How to play, pause and stop the song in android?
<p>I am making an app for Android and I have made three buttons to play, pause and stop.</p>

<p>My play and pause buttons are set up, so when I click the play button, it will become invisible and the pause button will display, and vice versa.</p>

<p>It works just fine when I click the play button, but after I click on the pause button, it gives me an error.</p>

<p>The code is given below.</p>

<pre><code> package com.mpIlango;

 import java.io.IOException;
 import java.util.ArrayList;
 import android.app.Activity;
 import android.media.MediaPlayer;
 import android.os.Bundle;
 import android.view.View;
 import android.widget.Button;
 import android.widget.RadioGroup;
 import android.widget.RadioGroup.OnCheckedChangeListener;

public class MpIlangoActivity extends Activity implements OnCheckedChangeListener {
/** Called when the activity is first created. */


MediaPlayer song1,song2,song3;
int whatsong = 0;

private ArrayList&lt;Integer&gt; songIds;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    RadioGroup rgMusic = (RadioGroup) findViewById(R.id.rgMusic);

    songIds = new ArrayList&lt;Integer&gt;();

    songIds.add(R.raw.fluet);
    songIds.add(R.raw.airtel);
    songIds.add(R.raw.titanic);


    final Button bPlay = (Button) findViewById(R.id.bPlay);
    final Button bStop = (Button) findViewById(R.id.bStop);
    final Button bPause = (Button) findViewById(R.id.bPause);

    bPause.setVisibility(View.GONE);

    rgMusic.setOnCheckedChangeListener(this);

    bPlay.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {           

             if(song1!=null)   {
                   song1.release();
                }

              if(song2!=null)  {
                   song2.release();
                }

              if(song3!=null)  {
                   song3.release();
                }

              switch (whatsong) {

                case 1:

                    try {
                        song1 = MediaPlayer.create(MpIlangoActivity.this, songIds.get(0));
                        song1.prepare();
                    } catch (IllegalStateException e) {                 
                        e.printStackTrace();
                    } catch (IOException e) {                   
                        e.printStackTrace();
                    }
                    song1.start();
                    bPlay.setVisibility(View.GONE);
                    bPause.setVisibility(View.VISIBLE);
                    break;  

                case 2:
                    try {
                        song2 = MediaPlayer.create(MpIlangoActivity.this, songIds.get(1));
                        song2.prepare();
                    } catch (IllegalStateException e) {                 
                        e.printStackTrace();
                    } catch (IOException e) {                   
                        e.printStackTrace();
                    }
                    song2.start();
                    bPlay.setVisibility(View.GONE);
                    bPause.setVisibility(View.VISIBLE);
                    break;

                case 3:
                    try {
                        song3 = MediaPlayer.create(MpIlangoActivity.this, songIds.get(2));
                        song3.prepare();
                    } catch (IllegalStateException e) {                     
                        e.printStackTrace();
                    } catch (IOException e) {               
                        e.printStackTrace();
                    }
                    song3.start();
                    bPlay.setVisibility(View.GONE);
                    bPause.setVisibility(View.VISIBLE);
                    break;
                }
            }               
    });

    bPause.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {

            bPlay.setVisibility(View.VISIBLE);
            bPause.setVisibility(View.GONE);

            if(song1.isPlaying()){
                song1.pause();          
            }

            if(song2.isPlaying()){
                song2.pause();
            }

            if(song3.isPlaying()){
                song3.pause();
            }               
        }
    });

    bStop.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {

             if(song1!=null){
                   song1.release();
               }

              if(song2!=null){
                   song2.release();
               }

              if(song3!=null){
                   song3.release();
               }                
        }
    });;        
}

@Override
public void onCheckedChanged(RadioGroup group, int rbId) {

    switch (rbId) {

    case R.id.rbMusic1:
        whatsong = 1;           
        break;
    case R.id.rbMusic2:
        whatsong = 2;           
        break;
    case R.id.rbMusic3:
        whatsong = 3;           
        break;

    }       

}
</code></pre>

<p>}</p>
