ValueSubject<T> class

A subject that provides synchronous access to the most recently added item. Additionally, if a value has been added subscribers are notified immediately of that value on subscription (as well as the events that are added in the future).

ValueSubject always behaves as a broadcast stream, and as such supports multiple subscribers.

Note that ValueSubject is conceptually identical to BehaviorSubject from other Rx.net oriented libraries.

Inheritance
Implemented types
Available extensions

Constructors

ValueSubject.new({bool sync = false})
Contructs a new ValueSubject.
factory
ValueSubject.initialValue(T initialValue, {bool sync = false})
Constructs a new ValueSubject seeded with an initial value.
factory
ValueSubject.lazy(T initialValue(), {bool sync = false})
Constructs a new ValueSubject with an initial value that is not generated until value is read.
factory

Properties

error AsyncError
The last emitted error,
no setteroverride
first Future<T>
The first element of this stream.
no setterinherited
hasError bool
True if an error has been emitted.
no setteroverride
hashCode int
The hash code for this object.
no setterinherited
hasValue bool
True if at least one event has been emitted.
no setteroverride
isBroadcast bool
Whether this stream is a broadcast stream.
no setteroverride
isConstructed bool

Available on ValueStream<LifecycleState>, provided by the LifecycleStreamExtensions extension

Indicates if the current value is LifecycleState.constructed.
no setter
isDisposed bool

Available on ValueStream<LifecycleState>, provided by the LifecycleStreamExtensions extension

Indicates if the current value is LifecycleState.disposed.
no setter
isEmpty Future<bool>
Whether this stream contains any elements.
no setterinherited
isStarted bool

Available on ValueStream<LifecycleState>, provided by the LifecycleStreamExtensions extension

Indicates if the current value is LifecycleState.started.
no setter
isStarting bool

Available on ValueStream<LifecycleState>, provided by the LifecycleStreamExtensions extension

Indicates if the current value is LifecycleState.starting.
no setter
isStopped bool

Available on ValueStream<LifecycleState>, provided by the LifecycleStreamExtensions extension

Indicates if the current value is LifecycleState.stopped.
no setter
isStopping bool

Available on ValueStream<LifecycleState>, provided by the LifecycleStreamExtensions extension

Indicates if the current value is LifecycleState.stopping.
no setter
last Future<T>
The last element of this stream.
no setterinherited
length Future<int>
The number of elements in this stream.
no setterinherited
runtimeType Type
A representation of the runtime type of the object.
no setterinherited
single Future<T>
The single element of this stream.
no setterinherited
value → T
The last emitted value.
no setteroverride

Methods

add(T event) → void
Adds a data event to the sink.
override
addError(Object error, [StackTrace? stackTrace]) → void
Adds an error to the sink.
override
addStream(Stream<T> stream, {bool? cancelOnError}) Future<void>
Consumes the elements of stream.
override
any(bool test(T element)) Future<bool>
Checks whether test accepts any element provided by this stream.
inherited
asBroadcastStream({void onListen(StreamSubscription<T> subscription)?, void onCancel(StreamSubscription<T> subscription)?}) Stream<T>
Returns a multi-subscription stream that produces the same events as this.
inherited
asyncExpand<E>(Stream<E>? convert(T event)) Stream<E>
Transforms each element into a sequence of asynchronous events.
inherited
asyncMap<E>(FutureOr<E> convert(T event)) Stream<E>
Creates a new stream with each data event of this stream asynchronously mapped to a new event.
inherited
cast<R>() Stream<R>
Adapt this stream to be a Stream<R>.
inherited
close() Future<void>
Closes the sink.
override
contains(Object? needle) Future<bool>
Returns whether needle occurs in the elements provided by this stream.
inherited
distinct([bool equals(T previous, T next)?]) Stream<T>
Skips data events if they are equal to the previous data event.
inherited
drain<E>([E? futureValue]) Future<E>
Discards all data on this stream, but signals when it is done or an error occurred.
inherited
elementAt(int index) Future<T>
Returns the value of the indexth data event of this stream.
inherited
every(bool test(T element)) Future<bool>
Checks whether test accepts all elements provided by this stream.
inherited
expand<S>(Iterable<S> convert(T element)) Stream<S>
Transforms each element of this stream into a sequence of elements.
inherited
firstWhere(bool test(T element), {T orElse()?}) Future<T>
Finds the first element of this stream matching test.
inherited
fold<S>(S initialValue, S combine(S previous, T element)) Future<S>
Combines a sequence of values by repeatedly applying combine.
inherited
forEach(void action(T element)) Future<void>
Executes action on each element of this stream.
inherited
handleError(Function onError, {bool test(dynamic error)?}) Stream<T>
Creates a wrapper Stream that intercepts some errors from this stream.
inherited
join([String separator = ""]) Future<String>
Combines the string representation of elements into a single string.
inherited
lastWhere(bool test(T element), {T orElse()?}) Future<T>
Finds the last element in this stream matching test.
inherited
listen(void onData(T value)?, {Function? onError, void onDone()?, bool? cancelOnError}) StreamSubscription<T>
Adds a subscription to this stream.
override
map<S>(S convert(T event)) Stream<S>
Transforms each element of this stream into a new stream event.
inherited
mapValueStream<R>(R convert(T value), {bool sync = false}) ValueStream<R>
Returns a ValueStream that converts each element of this stream to a new value using the convert function, and emits the result.
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
pipe(StreamConsumer<T> streamConsumer) Future
Pipes the events of this stream into streamConsumer.
inherited
reduce(T combine(T previous, T element)) Future<T>
Combines a sequence of values by repeatedly applying combine.
inherited
singleWhere(bool test(T element), {T orElse()?}) Future<T>
Finds the single element in this stream matching test.
inherited
skip(int count) Stream<T>
Skips the first count data events from this stream.
inherited
skipWhile(bool test(T element)) Stream<T>
Skip data events from this stream while they are matched by test.
inherited
take(int count) Stream<T>
Provides at most the first count data events of this stream.
inherited
takeWhile(bool test(T element)) Stream<T>
Forwards data events while test is successful.
inherited
timeout(Duration timeLimit, {void onTimeout(EventSink<T> sink)?}) Stream<T>
Creates a new stream with the same events as this stream.
inherited
toList() Future<List<T>>
Collects all elements of this stream in a List.
inherited
toSet() Future<Set<T>>
Collects the data of this stream in a Set.
inherited
toString() String
A string representation of this object.
inherited
transform<S>(StreamTransformer<T, S> streamTransformer) Stream<S>
Applies streamTransformer to this stream.
inherited
where(bool test(T event)) Stream<T>
Creates a new stream from this stream that discards some elements.
inherited

Operators

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