BLoC to BLoC communication example

autocomplete_bloc.dart

class AutocompleteQuery {
  final String query;
  final LatLng location;
  final double radius;

  AutocompleteQuery(this.query, {this.location, this.radius = 3000});
}

class AutocompleteBloc extends BlocBase {
  final _autocompletePlacesInputSubject = PublishSubject<AutocompleteQuery>();

  Sink<AutocompleteQuery> get autocompletePlacesSink =>
      _autocompletePlacesInputSubject.sink;

  AutocompleteBloc() {
    _autocompletePlacesInputSubject
        .debounce((event) => TimerStream(true, Duration(milliseconds: 500)))
        .asyncMap(
          (event) => GeolocationManager.instance
              .getSuggestedPlacesByQuery(
                event.query,
                location: event.location,
                radius: event.radius,
              )
              .catchError((e) => throw (e)),
        )
        .listen(_autocompletePlacesOutputSubject.sink.add, onError: (e) {
      print(e);
      _autocompletePlacesOutputSubject.sink.addError(e);
    });
  }

  final _autocompletePlacesOutputSubject = BehaviorSubject<List<Place>>();
  Stream<List<Place>> get autocompletePlacesStream =>
      _autocompletePlacesOutputSubject.stream;

  @override
  void disposeInstance() {
    _autocompletePlacesInputSubject?.close();
  }
}

places_bloc.dart

class PlacesBloc extends BlocBase implements AutocompleteBloc {
  final PlacesService placesService;
  final AutocompleteBloc _autocompleteBloc;

  PlacesBloc(this.placesService, AutocompleteBloc autocompleteBloc)
      : _autocompleteBloc = autocompleteBloc;

  @override
  Sink<AutocompleteQuery> get autocompletePlacesSink =>
      _autocompleteBloc.autocompletePlacesSink;

  @override
  Stream<List<Place>> get autocompletePlacesStream =>
      _autocompleteBloc.autocompletePlacesStream;

  @override
  void disposeInstance() {
    _autocompleteBloc?.dispose();
  }
}