Crash due to PlayerService

[tobiasKaminsky]

Steps to reproduce

1. delete a file
2. see

2020-09-08 07:20:21.303 com.nextcloud.client E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.nextcloud.client, PID: 10750
    android.app.RemoteServiceException: Context.startForegroundService() did not then call Service.startForeground(): ServiceRecord{a08f83f u0 com.nextcloud.client/.media.PlayerService}
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1945)
        at android.os.Handler.dispatchMessage(Handler.java:107)
        at android.os.Looper.loop(Looper.java:214)
        at android.app.ActivityThread.main(ActivityThread.java:7356)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:930)

@ezaquarii this happens on latest dev, and it seems that it is from your foreground fix:
Upon file removed event, FileDisplayActivity onRemoveFileOperationFinish is called and this calls tryStopPlaying.

PR was #6798

[tobiasKaminsky]

Doc from context.startForegroundService(i) says:

Similar to startService(Intent), but with an implicit promise that the Service will call startForeground(int, android.app.Notification) once it begins running.

And this is not true if we only try to stop playback as then directly onStop() is called in PlayerService.
As startForeground is showing a notification, I do not want to show it, and then immediately stop player.

[ezaquarii]

I'll look into this.

[tobiasKaminsky]

#6908 I wrote a (failing) test for this.

[ezaquarii]

@tobiasKaminsky this will be very handy.

[ezaquarii]

@tobiasKaminsky

I need to think a bit more about the possible fix. On newer API levels, interacting with services in the background is limited by the OS. Quite a lot of our code assumes that you can ping a background service at will.

I need to take a closer look at the player state machine.

I know that the previous PR #6798 addressed a similar issue in different code path, however we can consider what is the lesser evil here - keeping the fix or backing it out - by comparing the severity of those 2 bugs. I have no access to crash logs, but feel free to back out #6798 if you feel that previous bug was less serious.

[AndyScherzinger]

Also see #7189 (comment)

[AndyScherzinger]

Also see #7187 (comment)

[AndyScherzinger]

Also see #7191 (comment)

[XueSheng-GIT]

Still can't play videos in 3.14.0 RC2 without crash. Will this be fixed for 3.14.0 final?

[Siggi0904]

Still crashes with RC2.

[tobiasKaminsky]

There is an APK file in PR #7340, which you can install in parallel to your existing Nextcloud app.
It would be great if you can verify the fix.

[Siggi0904]

Auch mit der 3.14.0 stable crasht die App.

Fehlerlog:
`********** CAUSE OF ERROR **********
android.app.RemoteServiceException: Context.startForegroundService() did not then call Service.startForeground(): ServiceRecord{415238b u0 com.nextcloud.client/.media.PlayerService}
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2038)
at android.os.Handler.dispatchMessage(Handler.java:107)
at android.os.Looper.loop(Looper.java:214)
at android.app.ActivityThread.main(ActivityThread.java:7682)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:516)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:950)

********** APP INFORMATION **********
ID: com.nextcloud.client
Version: 30140090
Build flavor: gplay

********** DEVICE INFORMATION **********
Brand: OnePlus
Device: OnePlus6
Model: ONEPLUS A6003
Id: QKQ1.190716.003
Product: OnePlus6

********** FIRMWARE **********
SDK: 29
Release: 10
Incremental: 2010042216`

[tobiasKaminsky]

Will be fixed with #7340

[Siggi0904]

Error still exists.
See: #7470

[tobiasKaminsky]

This should be fixed in 3.14.1 RC2 coming today. You can test it via play store beta program.
If not, please re-open.