Android, Can't get MediaPlayer class to work

I would like to add sound to an animation that I have created. Everytime the animation starts, supposedly a sound has to start as well, but I can't manage to start the sound.

All is ok with the animation, here's the code piece:

public class TestActivity extends Activity {
AnimationDrawable  anim;
MediaPlayer mp;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    playAnimation(R.id.frameLayout1,R.drawable.anim2,R.raw.bang);
}

public void playAnimation(int FrameLayoutAddress, int animationXMLAdress, int soundAddress)
{
     mp = Medi开发者_开发百科aPlayer.create(this.getApplicationContext(), soundAddress);
     mp.start(); // error here

     FrameLayout imgView = (FrameLayout)findViewById(FrameLayoutAddress);
     imgView.setBackgroundResource(animationXMLAdress);
     anim = (AnimationDrawable) imgView.getBackground();
     imgView.post(new Runnable()
     {       
         @Override
         public void run()
         {
             anim.start();

         }
     });    
}   

}

Can anyone point out my mistake ? Thanks in advance for your time.

You should call mp.prepare() before mp.start(). Also it's suggested to reset the MediaPlayer before calling mp.prepare().