چطور می تونم به این پخش کننده موزیک زمان اضافه کنم؟

 package com.manoochehr.nassiri.farsi_quran_test1;

import android.app.Activity;
import android.content.Intent;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.os.Handler;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.View.OnTouchListener;
import android.widget.Button;
import android.widget.SeekBar;
import android.widget.TextView;


public class Mp3player extends Activity {

    private Button        buttonPlayStop;
    private MediaPlayer   mediaPlayer;
    private SeekBar       seekBar;
    private final Handler handler = new Handler();
    private int           counter = 2;


    @Override
    public void onCreate(Bundle icicle) {
        super.onCreate(icicle);
        setContentView(R.layout.player);
        initViews();
    }


    private void initViews() {
        buttonPlayStop = (Button) findViewById(R.id.ButtonPlayStop);
        buttonPlayStop.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                buttonClick();
            }
        });

        mediaPlayer = MediaPlayer.create(this, R.raw.joze1);
        seekBar = (SeekBar) findViewById(R.id.SeekBar01);
        seekBar.setMax(mediaPlayer.getDuration());
        seekBar.setOnTouchListener(new OnTouchListener() {

            @Override
            public boolean onTouch(View v, MotionEvent event) {
                seekChange(v);
                return false;
            }
        });
    }


    public void startPlayProgressUpdater() {
        seekBar.setProgress(mediaPlayer.getCurrentPosition());
        if (mediaPlayer.isPlaying()) {
            Runnable notification = new Runnable() {

                @Override
                public void run() {
                    startPlayProgressUpdater();
                }
            };
            handler.postDelayed(notification, 1000);
        } else {
            mediaPlayer.pause();
            buttonPlayStop.setText(getString(R.string.play_str));
            seekBar.setProgress(0);
        }
    }


    private void seekChange(View v) {
        if (mediaPlayer.isPlaying()) {
            SeekBar sb = (SeekBar) v;
            mediaPlayer.seekTo(sb.getProgress());
        }
    }


    private void buttonClick() {
        if (buttonPlayStop.getText() == getString(R.string.play_str)) {
            buttonPlayStop.setText(getString(R.string.pause_str));
            TextView header = (TextView) findViewById(R.id.header);
            header.setText("در حال پخش...");

            try {
                mediaPlayer.start();
                startPlayProgressUpdater();
            }
            catch (IllegalStateException e) {
                mediaPlayer.pause();
            }
        } else {
            buttonPlayStop.setText(getString(R.string.play_str));
            TextView header = (TextView) findViewById(R.id.header);
            header.setText("مکث شده!");
            mediaPlayer.pause();
        }

        Button gotojoze2 = (Button) findViewById(R.id.backfromplayer);
        final Intent intent2 = new Intent(Mp3player.this, MenuActivity.class);
        gotojoze2.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View arg0) {
                // Mp3player.this.startActivity(intent2);
                finish();
                System.exit(0);
            }
        });
    }


    @Override
    public void onBackPressed() {
        finish();
        System.exit(0);
        final Intent intent3 = new Intent(Mp3player.this, MenuActivity.class);
        Mp3player.this.startActivity(intent3);
        super.onBackPressed();

    }
}