movie_repository.dart

final LoadingStatus _upcomingMoviesLoadingStatus = LoadingStatus();
DataStream<List<ContentDetailData>> observeDetailedUpcoming() =>
    _movieDao.observeAllUpcoming().asyncMap(getDetailsFromDb).combineLatest<bool,
        StreamData<List<ContentDetailData>>>(_upcomingMoviesLoadingStatus.listen(), 
        (data, isLoading) {
          if (isLoading) {
            return LoadingData(data);
          }
          return ReadyData(data);
        });