Unresponsive Media Notification

[intermarc]

The media notification of the app sometimes becomes unresponsive when the app is closed in the background (by the user or the system). This bug affects both the current production release 1.6.2 (96542d0) and the branch playback_resumption (9393e42).

The issue is complicated because it appears to affect different API levels differently. Details follow in the comments below.

The problem can be re-produced by following these steps:

1. Start the app and play a talk
2. Pause the talk
3. Switch to the home screen and/or a different app
4. Stop the app by dismissing it from the recent apps list
5. The media notification remains active, but the play/pause button is unresponsive

[intermarc]

In v1.6.2 (96542d0), the broken media notification affects API level 34 as illustrated in this video captured from the emulator in Android Studio:

API34_features_anr_Screen_recording_20240421_134311.mp4

By contrast, API levels 30 and 33 do not seem to be affected. In these cases, the work-around of commit c980064 does what it should: the MediaSessionService is stopped when the app stops such that we aren't left with a broken notification. Here is another video captured from the emulator with API level 33:

API33_features_anr_Screen_recording_20240421_135841.mp4

[intermarc]

The branch playback_resumption implements changes that should make this work-around unnecessary. It implements the playback resumption feature described here.

Media3 includes an API to enable users to resume playback after an app has terminated and even after the device has been restarted.

I haven't been able to get this new feature to work yet, though.

On API level 34, the behavior is the same as in the v1.6.2 release:

API34_Screen_recording_20240421_103146.mp4

The mediaserver logs show the following error when the play button of the notification is pressed:

2024-04-21 10:31:19.983 444-5428 mediaserver mediaserver E unlinkToDeath: removed reference to death recipient but unlink failed: DEAD_OBJECT
2024-04-21 10:31:20.009 444-1023 ResourceManagerMetrics mediaserver I pushConcurrentUsageReport: No Video Codec Entry for Application[pid(2083): uid(10185)]
2024-04-21 10:31:20.010 444-1023 ResourceManagerMetrics mediaserver I pushConcurrentUsageReport: Concurrent Codec Usage Report for the Process[pid(2083): uid(10185)] is Peak { AudioDec[ SW: 1 ] } Peak Pixels: 0
2024-04-21 10:31:20.018 444-5428 IPCThreadState mediaserver E attemptIncStrongHandle(3): Not supported

This seems to be a known issue with API level 34.

[intermarc]

In API level 33, the behavior of the playback_resumption branch is the same as in API level 34, but I can't find any error messages in the log.

[intermarc]

In API level 30, behavior of the playback_resumption branch is the same as in API levels 33 and 34. The app log shows the following error:

2024-04-21 10:56:30.876 7535-7535 PlaybackService org.dharmaseed.android D entered onPlaybackResumption
2024-04-21 10:56:39.317 7535-7535 PlaybackService org.dharmaseed.android D entered onPlaybackResumption
2024-04-21 10:56:40.652 7535-7535 ExoPlayerImpl org.dharmaseed.android I Release 5ea3391 [AndroidXMedia3/1.3.0] [generic_x86_arm, sdk_gphone_x86, Google, 30] [media3.common, media3.exoplayer, media3.decoder, media3.session]
--------- beginning of crash
2024-04-21 10:56:40.659 7535-7535 AndroidRuntime org.dharmaseed.android D Shutting down VM
2024-04-21 10:56:40.663 7535-7535 AndroidRuntime org.dharmaseed.android E FATAL EXCEPTION: main
Process: org.dharmaseed.android, PID: 7535
android.app.RemoteServiceException: Context.startForegroundService() did not then call Service.startForeground(): ServiceRecord{9193584 u0 org.dharmaseed.android/.PlaybackService}
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2005)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loop(Looper.java:223)
at android.app.ActivityThread.main(ActivityThread.java:7656)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:592)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:947)

Note that the debug messages near the top show that the onPlaybackResumption handler was entered, which does not seem to be the case for API levels 33 and 34. The fact that it was entered twice is because I pressed the play button twice, as shown here:

API30_Screen_recording_20240421_105645.mp4