ControlObservable<T> class

The primary concrete implementation of an observable value.

This class manages a value, a list of subscribers, and handles the logic for notifying subscribers when the value changes. It also provides factory constructors to easily create observables from other reactive sources like Streams and Futures.

Inheritance

Object
ObservableValue<T>
ObservableModel<T>
ControlObservable

Implementers

Available extensions

Constructors

ControlObservable(T _value): Observable that handles listeners and value changes. Initial value of this object. This object must call dispose to release resources.

Properties

hashCode → int: The hash code for this object.
no setterinherited
internalData ↔ dynamic: Optional data that can be attached to the observable, often for internal use by components or for tracking purposes.
getter/setter pairinherited
isActive → bool: Checks availability of this observable. Inactive observers should not be notified.
no setteroverride
isEmpty → bool: Checks if value is not set.
no setterinherited
isFalse → bool: Available on ObservableModel<bool>, provided by the ObservableBoolExt extension
Checks if the observable's current value is false or null.
no setter
isNotEmpty → bool: Checks if value is set.
no setterinherited
isTrue → bool: Available on ObservableModel<bool>, provided by the ObservableBoolExt extension
Checks if the observable's current value is true.
no setter
isValid → bool: Checks validity of this observable. Invalid observers should not be notified.
no setteroverride
runtimeType → Type: A representation of the runtime type of the object.
no setterinherited
subCount → int: Number of active listeners.
no setter
subs → List<ControlSubscription<T>>: Active subscriptions of this observable. This is exposed just for debug and test purposes. DO NOT modify this list externally!
final
value ↔ T: The current value held by the observable.
getter/setter pairinherited-setteroverride-getter

Methods

cancel(ControlSubscription<T> subscription) → void: Cancels a subscription, preventing it from receiving further notifications.
override
cast() → ObservableValue: Available on ObservableValue, provided by the ObservableValuExt extension
Cast this observable.
clear() → void: Invalidates and clears all subs.
createSubscription([dynamic args]) → ControlSubscription<T>
dispose() → void: Releases resources used by the object.
override
disposeWith(DisposeObserver observer) → void: Available on Disposable, provided by the DisposableExt extension
Register for dispose with given observer.
listen(VoidCallback action) → ControlSubscription<T>: Subscribes to the observable to be notified of changes.
inherited
merge(Object other) → ObservableGroup: Available on ObservableBase, provided by the ObservableBaseExt extension
Creates new group, that listens to both observables.
noSuchMethod(Invocation invocation) → dynamic: Invoked when a nonexistent method or property is accessed.
inherited
notify() → void: Notify this object to propagate changes.
override
pause() → void: When observable is paused, then notify breaks all callbacks.
resume() → bool: Resume notify to listeners. Only isValid observable can be resumed.
setFalse() → void: Available on ObservableModel<bool>, provided by the ObservableBoolExt extension
Sets the observable's value to false and notifies listeners.
setTrue() → void: Available on ObservableModel<bool>, provided by the ObservableBoolExt extension
Sets the observable's value to true and notifies listeners.
setValue(T value, {bool notify = true, bool forceNotify = false}) → void: Sets the observable's value.
override
subscribe(ValueCallback<T> action, {bool current = false, dynamic args}) → ControlSubscription<T>: Subscribes to changes in the observable's value.
override
toggle() → bool: Available on ObservableModel<bool>, provided by the ObservableBoolExt extension
Toggles the boolean value (true to false, or false/null to true) and notifies listeners.
toString() → String: A string representation of this object.
inherited
wrap(ObservableValue other, {T converter(U value)?, bool autoDispose = true}) → ControlSubscription

Operators

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

Static Methods

empty<T>([T? value]) → ControlObservable<T?>: Creates an observable that can hold a nullable value.
handle<T>(ObservableModel<T?> observable) → ObservableValue<T?>: Wraps an existing observable to hide its concrete implementation, exposing only the ObservableValue interface.
of<T>(Object? object) → ObservableValue<T?>: A powerful factory that creates an ObservableValue from various sources.
ofChannel<T>(ObservableBase channel) → ControlObservable<T?>: Creates an observable from given channel. This object wraps channel and propagates their notifies.
ofFuture<T>(Future<T> future) → ControlObservable<T?>: Creates an observable from given future. Future value is propagated to this observable. This object waits to future completion and then sets value. If error occurs nothing happens.
ofListenable<T>(Listenable listenable) → ControlObservable<T?>: Creates an observable from given listenable. Listenable value, if any, is propagated to this observable. This object listen to listenable and notifies about value changes (if ValueListenable is given).
ofStream<T>(Stream<T> stream) → ControlObservable<T?>: Creates an observable from given stream. Stream value is propagated to this observable. This object listen to stream and notifies about value changes.