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dartflutterdispose

Check if Stateless widget is disposed in flutter


When my stateless widget built I play some sounds in sequence order by using this code:

await _audioPlayer.play(contentPath1, isLocal: true);
await Future.delayed(Duration(seconds: 4));
await _audioPlayer.play(contentPath2, isLocal: true);
await Future.delayed(Duration(seconds: 4));
await _audioPlayer.play(contentPath3, isLocal: true);

when the user closes the current widget before finish playing the sounds, The sounds still work even after closing the current route by using this code:

Navigator.pop(context);

my workaround is to use a boolean variable to indicate if the closing action has done.

Playing sound code:

await _audioPlayer.play(contentPath1, isLocal: true);
if (closed) return;
await Future.delayed(Duration(seconds: 4));
if (closed) return;
await _audioPlayer.play(contentPath2, isLocal: true);
if (closed) return;
await Future.delayed(Duration(seconds: 4));
if (closed) return;
await _audioPlayer.play(contentPath3, isLocal: true);

Closing the current widget:

closed = true;
_audioPlayer.stop();

Are there a better way to stop the async methods if my widget closed?


Solution

  • If you change your widget to a StatefulWidget then you can have a function like the following:

    void _playSounds() {
      await _audioPlayer.play(contentPath1, isLocal: true);
      await Future.delayed(Duration(seconds: 4));
      if (!mounted) return;
    
      await _audioPlayer.play(contentPath2, isLocal: true);
      await Future.delayed(Duration(seconds: 4));
      if (!mounted) return;
    
      await _audioPlayer.play(contentPath3, isLocal: true);
    }
    

    and then in the dispose method just dispose of the player:

    @override
    void dispose() {
      _audioPlayer?.dispose();
      super.dispose();
    }