How to fix NoClassDefFoundError: android.media.session.MediaSessionManager

Question

I made an app it run perfectly in api 20+ but for android version 4.4 and less it is getting crashed with error NoClassDefFoundError: android.media.session.MediaSessionManager this is the stack trace that i am getting in the developer console .

java.lang.NoClassDefFoundError: android.media.session.MediaSessionManager
at beatbox.neelay.beatbox.MediaService.initMediaSession(MediaService.java:634)
at beatbox.neelay.beatbox.MediaService.onStartCommand(MediaService.java:170)
at android.app.ActivityThread.handleServiceArgs(ActivityThread.java:2913)
at android.app.ActivityThread.access$2100(ActivityThread.java:151)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1442)
at android.os.Handler.dispatchMessage(Handler.java:110)
at android.os.Looper.loop(Looper.java:193)
at android.app.ActivityThread.main(ActivityThread.java:5339)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:828)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:644)
at dalvik.system.NativeStart.main(Native Method)

All I am able to understand from this is the error is in the initMediaSession method .this is my initMediaSession method

private void initMediaSession() throws RemoteException {
    if (mediaSessionManager != null) return; //mediaSessionManager exists

    mediaSessionManager = (MediaSessionManager) getSystemService(Context.MEDIA_SESSION_SERVICE);
    // Create a new MediaSession
    mediaSession = new MediaSessionCompat(getApplicationContext(), "AudioPlayer");
    //Get MediaSessions transport controls
    transportControls = mediaSession.getController().getTransportControls();
    //set MediaSession -> ready to receive media commands
    mediaSession.setActive(true);
    //indicate that the MediaSession handles transport control commands
    // through its MediaSessionCompat.Callback.
    mediaSession.setFlags(MediaSessionCompat.FLAG_HANDLES_TRANSPORT_CONTROLS);

    //Set mediaSession's MetaData
    updateMetaData();
    // passing the data


    // Attach Callback to receive MediaSession updates
    mediaSession.setCallback(new MediaSessionCompat.Callback() {
        // Implement callbacks
        @Override
        public void onPlay() {
            super.onPlay();
            messagesent();
            a = false;
            resumeMedia();
            buildNotification(PlaybackStatus.PLAYING);
        }

        @Override
        public void onPause() {
            super.onPause();
            messagesent();
            a = true;
            pauseMedia();
            buildNotification(PlaybackStatus.PAUSED);
        }

        @Override
        public void onSkipToNext() {
            super.onSkipToNext();

            skipToNext();
            updateMetaData();
            buildNotification(PlaybackStatus.PLAYING);
        }

        @Override
        public void onSkipToPrevious() {
            super.onSkipToPrevious();

            skipToPrevious();
            updateMetaData();
            buildNotification(PlaybackStatus.PLAYING);
        }

        @Override
        public void onStop() {
            super.onStop();
            removeNotification();
            //Stop the service
            pauseMedia();
            messagesent();
            stopSelf();
        }

        @Override
        public void onSeekTo(long position) {
            super.onSeekTo(position);
        }
    });
}

I dont understand why it is getting crashend for 4.4 and less devices and how i can fix this .I googled and got this but this post dont tell how tofix this.

Answer 1

I am also following the same tutorial and had same issue. I found the solution to this. Simply check if your SDK >21 then only use method initMediaSession();

Answer 2

MediaSessionManager was only added in api 21 (5.0)

If it's absolutely necessary to use it then you can set your min sdk to 21 or check your build number with:

android.os.Build.VERSION.SDK

and not call this service with devices with lower sdks

Answer 3

It seems that the reason may be due to multidex. Check your apk method count at Get Method Count

You can enable multidex by adding dependency

compile 'com.android.support:multidex:1.0.1'

then enable it in config

 defaultConfig {
        multiDexEnabled true      
    }

add following snippet in android section of your

dexOptions {
        javaMaxHeapSize "4g"
        preDexLibraries false
    }

    afterEvaluate {
        tasks.matching {
            it.name.startsWith('dex')
        }.each { dx ->
            if (dx.additionalParameters == null) {
                dx.additionalParameters = []
            }
            dx.additionalParameters += '--multi-dex'

            // this is optional
            dx.additionalParameters += "--main-dex-list=$projectDir/multidex.keep".toString()
        }
    }

    compileOptions {
        incremental false
    }