Error: Bad state: Cannot add new events after calling close with just_audio and riverpod

Question

I'm currently working on a Flutter application using the just_audio and flutter_riverpod packages. In my project, I've encountered an issue where I get an error message saying "Error: Bad state: Cannot add new events after calling close" originating from the just_audio package.

This error arises when I click on the alarm sound button.

The error occurs within the following function:

Future<void> playSound() async {
  if (!_isDisposed) {
    final selectedSound = ref.watch(selectedSoundProvider.notifier).state;
    await _audioPlayer.setAsset(selectedSound.path); // Error here
    _audioPlayer.play();
  }
}

I've tried to debug the issue, but I'm having difficulty understanding the source of the problem. I suspect that it might have something to do with the lifecycle of the stream in the just_audio package.

Here are the relevant parts of my code:

timer_notifier.dart:

class TimerNotifier extends StateNotifier<int> {
  ...
  Future<void> playSound() async {
    if (!_isDisposed) {
      final selectedSound = ref.watch(selectedSoundProvider.notifier).state;
      await _audioPlayer.setAsset(selectedSound.path); // Error here
      _audioPlayer.play();
    }
  }
  
  @override
  void dispose() {
    print('dispose is being called');
    _mounted = false;
    _timer?.cancel();
    _isDisposed = true;
    _audioPlayer.dispose();
    super.dispose();
  }
  ...
}

settings_page.dart:

class SettingsPage extends ConsumerWidget {
  ...
  Widget build(BuildContext context, WidgetRef ref) {
    return Scaffold(
      ...
             ListTile(
  title: Text('Alarm Sound'),
  trailing: Row(
    mainAxisSize: MainAxisSize.min,
    children: ref.watch(soundListProvider).map((sound) {
      return Padding(
        padding: const EdgeInsets.all(2.0),
        child: ElevatedButton(
          onPressed: () async {
            ref.read(selectedSoundProvider.notifier).state = sound;
            await ref.read(timerNotifierProvider.notifier).playSound();
          },
          child: Text(sound.friendlyName),
        ),
      );
    }).toList(),
  ),
),
  ...
}

Could anyone help me understand the issue and guide me step-by-step on where to make the necessary changes to resolve this problem? Any help would be much appreciated.

Thank you!

score 1 · Accepted Answer · answered Jul 12 '23 at 05:09

The problem is in this part of the code:

Future<void> playSound() async {
  if (!_isDisposed) { //     ⬇here⬇
    final selectedSound = ref.read(selectedSoundProvider.notifier).state;
    await _audioPlayer.setAsset(selectedSound.path); // Error here
    _audioPlayer.play();
  }
}

You should use ref.read in callbacks and lifecycle methods like initState().

Error: Bad state: Cannot add new events after calling close with just_audio and riverpod

1 Answers1