Dart 流

Sink<T>

+ void add(T data);+ void close();

私_StreamController<T>

- int _state = _STATE_INITIAL;

+ operation1(params):returnType- operation2(params)- operation3()

私_AsyncStreamControllerDispatch<T>

私_ControllerSubscription<T>

私_StreamControllerLifecycle<T> _controller;

- void _onResume() ；- void _onPause()- Future<void>? _onCancel()

私_StreamControllerLifecycle<T>

私_SyncBroadcastStreamController<T>

StreamConsumer<S>

+ Future addStream(Stream<S> stream);+ Future close();

私_EventSink<T>

私_BufferingStreamSubscription<T>

- int _state;- _DataHandler<T> _onData;- _DoneHandler _onDone;- Function _onError;- Future? _cancelFuture;

实现StreamSubscription中的方法，维护状态。

StreamController<T>

+ Stream<T> stream ;+ Function() onListen;+ Function() onPause;+ Function() onResume;+ Function() onCancel;+ StreamSink<T> sink;+ bool isClosed;+ bool isPaused;+ bool hasListener;+ bool done;

私_StreamControllerBase<T>

私_EventDispatch<T>

私_SyncStreamControllerDispatch<T>

SynchronousStreamController<T>

Stream<T>

私_AsyncBroadcastStreamController<T>

私_BroadcastSubscription<T>

- _BroadcastSubscription<T>? _next;- _BroadcastSubscription<T>? _previous;

-  bool _expectsEvent(int eventId);- void _toggleEventId();

私_SyncStreamController<T>

+ 混入_SyncStreamControllerDispatch<T>

私_AsyncStreamController<T>

+ 混入_AsyncStreamControllerDispatch<T>

StreamSubscription<T>

+ void onData(void handleData(T data)?);+ void onError(Function? handleError);+ void onDone(void handleDone()?);+ void pause([Future<void>? resumeSignal]);+ void resume();+ Future<void> cancel();+ bool isPaused;

私_BroadcastStreamController<T>

- Function()? onListen- Function()? onCancel- int _state;- _BroadcastSubscription<T>? _firstSubscription;- _BroadcastSubscription<T>? _lastSubscription;

+ Stream<T> get stream => new _BroadcastStream<T>(this);+ StreamSink<T> get sink => new _StreamSinkWrapper<T>(this);+ 实现其他方法

EventSink<T>

StreamSink<S>

+ Future close();+ Future get done;