I'm currently developing a simple media player using a client/service approach using MediaBrowser compat from the Android support library.
I'm getting the following exception:
FATAL EXCEPTION: main
Process: valdivia.peter.inclubooks, PID: 32383
java.lang.NullPointerException: Attempt to invoke virtual method 'int android.support.v4.media.session.PlaybackStateCompat.getState()' on a null object reference
at valdivia.peter.inclubooks.activities.MostrarAudiolibroActivity$3.onClick(MostrarAudiolibroActivity.java:118)
at android.view.View.performClick(View.java:5201)
at android.view.View$PerformClick.run(View.java:at android.os.Handler.handleCallback(Handler.java:
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5443)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:728)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
What I understand is that either the controller or the playbackstate are null, so obviously it can't return the int representing the player's state.
Here are how I create the controller on the client activity in the onConnected() method from the MediaBrowser callback:
@Override
public void onConnected() {
super.onConnected();
Log.d(tag,"Conecté al servicio");
Log.d(tag,"token:" + mMediaBrowser.getSessionToken().toString());
try{
controller = new MediaControllerCompat(getApplicationContext(),mMediaBrowser.getSessionToken());
}catch(RemoteException exception){
Log.d(tag,"Remote Exception al crear el Media Controller");
Toast.makeText(getApplicationContext(),"Error al crear los controles de la sesión",Toast.LENGTH_LONG).show();
return;
}
controller.registerCallback(mControllerCallback);
MediaControllerCompat.setMediaController(MostrarAudiolibroActivity.this,controller);
buildTransportControls();
}
And here how I build the transport controls:
private void buildTransportControls() {
ImageButton mBotonPausa = (ImageButton) findViewById(R.id.mostrar_audiolibro_playpause);
mBotonPausa.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
MediaControllerCompat mediaControllerCompat = MediaControllerCompat.getMediaController(MostrarAudiolibroActivity.this);
int estado = mediaControllerCompat.getPlaybackState().getState();
if(estado == PlaybackStateCompat.STATE_PLAYING){
MediaControllerCompat.getMediaController(MostrarAudiolibroActivity.this).getTransportControls().pause();
}else if (estado == PlaybackStateCompat.STATE_PAUSED){
MediaControllerCompat.getMediaController(MostrarAudiolibroActivity.this).getTransportControls().play();
}else{
Bundle extras = new Bundle();
extras.putString("titulo",MostrarAudiolibroActivity.this.audiolibro.getTitulo());
extras.putString("autor",MostrarAudiolibroActivity.this.audiolibro.getAutor());
MediaControllerCompat.getMediaController(MostrarAudiolibroActivity.this).getTransportControls().playFromUri(Uri.parse(MostrarAudiolibroActivity.this.audiolibro.getLinkAudiolibro()),extras);
Log.d(tag,"Voy a tratar de abrir el audio");
}
}
});
ImageButton mBotonReiniciar = (ImageButton) findViewById(R.id.mostrar_audiolibro_reiniciar);
mBotonReiniciar.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
MediaControllerCompat.getMediaController(MostrarAudiolibroActivity.this).getTransportControls().seekTo(0);
//MediaControllerCompat.getMediaController(MostrarAudiolibroActivity.this).getTransportControls().play();
}
});
}
What I'm doing wrong. Thanks in advance.
The call to
MediaControllerCompat.getPlaybackState()
can and is returning null. The documentation for that method says that returning null is a possibility. You have to alter your code to allow for that possibility.To be more specific, the line:
Has to be split in multiple parts: