异常 java.lang.NoClassDefFoundError

Question

I'm new to app development. I got this error in my published app on Play store. Google play console tracked this below error in the crash details section. Because of this error my app is getting bad behaviour status on play console. This error came on Android SDK 25 and below. Can anyone please show the proper full method for audio focus request in a media player where audio is played and paused from the main screen and notification area. Also the audio is stored in the raw folder locally.

 Exception java.lang.NoClassDefFoundError: Failed resolution of: Landroid/media/AudioFocusRequest$Builder;
  at com.onestopstudio.sankatmochanhanuman.SankatMochanHanuman.onCreate (SankatMochanHanuman.java:197)
  at android.app.Activity.performCreate (Activity.java:6977)
  at android.app.Instrumentation.callActivityOnCreate (Instrumentation.java:1126)
  at android.app.ActivityThread.performLaunchActivity (ActivityThread.java:2946)
  at android.app.ActivityThread.handleLaunchActivity (ActivityThread.java:3064)
  at android.app.ActivityThread.-wrap14 (ActivityThread.java)
  at android.app.ActivityThread$H.handleMessage (ActivityThread.java:1659)
  at android.os.Handler.dispatchMessage (Handler.java:102)
  at android.os.Looper.loop (Looper.java:154)
  at android.app.ActivityThread.main (ActivityThread.java:6816)
  at java.lang.reflect.Method.invoke (Method.java)
  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run (ZygoteInit.java:1565)
  at com.android.internal.os.ZygoteInit.main (ZygoteInit.java:1453)
Caused by java.lang.ClassNotFoundException:
  at dalvik.system.BaseDexClassLoader.findClass (BaseDexClassLoader.java:56)
  at java.lang.ClassLoader.loadClass (ClassLoader.java:380)
  at java.lang.ClassLoader.loadClass (ClassLoader.java:312)

Here is the code below I'm using for audio focus request. This code is also shown in GeekForGeeks How to Manage Audio Focus in Android? question. Here is the link for GeekForGeeks topic page:- https://www.geeksforgeeks.org/how-to-manage-audio-focus-in-android

 audioManager = (AudioManager) getSystemService(Context.AUDIO_SERVICE);
    playbackAttributes = new AudioAttributes.Builder()
            .setUsage(AudioAttributes.USAGE_MEDIA)
            .setContentType(AudioAttributes.CONTENT_TYPE_MUSIC)
            .build();

    AudioFocusRequest focusRequest = new AudioFocusRequest.Builder(AudioManager.AUDIOFOCUS_GAIN)
            .setAudioAttributes(playbackAttributes)
            .setAcceptsDelayedFocusGain(true)
            .setOnAudioFocusChangeListener(audioFocusChangeListener)
            .build();
    audioFocusRequest = audioManager.requestAudioFocus(focusRequest);
    audioManager.abandonAudioFocus(audioFocusChangeListener);

Answer 1

You should use AudioFocusRequest.Builder on Android 8.0 (API level 26) and higher or try to use compat version: add this to your build.gradle :

dependencies {
   implementation "androidx.media:media:1.6.0"
}

And use AudioFocusRequestCompat.Builder instead of AudioFocusRequest.Builder