ValueNotifier<T> class Null safety

A ChangeNotifier that holds a single value.

When value is replaced with something that is not equal to the old value as evaluated by the equality operator ==, this class notifies its listeners.

Inheritance
Implemented types
Implementers

Constructors

ValueNotifier(T _value)
Creates a ChangeNotifier that wraps this value.

Properties

hashCode int
The hash code for this object.
read-onlyinherited
hasListeners bool
Whether any listeners are currently registered.
protected">@protectedread-onlyinherited
runtimeType Type
A representation of the runtime type of the object.
read-onlyinherited
value ↔ T
The current value stored in this notifier.
read / writeoverride-getter

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).
mustCallSuper">@mustCallSuperinherited
noSuchMethod(Invocation invocation) → dynamic
Invoked when a non-existent method or property is accessed.
inherited
notifyListeners() → void
Call all the registered listeners.
protected">@protectedvisibleForTesting">@visibleForTestinginherited
removeListener(VoidCallback listener) → void
Remove a previously registered closure from the list of closures that are notified when the object changes.
inherited
toString() String
A string representation of this object.
override

Operators

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