Android : how do you stop the running song and play the newly selected song using mediaplayer in android?

I have tried all the posts I could find and I haven't gotten any solution. This is the code I have so far:

public void onItemClick(AdapterView<?> parent, View view, int position, long id) {                
    mPlayer = new MediaPlayer();
    boolean isPlaying = false;

    String songid = ((TextView) view).getText().toString();
    Uri u = Uri.withAppendedPath(MediaStore.Audio.Media.EXTERNAL_CONTENT_URI, songid);

    try {
        mPlayer.setDataSource(getApplicationContext(), u);
    } catch (IOException e) {
        e.printStackTrace();
    }

    if (!isPlaying) {
        try {
            mPlayer.prepare();
        } catch (IOException e) {
            e.printStackTrace();
        }
        mPlayer.start();
        isPlaying = true;
    } else {
        isPlaying = false;
        mPlayer.stop();
        mPlayer.reset();

        mPlayer.start();
        isPlaying = true;
    }
}