SemanticsOwner class

Owns SemanticsNode objects and notifies listeners of changes to the render tree semantics.

To listen for semantic updates, call SemanticsBinding.ensureSemantics or PipelineOwner.ensureSemantics to obtain a SemanticsHandle. This will create a SemanticsOwner if necessary.

Inheritance

Constructors

SemanticsOwner({required SemanticsUpdateCallback onSemanticsUpdate})
Creates a SemanticsOwner that manages zero or more SemanticsNode objects.

Properties

hashCode int
The hash code for this object.
no setterinherited
hasListeners bool
Whether any listeners are currently registered.
no setterinherited
onSemanticsUpdate SemanticsUpdateCallback
The onSemanticsUpdate callback is expected to dispatch SemanticsUpdates to the FlutterView that is associated with this PipelineOwner and/or SemanticsOwner.
final
rootSemanticsNode SemanticsNode?
The root node of the semantics tree, if any.
no setter
runtimeType Type
A representation of the runtime type of the object.
no setterinherited

Methods

addListener(VoidCallback listener) → void
Register a closure to be called when the object changes.
inherited
dispose() → void
Discards any resources used by the object. After this is called, the object is not in a usable state and should be discarded (calls to addListener will throw after the object is disposed).
override
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
notifyListeners() → void
Call all the registered listeners.
inherited
performAction(int id, SemanticsAction action, [Object? args]) → void
Asks the SemanticsNode with the given id to perform the given action.
performActionAt(Offset position, SemanticsAction action, [Object? args]) → void
Asks the SemanticsNode at the given position to perform the given action.
removeListener(VoidCallback listener) → void
Remove a previously registered closure from the list of closures that are notified when the object changes.
inherited
sendSemanticsUpdate() → void
Update the semantics using onSemanticsUpdate.
toString() String
A string representation of this object.
override

Operators

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