IllegalStateException about wrong thread Player access upon MediaSessionService connection

[bubenheimer]

Media3 Version

Media3 1.0.0

Devices that reproduce the issue

Android emulator

Devices that do not reproduce the issue

No response

Reproducible in the demo app?

Not tested

Reproduction steps

I have a custom player class extending SimpleBasePlayer, using a non-main looper. It is part of a MediaSessionService that runs in a separate process from the client.

The service crashes, complaining about the looper, apparently when the client connects. I suspect this may be a bug in media3, I do not see any any of my own code in the stacktrace. I also do not see a way to influence the media3 behavior here, short of possibly implementing my own notification scheme, running the player on the main looper, or not offering a Timeline right away.

The only place on the service side where I specify the non-main looper is in the SimpleBasePlayer constructor. I have not seen another applicable API to customize the looper.

I assume the stacktrace will be sufficient to pinpoint the logic error here.

Expected result

No service crash when connecting to MediaSessionService.

Actual result

The MediaSessionService crashes:

RuntimeException while executing runnable androidx.media3.session.MediaNotificationManager$$ExternalSyntheticLambda1@6f7d357 with executor androidx.media3.session.MediaNotificationManager$$ExternalSyntheticLambda2@633ae44
java.lang.IllegalStateException: Player is accessed on the wrong thread.
Current thread: 'main'
Expected thread: 'OffMainLooper'
See https://exoplayer.dev/issues/player-accessed-on-wrong-thread
    at androidx.media3.common.SimpleBasePlayer.verifyApplicationThreadAndInitState(SimpleBasePlayer.java:3360)
    at androidx.media3.common.SimpleBasePlayer.getCurrentTimeline(SimpleBasePlayer.java:2415)
    at androidx.media3.session.MediaNotificationManager.shouldShowNotification(MediaNotificationManager.java:256)
    at androidx.media3.session.MediaNotificationManager.access$000(MediaNotificationManager.java:54)
    at androidx.media3.session.MediaNotificationManager$MediaControllerListener.onConnected(MediaNotificationManager.java:275)
    at androidx.media3.session.MediaNotificationManager.lambda$addSession$1$androidx-media3-session-MediaNotificationManager(MediaNotificationManager.java:103)
    at androidx.media3.session.MediaNotificationManager$$ExternalSyntheticLambda1.run(Unknown Source:8)
    at androidx.media3.common.util.Util.postOrRun(Util.java:607)
    at androidx.media3.session.MediaNotificationManager.lambda$new$0(MediaNotificationManager.java:80)
    at androidx.media3.session.MediaNotificationManager$$ExternalSyntheticLambda2.execute(Unknown Source:2)
    at com.google.common.util.concurrent.AbstractFuture.executeListener(AbstractFuture.java:1270)
    at com.google.common.util.concurrent.AbstractFuture.complete(AbstractFuture.java:1038)
    at com.google.common.util.concurrent.AbstractFuture.set(AbstractFuture.java:783)
    at androidx.media3.session.MediaControllerHolder.maybeSetFutureResult(MediaControllerHolder.java:62)
    at androidx.media3.session.MediaControllerHolder.onAccepted(MediaControllerHolder.java:52)
    at androidx.media3.session.MediaController.notifyAccepted(MediaController.java:1849)
    at androidx.media3.session.MediaControllerImplBase.onConnected(MediaControllerImplBase.java:2163)
    at androidx.media3.session.MediaControllerStub.lambda$onConnected$0(MediaControllerStub.java:87)
    at androidx.media3.session.MediaControllerStub$$ExternalSyntheticLambda6.run(Unknown Source:2)
    at androidx.media3.session.MediaControllerStub.lambda$dispatchControllerTaskOnHandler$11(MediaControllerStub.java:301)
    at androidx.media3.session.MediaControllerStub$$ExternalSyntheticLambda11.run(Unknown Source:4)
    at android.os.Handler.handleCallback(Handler.java:942)
    at android.os.Handler.dispatchMessage(Handler.java:99)
    at android.os.Looper.loopOnce(Looper.java:201)
    at android.os.Looper.loop(Looper.java:288)
    at android.app.ActivityThread.main(ActivityThread.java:7872)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:548)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:936)

Media

N/A

Bug Report

• You will email the zip file produced by adb bugreport to dev.exoplayer@gmail.com after filing this issue.

[tonihei]

Thanks for reporting! We identified the underlying issue and can provide a fix for it in the next bugfix release.

[bubenheimer]

1.0.1 does fix this issue. Thank you!