streams_8.dart

class ApplicationBloc implements BlocBase {
  ///
  /// Synchronous Stream to handle the provision of the movie genres
  ///
  final StreamController<List<MovieGenre>?> _syncController = StreamController<List<MovieGenre>?>.broadcast();
  Stream<List<MovieGenre>?> get outMovieGenres => _syncController.stream;

  ///
  /// Stream to handle a fake command to trigger the provision of the list of MovieGenres via a Stream
  ///
  final StreamController<List<MovieGenre>?> _cmdController = StreamController<List<MovieGenre>?>.broadcast();
  StreamSink get getMovieGenres => _cmdController.sink;

  ApplicationBloc() {
    //
    // If we receive any data via this sink, we simply provide the list of MovieGenre to the output stream
    //
    _cmdController.stream.listen((_){
      _syncController.sink.add(UnmodifiableListView<MovieGenre>(_genresList.genres));
    });
  }

  void dispose(){
    _syncController.close();
    _cmdController.close();
  }

  MovieGenresList? _genresList;
}

// Example of external call
BlocProvider.of<ApplicationBloc>(context).getMovieGenres.add(null);