Transforms a Stream.
When a stream's Stream.transform method is invoked with a StreamTransformer, the stream calls the bind method on the provided transformer. The resulting stream is then returned from the Stream.transform method.
Conceptually, a transformer is simply a function from Stream to Stream that is encapsulated into a class.
It is good practice to write transformers that can be used multiple times.
All other transforming methods on Stream, such as Stream.map, Stream.where or Stream.expand can be implemented using Stream.transform. A StreamTransformer is thus very powerful but often also a bit more complicated to use.
- Implemented by
Constructors
- StreamTransformer(StreamSubscription<T> onListen(Stream<S> stream, bool cancelOnError))
-
Creates a StreamTransformer based on the given
onListencallback.constfactory - StreamTransformer.fromHandlers({void handleData(S data, EventSink<T> sink), void handleError(Object error, StackTrace stackTrace, EventSink<T> sink), void handleDone(EventSink<T> sink) })
-
Creates a StreamTransformer that delegates events to the given functions.
factory
Properties
- hashCode → int
-
The hash code for this object.
read-only, inherited - runtimeType → Type
-
A representation of the runtime type of the object.
read-only, inherited
Operators
-
operator ==(
other) → bool -
The equality operator.
inherited
Methods
-
bind(
Stream<S> stream) → Stream<T> -
Transforms the provided
stream. -
noSuchMethod(
Invocation invocation) → dynamic -
Invoked when a non-existent method or property is accessed.
inherited -
toString(
) → String -
Returns a string representation of this object.
inherited