[camera] CameraController.setDescription and dispose don't work as expected #126823
Description
Is there an existing issue for this?
- I have searched the existing issues
- I have read the guide to filing a bug
Steps to reproduce
- Initialize a CameraController
- Set a different CameraDescription via setDescription
- Dispose of the controller
- Initialize a new CameraController
- Observer a ChangeNotifier exception
Expected results
No ChangeNotifier exceptions.
Actual results
E/flutter (12815): Once you have called dispose() on a CameraController, it can no longer be used.
E/flutter (12815): #0 ChangeNotifier.debugAssertNotDisposed.<anonymous closure>
change_notifier.dart:179
E/flutter (12815): #1 ChangeNotifier.debugAssertNotDisposed
change_notifier.dart:186
E/flutter (12815): #2 ChangeNotifier.notifyListeners
change_notifier.dart:382
E/flutter (12815): #3 ValueNotifier.value=
change_notifier.dart:530
E/flutter (12815): #4 CameraController._initializeWithDescription.<anonymous closure>
camera_controller.dart:304
E/flutter (12815): #5 _RootZone.runUnaryGuarded (dart:async/zone.dart:1594:10)
E/flutter (12815): #6 _BufferingStreamSubscription._sendData (dart:async/stream_impl.dart:339:11)
E/flutter (12815): #7 _BufferingStreamSubscription._add (dart:async/stream_impl.dart:271:7)
E/flutter (12815): #8 _SyncBroadcastStreamController._sendData (dart:async/broadcast_stream_controller.dart:377:25)
E/flutter (12815): #9 _BroadcastStreamController.add (dart:async/broadcast_stream_controller.dart:244:5)
E/flutter (12815): #10 Where.whereType.<anonymous closure>
where.dart:21
E/flutter (12815): #11 TransformByHandlers.transformByHandlers.<anonymous closure>.<anonymous closure>
from_handlers.dart:29
E/flutter (12815): #12 _RootZone.runUnaryGuarded (dart:async/zone.dart:1594:10)
E/flutter (12815): #13 _BufferingStreamSubscription._sendData (dart:async/stream_impl.dart:339:11)
E/flutter (12815): #14 _DelayedData.perform (dart:async/stream_impl.dart:515:14)
E/flutter (12815): #15 _PendingEvents.handleNext (dart:async/stream_impl.dart:620:11)
E/flutter (12815): #16 _PendingEvents.schedule.<anonymous closure> (dart:async/stream_impl.dart:591:7)
E/flutter (12815): #17 _microtaskLoop (dart:async/schedule_microtask.dart:40:21)
E/flutter (12815): #18 _startMicrotaskLoop (dart:async/schedule_microtask.dart:49:5)
Code sample
Not providing a code sample since, I think I know where the issue is:
If we look at:
CameraController.setDescription we see the new description is set up by calling _initializeWithDescription.
If we look at _initializeWithDescription, we see _deviceOrientationSubscription is set up through direct assignment and subscription to the CameraPlatform.instance.onDeviceOrientationChanged() stream.
Code:
_deviceOrientationSubscription = CameraPlatform.instance
.onDeviceOrientationChanged()
.listen((DeviceOrientationChangedEvent event) {
value = value.copyWith(
deviceOrientation: event.orientation,
);
});The _deviceOrientationSubscription is never cancelled in case we set up a new description, it is simply reassigned.
My guess would be to simply assign the _deviceOrientationSubscription using ??=.
Screenshots or Video
No response
Logs
No response
Flutter Doctor output
Doctor output
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