MaterialStatesController class Null safety

Manages a set of MaterialStates and notifies listeners of changes.

Used by widgets that expose their internal state for the sake of extensions that add support for additional states. See TextButton.statesController for example.

The controller's value is its current set of states. Listeners are notified whenever the value changes. The value should only be changed with update; it should not be modified directly.



MaterialStatesController([Set<MaterialState>? value])
Creates a MaterialStatesController.


hashCode int
The hash code for this object.
read-only, inherited
hasListeners bool
Whether any listeners are currently registered.
@protected, read-only, inherited
runtimeType Type
A representation of the runtime type of the object.
read-only, inherited
value Set<MaterialState>
The current value stored in this notifier.
read / write, inherited


addListener(VoidCallback listener) → void
Register a closure to be called when the object changes.
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).
@mustCallSuper, inherited
noSuchMethod(Invocation invocation) → dynamic
Invoked when a non-existent method or property is accessed.
notifyListeners() → void
Call all the registered listeners.
removeListener(VoidCallback listener) → void
Remove a previously registered closure from the list of closures that are notified when the object changes.
toString() String
A string representation of this object.
update(MaterialState state, bool add) → void
Adds state to value if add is true, and removes it otherwise, and notifies listeners if value has changed.


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