dart:async
StreamTransformer<S, T> class
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.
- Implementers
Constructors
- StreamTransformer(StreamSubscription<T> onListen(Stream<S> stream, bool cancelOnError))
const
factory
- Creates a StreamTransformer based on the given
onListen
callback. [...] - StreamTransformer.fromBind(Stream<T> bind(Stream<S>))
factory
- Creates a StreamTransformer based on a
bind
callback. [...] - StreamTransformer.fromHandlers({void handleData(S data, EventSink<T> sink), void handleError(Object error, StackTrace stackTrace, EventSink<T> sink), void handleDone(EventSink<T> sink) })
factory
- Creates a StreamTransformer that delegates events to the given functions. [...]
Properties
- hashCode → int
read-only, inherited
- The hash code for this object. [...]
- runtimeType → Type
read-only, inherited
- A representation of the runtime type of the object.
Methods
- bind(Stream<S> stream) → Stream<T>
- Transforms the provided
stream
. [...] - cast<RS, RT>() → StreamTransformer<RS, RT>
- Provides a
StreamTransformer<RS, RT>
view of this stream transformer. [...] - noSuchMethod(Invocation invocation) → dynamic
inherited
- Invoked when a non-existent method or property is accessed. [...]
- toString() → String
inherited
- Returns a string representation of this object.
Operators
- operator ==(dynamic other) → bool
inherited
- The equality operator. [...]
Static Methods
- castFrom<SS, ST, TS, TT>(StreamTransformer<SS, ST> source) → StreamTransformer<TS, TT>
- Adapts
source
to be a StreamTransformer<TS, TT>
. [...]