Agfdhyk

I am using the BLoC pattern as described at the Google IO talk.

I have a simple BLoC which is used to display a alert in the UI whenever a string is added to messageSink:

class AlertBloc {

  final _message = BehaviorSubject<String>();



  AlertBloc() {}



  Stream<String> get message => _message.stream;



  Sink<String> get messageSink => _message.sink;



  void dispose() {

    _message.close();   }

}

Elsewhere in the app, I have another BLoC which needs to add a string to messageSink, when a certain condition is met.

I noticed it is not a good idea to provide the whole BLoC from the Google I/O repo for the talk, and they provide advice for connecting a stream from a BLoC to another BLoC sink:

Note that we are not providing [CartBloc] to the
[ProductSquareBloc] directly, although it would be easier to
implement. BLoCs should not depend on other BLoCs (separation of
concerns). They can only communicate with each other using
streams. In this case, the [CartBloc.items] output plugs into the
[ProductSquareBloc.cartItems] input.

My question is how to connect a sink from a BLoC to another BLoC stream?

The exact same way as you'd do with streams: Passing it as parameter

class Bloc {

  final Sink<int> _external;



  Bloc(this._external);

}