StreamController<T> class Null safety

A controller with the stream it controls.

This controller allows sending data, error and done events on its stream. This class can be used to create a simple stream that others can listen on, and to push events to that stream.

It's possible to check whether the stream is paused or not, and whether it has subscribers or not, as well as getting a callback when either of these change.

Implemented types
Implementers
Available Extensions

Constructors

StreamController({void onListen()?, void onPause()?, void onResume()?, FutureOr<void> onCancel()?, bool sync = false})
A controller with a stream that supports only one single subscriber. [...]
factory
StreamController.broadcast({void onListen()?, void onCancel()?, bool sync = false})
A controller where stream can be listened to more than once. [...]
factory

Properties

done Future
A future which is completed when the stream controller is done sending events. [...]
read-only, override
hashCode int
The hash code for this object. [...]
read-only, inherited
hasListener bool
Whether there is a subscriber on the Stream.
read-only
isClosed bool
Whether the stream controller is closed for adding more events. [...]
read-only
isPaused bool
Whether the subscription would need to buffer events. [...]
read-only
onCancel ↔ (FutureOr<void> Function?()?)
The callback which is called when the stream is canceled. [...]
read / write
onListen ↔ (void Function?()?)
The callback which is called when the stream is listened to. [...]
read / write
onPause ↔ (void Function?()?)
The callback which is called when the stream is paused. [...]
read / write
onResume ↔ (void Function?()?)
The callback which is called when the stream is resumed. [...]
read / write
runtimeType Type
A representation of the runtime type of the object.
read-only, inherited
sink StreamSink<T>
Returns a view of this object that only exposes the StreamSink interface.
read-only
stream Stream<T>
The stream that this controller is controlling.
read-only

Methods

add(T event) → void
Sends a data event. [...]
override
addError(Object error, [StackTrace? stackTrace]) → void
Sends or enqueues an error event. [...]
override
addStream(Stream<T> source, {bool? cancelOnError}) Future
Receives events from source and puts them into this controller's stream. [...]
override
close() Future
Closes the stream. [...]
override
noSuchMethod(Invocation invocation) → dynamic
Invoked when a non-existent method or property is accessed. [...]
inherited
toString() String
A string representation of this object. [...]
inherited

Operators

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