Bad state: Stream has already been listened to.

[Shruti2208]

I'm trying to separate the UI and the logic by using providers with ChangeNotifier. First round works perfectly fine but when tried to open the module again getting the error : Bad state: Stream has already been listened to. Any idea how to go about this?

[jinyus]

Sounds like you're closing the ReceivePort on dispose(as you should). but you should create a new ReceivePort when reopening the "module" because once you call close on a stream, you can not longer listen to it.

[phuongphally]

I have some issue .

Resolve by add static before method

static void downloadCallback(String id, DownloadTaskStatus status, int progress) 

[febryardiansyah]

I have same issue, i'am using bloc to separate ui and logic. i solved it by creating new ReceivePort instance every bloc called, so i make the port variable late.

  late ReceivePort _port;

  void registerPort() {
    _port = ReceivePort();
    IsolateNameServer.registerPortWithName(
      _port.sendPort,
      'downloader_send_port',
    );
    _port.listen((dynamic data) {
      DownloadTaskStatus status = data[1];
      int progress = data[2];
      emit(state.copyWith(
        progress: progress,
        downloadTaskStatus: status,
      ));
    });
    FlutterDownloader.registerCallback(downloadCallback);
  }