → Key: The key for the corresponding VisibilityDetector widget.
final
lastChild → Layer?: The last composited layer in this layer's child list.
no setterinherited
nextSibling → Layer?: This layer's next sibling in the parent layer's child list.
no setterinherited
onVisibilityChanged → VisibilityChangedCallback: See VisibilityDetector.onVisibilityChanged.
final
owner → Object?: The owner for this layer (null if unattached).
no setterinherited
paintOffset → Offset: The offset supplied to RenderVisibilityDetector.paint method.
final
parent → ContainerLayer?: This layer's parent in the layer tree.
no setterinherited
previousSibling → Layer?: This layer's previous sibling in the parent layer's child list.
no setterinherited
runtimeType → Type: A representation of the runtime type of the object.
no setterinherited
subtreeHasCompositionCallbacks → bool: Whether the subtree rooted at this layer has any composition callback observers.
no setterinherited
widgetOffset → Offset: Offset to the start of the widget, in local coordinates.
final
widgetSize → Size: The size of the corresponding VisibilityDetector widget.
final

Methods

addChildrenToScene(SceneBuilder builder) → void: Uploads all of this layer's children to the engine.
inherited
addCompositionCallback(CompositionCallback callback) → VoidCallback: Adds a callback for when the layer tree that this layer is part of gets composited, or when it is detached and will not be rendered again.
inherited
addToScene(SceneBuilder builder, [Offset layerOffset = Offset.zero]) → void: See Layer.addToScene.
override
append(Layer child) → void: Adds the given layer to the end of this layer's child list.
inherited
applyTransform(Layer? child, Matrix4 transform) → void: Applies the transform that would be applied when compositing the given child to the given matrix.
inherited
attach(covariant Object owner) → void: See AbstractNode.attach.
override
buildScene(SceneBuilder builder) → Scene: Consider this layer as the root and build a scene (a tree of layers) in the engine.
inherited
debugDescribeChildren() → List<DiagnosticsNode>: Returns a list of DiagnosticsNode objects describing this node's children.
inherited
debugFillProperties(DiagnosticPropertiesBuilder properties) → void: See Diagnosticable.debugFillProperties.
override
debugMarkClean() → void: Mark that this layer is in sync with engine.
inherited
depthFirstIterateChildren() → List<Layer>: Returns the descendants of this layer in depth first order.
inherited
describeClipBounds() → Rect?: Describes the clip that would be applied to contents of this layer, if any.
inherited
detach() → void: See AbstractNode.detach.
override
dispose() → void: Clears any retained resources that this layer holds.
inherited
find<S extends Object>(Offset localPosition) → S?: Search this layer and its subtree for the first annotation of type S under the point described by localPosition.
inherited
findAllAnnotations<S extends Object>(Offset localPosition) → AnnotationResult<S>: Search this layer and its subtree for all annotations of type S under the point described by localPosition.
inherited
findAnnotations<S extends Object>(AnnotationResult<S> result, Offset localPosition, {required bool onlyFirst}) → bool: Search this layer and its subtree for annotations of type S at the location described by localPosition.
inherited
markNeedsAddToScene() → void: Mark that this layer has changed and addToScene needs to be called.
inherited
noSuchMethod(Invocation invocation) → dynamic: Invoked when a nonexistent method or property is accessed.
inherited
redepthChild(Layer child) → void: Adjust the depth of the given child to be greater than this node's own depth.
inherited
redepthChildren() → void: Adjust the depth of this node's children, if any.
inherited
remove() → void: Removes this layer from its parent layer's child list.
inherited
removeAllChildren() → void: Removes all of this layer's children from its child list.
inherited
supportsRasterization() → bool: Whether or not this layer, or any child layers, can be rasterized with ui.Scene.toImage or ui.Scene.toImageSync.
inherited
toDiagnosticsNode({String? name, DiagnosticsTreeStyle? style}) → DiagnosticsNode: Returns a debug representation of the object that is used by debugging tools and by DiagnosticsNode.toStringDeep.
inherited
toString({DiagnosticLevel minLevel = DiagnosticLevel.info}) → String: A string representation of this object.
inherited
toStringDeep({String prefixLineOne = '', String? prefixOtherLines, DiagnosticLevel minLevel = DiagnosticLevel.debug, int wrapWidth = 65}) → String: Returns a string representation of this node and its descendants.
inherited
toStringShallow({String joiner = ', ', DiagnosticLevel minLevel = DiagnosticLevel.debug}) → String: Returns a one-line detailed description of the object.
inherited
toStringShort() → String: A brief description of this object, usually just the runtimeType and the hashCode.
inherited
updateSubtreeNeedsAddToScene() → void: Traverses the layer subtree starting from this layer and determines whether it needs addToScene.
inherited

Operators

operator ==(Object other) → bool: The equality operator.
inherited

Static Properties

widgetBounds → Map<Key, Rect>: Keeps track of the last known bounds of a VisibilityDetector, in global coordinates.
no setter

Static Methods

forget(Key key) → void: Removes entries corresponding to the specified Key from our internal caches.
notifyNow() → void: See VisibilityDetectorController.notifyNow.