ValueStream<T> class
abstract
An Stream that provides synchronous access to the last emitted item
- Implemented types
-
- Stream<
T>
- Stream<
- Available extensions
Constructors
Properties
- error → Object
-
Returns last emitted error, failing if there is no error.
no setter
- errorOrNull → Object?
-
Last emitted error, or
nullif no error added.no setter -
first
→ Future<
T> -
The first element of this stream.
no setterinherited
- hasError → bool
-
Returns
truewhen error is available.no setter - hashCode → int
-
The hash code for this object.
no setterinherited
- hasValue → bool
-
Returns
truewhen value is available.no setter - isBroadcast → bool
-
Whether this stream is a broadcast stream.
no setterinherited
-
isEmpty
→ Future<
bool> -
Whether this stream contains any elements.
no setterinherited
-
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
- stackTrace → StackTrace?
-
Returns StackTrace of the last emitted error,
or
nullif no error added or the added error has no StackTrace.no setter - value → T
-
Returns the last emitted value, failing if there is no value.
See hasValue to determine whether value has already been set.
no setter
- valueOrNull → T?
-
Returns either value, or
null, should value not yet have been set.no setter
Methods
-
any(
bool test(T element)) → Future< bool> -
Checks whether
testaccepts 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 -
contains(
Object? needle) → Future< bool> -
Returns whether
needleoccurs in the elements provided by this stream.inherited -
debounce(
Stream window(T event)) → Stream< T> -
Available on Stream<
Transforms a Stream so that will only emit items from the source sequence if aT> , provided by the DebounceExtensions extensionwindowhas completed, without the source sequence emitting another item. -
debounceTime(
Duration duration) → Stream< T> -
Available on Stream<
Transforms a Stream so that will only emit items from the source sequence whenever the time span defined byT> , provided by the DebounceExtensions extensiondurationpasses, without the source sequence emitting another item. -
distinct(
[bool equals(T previous, T next)?]) → Stream< T> -
Skips data events if they are equal to the previous data event.
inherited
-
distinctBy<
S> ([S field(T event)?]) → Stream< T> -
Available on Stream<
use for FlowR.stream or flowr/FrViewModel.streamT> , provided by the DistinctByX extension -
distinctBy<
S> ([S field(T event)?]) → ValueStream< T> -
Available on ValueStream<
distinctBy for ValueStreamT> , provided by the DistinctByValueX extension -
distinctWith<
S> (S field(T event)) → Stream< S> -
Available on Stream<
use for FlowR.stream or flowr.FrViewModel.streamT> , provided by the DistinctWithX extension -
distinctWith<
S> (S field(T event)) → ValueStream< S> -
Available on ValueStream<
distinctBy for ValueStreamT> , provided by the DistinctWithValueX extension -
doOnCancel(
FutureOr< void> onCancel()) → Stream<T> -
Available on Stream<
Invokes the given callback function when the stream subscription is cancelled. Often called doOnUnsubscribe or doOnDispose in other implementations.T> , provided by the DoExtensions extension -
doOnData(
void onData(T event)) → Stream< T> -
Available on Stream<
Invokes the given callback function when the stream emits an item. In other implementations, this is called doOnNext.T> , provided by the DoExtensions extension -
doOnDone(
void onDone()) → Stream< T> -
Available on Stream<
Invokes the given callback function when the stream finishes emitting items. In other implementations, this is called doOnComplete(d).T> , provided by the DoExtensions extension -
doOnEach(
void onEach(Notification< T> notification)) → Stream<T> -
Available on Stream<
Invokes the given callback function when the stream emits data, emits an error, or emits done. The callback receives aT> , provided by the DoExtensions extensionNotificationobject. -
doOnError(
void onError(Object, StackTrace)) → Stream< T> -
Available on Stream<
Invokes the given callback function when the stream emits an error.T> , provided by the DoExtensions extension -
doOnListen(
void onListen()) → Stream< T> -
Available on Stream<
Invokes the given callback function when the stream is first listened to.T> , provided by the DoExtensions extension -
doOnPause(
void onPause()) → Stream< T> -
Available on Stream<
Invokes the given callback function when the stream subscription is paused.T> , provided by the DoExtensions extension -
doOnResume(
void onResume()) → Stream< T> -
Available on Stream<
Invokes the given callback function when the stream subscription resumes receiving items.T> , provided by the DoExtensions extension -
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
testaccepts 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
actionon 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 event)?, {Function? onError, void onDone()?, bool? cancelOnError}) → StreamSubscription< T> -
Adds a subscription to this stream.
inherited
-
map<
S> (S convert(T event)) → Stream< S> -
Transforms each element of this stream into a new stream event.
inherited
-
mapValue<
U> (U mapper(T value)) → ValueStream< U> -
Available on ValueStream<
map for ValueStreamT> , provided by the MapValueX extension -
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 -
publish(
) → PublishConnectableStream< T> -
Available on Stream<
Convert the current Stream into aT> , provided by the ConnectableStreamExtensions extensionConnectableStreamthat can be listened to multiple times. It will not begin emitting items from the original Stream until theconnectmethod is invoked. -
publishReplay(
{int? maxSize}) → ReplayConnectableStream< T> -
Available on Stream<
Convert the current Stream into aT> , provided by the ConnectableStreamExtensions extensionReplayConnectableStreamthat can be listened to multiple times. It will not begin emitting items from the original Stream until theconnectmethod is invoked. -
publishValue(
) → ValueConnectableStream< T> -
Available on Stream<
Convert the current Stream into aT> , provided by the ConnectableStreamExtensions extensionValueConnectableStreamthat can be listened to multiple times. It will not begin emitting items from the original Stream until theconnectmethod is invoked. -
publishValueSeeded(
T seedValue) → ValueConnectableStream< T> -
Available on Stream<
Convert the current Stream into aT> , provided by the ConnectableStreamExtensions extensionValueConnectableStreamthat can be listened to multiple times, providing an initial seeded value. It will not begin emitting items from the original Stream until theconnectmethod is invoked. -
reduce(
T combine(T previous, T element)) → Future< T> -
Combines a sequence of values by repeatedly applying
combine.inherited -
Available on Stream<
Convert the current Stream into a new Stream that can be listened to multiple times. It will automatically begin emitting items when first listened to, and shut down when no listeners remain.T> , provided by the ConnectableStreamExtensions extension -
Available on Stream<
Convert the current Stream into a newT> , provided by the ConnectableStreamExtensions extensionReplayStreamthat can be listened to multiple times. It will automatically begin emitting items when first listened to, and shut down when no listeners remain. -
Available on Stream<
Convert the current Stream into a new ValueStream that can be listened to multiple times. It will automatically begin emitting items when first listened to, and shut down when no listeners remain.T> , provided by the ConnectableStreamExtensions extension -
Available on Stream<
Convert the current Stream into a new ValueStream that can be listened to multiple times, providing an initial value. It will automatically begin emitting items when first listened to, and shut down when no listeners remain.T> , provided by the ConnectableStreamExtensions extension -
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
countdata 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 -
switchMap<
S> (Stream< S> mapper(T value)) → Stream<S> -
Available on Stream<
Converts each emitted item into a Stream using the given mapper function. The newly created Stream will be be listened to and begin emitting items, and any previously created Stream will stop emitting.T> , provided by the SwitchMapExtension extension -
take(
int count) → Stream< T> -
Provides at most the first
countdata events of this stream.inherited -
takeWhile(
bool test(T element)) → Stream< T> -
Forwards data events while
testis 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
streamTransformerto this stream.inherited -
where(
bool test(T event)) → Stream< T> -
Creates a new stream from this stream that discards some elements.
inherited
-
whereNotNull(
) → Stream< T> -
Available on Stream<
Returns a Stream which emits all the non-T?> , provided by the WhereNotNullExtension extensionnullelements of this Stream, in their original emission order.
Operators
-
operator ==(
Object other) → bool -
The equality operator.
inherited