import java.io.IOException;
import android.app.Activity;
import android.media.MediaPlayer;
import android.media.MediaPlayer.OnCompletionListener;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
 
import com.atm.R;
 
public class MusicPlayer extends Activity {
	/** Called when the activity is first created. */
	@Override
	public void onCreate(Bundle icicle) {
		super.onCreate(icicle);
		setContentView(R.layout.music_player);
 
		// Find the Button from the xml-file.
		Button cmd_play = (Button) this.findViewById(R.id.cmd_play);
		cmd_play.setOnClickListener(new OnClickListener() {
 
			@Override
			public void onClick(View arg0) {
				MediaPlayer mp = MediaPlayer.create(MusicPlayer.this,
						R.raw.fish);
				try {
					mp.prepare();
				} catch (IllegalStateException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				} catch (IOException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				}
				mp.start();
				// i.e. react on the end of the music-file:
				mp.setOnCompletionListener(new OnCompletionListener() {
 
					// @Override
					public void onCompletion(MediaPlayer arg0) {
						// File has ended !!! Wink
					}
				});
			}
		});
	}
}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
	android:orientation="vertical" android:layout_width="fill_parent"
	android:layout_height="fill_parent">
	<Button android:id="@+id/cmd_play" android:layout_width="fill_parent"
		android:layout_height="wrap_content"
		android:text="Play the music !!!" />
</LinearLayout>