How to play video and audio on Android Part 2.


SDK Version: 
M3

In this part, I'm going to focus on MediaPlayer. I'm going to show you, how to stop it properly, and how to create a media player more easily.
The default behavior is the same, with every activity, after onPause and onStop, if the activity is not destroyed, it will continue to run in the background, until it is killed so the system can free up the memory it is using. So until the activity is destroyed, the mediaplayer will continue to occupy space in the phones memory.

  1. private MediaPlayer mp;
  2.  
  3. public void onCreate(Bundle savedInstanceState) {
  4.     super.onCreate(savedInstanceState);
  5.     mp=new MediaPlayer();
  6.     audioPlayer(context,uri);
  7. }
  8.  
  9. public void audioPlayer(Context context,Uri uri){
  10.     mp= MediaPlayer.create(context, uri);
  11.     mp.start();
  12. }

From the official docs:
"public static MediaPlayer create (Context context, Uri uri)
Convenience method to create a MediaPlayer for a given Uri. On success, prepare() will already have been called and must not be called again.
When done with the MediaPlayer, you should call release(), to free the resources. If not released, too many MediaPlayer instances will result in an exception."

I have yet to get an exception from mediaplayer, but to make sure it won't happen, don't forget to realese(), at least in onDestroy()!

  1. @Override
  2. protected void onPause() {
  3.     super.onPause();
  4.     if(mp.isPlaying()){ //you need to check if it is playing first, or you might get a null pointer exception!
  5.         mp.stop();
  6.     }
  7. }

Depending on your needs, you can put the mp.stop() in the onPause part, so if the activity goes to the background for whatever reason, it will only pause the playback, and it can continue it in onResume(). Just put mp.play() in onResume().

  1. @Override
  2.  public void onDestroy(){
  3.  super.onDestroy();
  4.     mp.release();
  5.  }

If you don't release the media player in the onDestroy part, it will continue to be in the memory, after the activity is stopped. The OS will handle this issue for you if it runs out of memory, but it's nicer, if You do it, so the OS will run out of memory later (much later in case of huge files).

As an alternative, you could set up an onCompletionListener, so when the media playback is done, it will release the media player.

  1. mp.setOnCompletionListener(new OnCompletionListener(){
  2.     @Override
  3.     public void onCompletion(MediaPlayer mp) {
  4.         mp.release();
  5.     }
  6.  });