MediaPlayer works in Android, but progress does not

Question

I've been working on this for a while, trying to get this tutorial to work ( http://united-coders.com/nico-heid/an-android-seekbar-for-your-mediaplayer/ ), but I haven't had any luck. The audio playback works perfect, but the SeekBar doesn't move.

package com.example.playingaudio;

import java.io.FileInputStream;

import android.app.Activity;
import android.media.AudioManager;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.view.View;
import android.widget.SeekBar;

public class MainActivity extends Activity implements Runnable {

    private MediaPlayer mediaPlayer;
    private SeekBar progress;

    @Override
    protected void onCreate(Bundle savedInstanceState) {

        setContentView(R.layout.activity_main);
        super.onCreate(savedInstanceState);
        progress = (SeekBar) findViewById(R.id.seekBar1);

    }

    public void playButton(View view) {
        try {
            playRecording();

        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

    protected void playRecording() throws Exception {
        final MediaPlayer mediaPlayer = new MediaPlayer();
        FileInputStream fileStream = new FileInputStream(
                "/sdcard/Download/mySong.mp3");
        mediaPlayer.setDataSource(fileStream.getFD());
        mediaPlayer.prepare(); // might take long! (for buffering, etc)
        mediaPlayer.start();
        run();
    }

    private void ditchMediaPlayer() {
        if (mediaPlayer != null) {
            try {
                mediaPlayer.release();

            } catch (Exception e) {
                e.printStackTrace();
            }
        }

    }

    @Override
    public void run() {
        // mp is your MediaPlayer
        // progress is your ProgressBar

        int currentPosition = 0;
        int total = mediaPlayer.getDuration();
        progress.setMax(total);
        while (mediaPlayer != null && currentPosition < total) {
            try {
                Thread.sleep(1000);
                currentPosition = mediaPlayer.getCurrentPosition();
            } catch (InterruptedException e) {
                return;
            } catch (Exception e) {
                return;
            }
            progress.setProgress(currentPosition);
        }
    }

}

Answer 1

Try changing this line

final MediaPlayer mediaPlayer = new MediaPlayer();

To, this line

mediaPlayer = new MediaPlayer();

The reason is you already have a class variable mediaPlayer declared and why are you declaring the local variable again with the same name.

Answer 2

The reason your bar is not updating is because you aren't giving it a chance to. You have a constant loop on your UI thread that consists mostly of sleep() . You can't do that and expect the UI to update.

If you look at that tutorial more closely, you'll see that they don't call runOnUiThread() . In fact, at the bottom there is a link back to SO , which shows a bit more of the code involved. There's just a new Thread created, and start() is run. Nothing too tricky.

---

Example:

(call this method after mediaPlayer.start() ):

private void createProgressThread() {   
    progressUpdater = new Runnable() {
        @Override
        public void run() {
            //...
            //...
        }
    };
    Thread thread = new Thread(progressUpdater);
    thread.start();
}