Android SurfaceView video player Black screen

Android SurfaceView video player Black screen

I'm new at android and i'm trying to make a simple video player using
surfaceView.
My xml:
<?xml version="1.0" encoding="utf-8"?>
<AbsoluteLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="800dp"
android:layout_height="800dp"
android:orientation="vertical" >
<SurfaceView
android:id="@+id/surfaceview"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
/>
</AbsoluteLayout>
My code:
public class MainActivity extends Activity
implements SurfaceHolder.Callback {
MediaPlayer mediaPlayer;
SurfaceView surfaceView;
SurfaceHolder surfaceHolder;
@Override
protected void onCreate(Bundle savedInstanceState)
{
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
getWindow().setFormat(PixelFormat.UNKNOWN);
surfaceView = (SurfaceView)findViewById(R.id.surfaceview);
surfaceHolder = surfaceView.getHolder();
surfaceHolder.addCallback(this);
surfaceHolder.setFixedSize(176, 144);
surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
mediaPlayer = new MediaPlayer();
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width,
int height) {
// TODO Auto-generated method stub
}
@Override
public void surfaceCreated(SurfaceHolder holder) {
// TODO Auto-generated method stub
mediaPlayer.setDisplay(holder);
play();
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
// TODO Auto-generated method stub
}
void play(){
try {
mediaPlayer.setDataSource("android.resource://"+getPackageName()+"/"+R.raw.video);
mediaPlayer.prepare();
} catch (IllegalArgumentException e) {
e.printStackTrace();
} catch (IllegalStateException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
mediaPlayer.start();
}
My problem is that the video dont start only apears a black screen no
video or sound. I'm doing something wrong? Any ideas? Thx for the help.