SeekBar and media player in android

I've used this tutorial with success, it's really simple to understand: www.androidhive.info/2012/03/android-building-audio-player-tutorial/

This is the interesting part:

/**
 * Update timer on seekbar
 * */
public void updateProgressBar() {
    mHandler.postDelayed(mUpdateTimeTask, 100);
}  

/**
 * Background Runnable thread
 * */
private Runnable mUpdateTimeTask = new Runnable() {
       public void run() {
           long totalDuration = mp.getDuration();
           long currentDuration = mp.getCurrentPosition();

           // Displaying Total Duration time
           songTotalDurationLabel.setText(""+utils.milliSecondsToTimer(totalDuration));
           // Displaying time completed playing
           songCurrentDurationLabel.setText(""+utils.milliSecondsToTimer(currentDuration));

           // Updating progress bar
           int progress = (int)(utils.getProgressPercentage(currentDuration, totalDuration));
           //Log.d("Progress", ""+progress);
           songProgressBar.setProgress(progress);

           // Running this thread after 100 milliseconds
           mHandler.postDelayed(this, 100);
       }
    };

/**
 *
 * */
@Override
public void onProgressChanged(SeekBar seekBar, int progress, boolean fromTouch) {

}

/**
 * When user starts moving the progress handler
 * */
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
    // remove message Handler from updating progress bar
    mHandler.removeCallbacks(mUpdateTimeTask);
}

/**
 * When user stops moving the progress hanlder
 * */
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
    mHandler.removeCallbacks(mUpdateTimeTask);
    int totalDuration = mp.getDuration();
    int currentPosition = utils.progressToTimer(seekBar.getProgress(), totalDuration);

    // forward or backward to certain seconds
    mp.seekTo(currentPosition);

    // update timer progress again
    updateProgressBar();
}

To create a 'connection' between SeekBar and MediaPlayer you need first to get your current recording max duration and set it to your seek bar.

mSeekBar.setMax(mFileDuration/1000); // where mFileDuration is mMediaPlayer.getDuration();

After you initialise your MediaPlayer and for example press play button, you should create handler and post runnable so you can update your SeekBar (in the UI thread itself) with the current position of your MediaPlayer like this :

private Handler mHandler = new Handler();
//Make sure you update Seekbar on UI thread
MainActivity.this.runOnUiThread(new Runnable() {

    @Override
    public void run() {
        if(mMediaPlayer != null){
            int mCurrentPosition = mMediaPlayer.getCurrentPosition() / 1000;
            mSeekBar.setProgress(mCurrentPosition);
        }
        mHandler.postDelayed(this, 1000);
    }
});

and update that value every second.

If you need to update the MediaPlayer's position while user drag your SeekBar you should add OnSeekBarChangeListener to your SeekBar and do it there :

        mSeekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {

        @Override
        public void onStopTrackingTouch(SeekBar seekBar) {

        }

        @Override
        public void onStartTrackingTouch(SeekBar seekBar) {

        }

            @Override
            public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {                
                if(mMediaPlayer != null && fromUser){
                    mMediaPlayer.seekTo(progress * 1000);
                }
            }
    });

And that should do the trick! : )

EDIT: One thing which I've noticed in your code, don't do :

public MainActivity() {
    mFileName = Environment.getExternalStorageDirectory().getAbsolutePath();
    mFileName += "/audiorecordtest.3gp";
}

make all initialisations in your onCreate(); , do not create constructors of your Activity.

Code in Kotlin:

var updateSongTime = object : Runnable {
            override fun run() {
                val getCurrent = mediaPlayer?.currentPosition
                startTimeText?.setText(String.format("%d:%d",
                        TimeUnit.MILLISECONDS.toMinutes(getCurrent?.toLong() as Long),
                        TimeUnit.MILLISECONDS.toSeconds(getCurrent?.toLong()) -
                                TimeUnit.MINUTES.toSeconds(
                                        TimeUnit.MILLISECONDS.toMinutes(getCurrent?.toLong()))))
                seekBar?.setProgress(getCurrent?.toInt() as Int)
                Handler().postDelayed(this, 1000)
            }
        }

For changing media player audio file every second

If user drags the seek bar then following code snippet can be use

Statified.seekBar?.setOnSeekBarChangeListener(object : SeekBar.OnSeekBarChangeListener {
            override fun onProgressChanged(seekBar: SeekBar, i: Int, b: Boolean) {
                if(b && Statified.mediaPlayer != null){
                    Statified.mediaPlayer?.seekTo(i)
                }

            }
            override fun onStartTrackingTouch(seekBar: SeekBar) {}
            override fun onStopTrackingTouch(seekBar: SeekBar) {}
        })

After you initialize your MediaPlayer and SeekBar, you can do this :

 Timer timer = new Timer();
    timer.scheduleAtFixedRate(new TimerTask() {
        @Override
        public void run() {
            mSeekBar.setProgress(mMediaPlayer.getCurrentPosition());
        }
    },0,1000);

This updates SeekBar every second(1000ms)

And for updating MediaPlayer, if user drag SeekBar, you must add OnSeekBarChangeListener to your SeekBar :

mSeekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
        @Override
        public void onProgressChanged(SeekBar seekBar, int i, boolean b) {
            mMediaPlayer.seekTo(i);
        }

        @Override
        public void onStartTrackingTouch(SeekBar seekBar) {

        }

        @Override
        public void onStopTrackingTouch(SeekBar seekBar) {

        }
    });

HAPPY CODING!!!