public void onRadioClick(View v) {

    if (!isPLAYING) {
        isPLAYING = true;
        MediaPlayer mp = new MediaPlayer();
        try {
            mp.setDataSource(getString(R.string.audio_stream));
            mp.prepare();
            mp.start();
        } catch (IOException e) {
            Log.e(LOG_TAG, "prepare() failed");
        }
    } else {
        isPLAYING = false;
        stopPlaying();
    }
}

private void stopPlaying() {
    mp.release();
    mp = null;
}

Look at these two tutorials, In these the .mp3 files are playing through web url,

Example of streaming mp3 mediafile from URL with Android MediaPlayer class

Play Mp3 file from a Url

Also if you want to play .mp3 file in background I think you have to use Service and AIDL for it,

Look at basic Android-Music Player demo MusicDroid - Audio Player Part II it describe how to use Service and AIDl for your Audio Player.

Thanks..

It looks good to me. Sensible identifiers, usual idioms.

After defining myHandler, delete the 2nd ; semicolon.

You probably want a boolean for oneTimeOnly.

Your "Pausing sound" toast is nice enough, but consider defining a TextView where you can flash messages, as that can give you greater thread scheduling control. A toast can block other threads from running for a moment, which will sometimes be important to an app.

If intent.getExtras() is null, it seems the caller did the Wrong Thing, so you might want to give up and signal fatal error at that point.

simple Media Player with streaming example.For xml part you need one button with id button1 and two images in your drawable folder with name button_pause and button_play and please don't forget to add the internet permission in your manifest.

public class MainActivity extends Activity {
private Button btn;
/**
 * help to toggle between play and pause.
 */
private boolean playPause;
private MediaPlayer mediaPlayer;
/**
 * remain false till media is not completed, inside OnCompletionListener make it true.
 */
private boolean intialStage = true;


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    btn = (Button) findViewById(R.id.button1);
    mediaPlayer = new MediaPlayer();
    mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
    btn.setOnClickListener(pausePlay);

}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.activity_main, menu);
    return true;
}

private OnClickListener pausePlay = new OnClickListener() {

    @Override
    public void onClick(View v) {
        // TODO Auto-generated method stub
        // TODO Auto-generated method stub

        if (!playPause) {
            btn.setBackgroundResource(R.drawable.button_pause);
            if (intialStage)
                new Player()
                        .execute("http://www.virginmegastore.me/Library/Music/CD_001214/Tracks/Track1.mp3");
            else {
                if (!mediaPlayer.isPlaying())
                    mediaPlayer.start();
            }
            playPause = true;
        } else {
            btn.setBackgroundResource(R.drawable.button_play);
            if (mediaPlayer.isPlaying())
                mediaPlayer.pause();
            playPause = false;
        }
    }
};
/**
 * preparing mediaplayer will take sometime to buffer the content so prepare it inside the background thread and starting it on UI thread.
 * @author piyush
 *
 */

class Player extends AsyncTask<String, Void, Boolean> {
    private ProgressDialog progress;

    @Override
    protected Boolean doInBackground(String... params) {
        // TODO Auto-generated method stub
        Boolean prepared;
        try {

            mediaPlayer.setDataSource(params[0]);

            mediaPlayer.setOnCompletionListener(new OnCompletionListener() {

                @Override
                public void onCompletion(MediaPlayer mp) {
                    // TODO Auto-generated method stub
                    intialStage = true;
                    playPause=false;
                    btn.setBackgroundResource(R.drawable.button_play);
                    mediaPlayer.stop();
                    mediaPlayer.reset();
                }
            });
            mediaPlayer.prepare();
            prepared = true;
        } catch (IllegalArgumentException e) {
            // TODO Auto-generated catch block
            Log.d("IllegarArgument", e.getMessage());
            prepared = false;
            e.printStackTrace();
        } catch (SecurityException e) {
            // TODO Auto-generated catch block
            prepared = false;
            e.printStackTrace();
        } catch (IllegalStateException e) {
            // TODO Auto-generated catch block
            prepared = false;
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            prepared = false;
            e.printStackTrace();
        }
        return prepared;
    }

    @Override
    protected void onPostExecute(Boolean result) {
        // TODO Auto-generated method stub
        super.onPostExecute(result);
        if (progress.isShowing()) {
            progress.cancel();
        }
        Log.d("Prepared", "//" + result);
        mediaPlayer.start();

        intialStage = false;
    }

    public Player() {
        progress = new ProgressDialog(MainActivity.this);
    }

    @Override
    protected void onPreExecute() {
        // TODO Auto-generated method stub
        super.onPreExecute();
        this.progress.setMessage("Buffering...");
        this.progress.show();

    }
}

@Override
protected void onPause() {
    // TODO Auto-generated method stub
    super.onPause();
    if (mediaPlayer != null) {
        mediaPlayer.reset();
        mediaPlayer.release();
        mediaPlayer = null;
    }
}

You can play a URL in just_audio like this:

final player = AudioPlayer();
await player.setUrl('https://example.com/song.mp3');
player.play();
player.pause();
player.seek(Duration(seconds: 143);

To add notification support, the easiest way is to add just_audio_background. You need to change the above code slightly so that instead of calling setUrl, you now do this:

await player.setAudioSource(AudioSource.uri(
  'https://example.com/song.mp3',
  tag: MediaItem(
    id: 'Some unique ID',
    title: 'Song title',
    album: 'Song album',
    artUri: Uri.parse('https://example.com/art.jpg'),
  ),
));

Now once that song starts playing, the supplied metadata will also be shown in the notification.

just_audio_background must also be initialised in your main:

Future<void> main() async {
  await JustAudioBackground.init(/* See API for options */);
  runApp(MyApp());
}

And don't forget to follow the platform-specific setup instructions for each plugin:

• just_audio
• just_audio_background

Note that just_audio_background uses the audio_service plugin under the hood, so if your app has more complex requirements, you could use that plugin directly.

If you have questions about how to build the actual UI, you can create a separate question on that, or you can look at the above two links because each plugin includes an example app which demonstrates how to link it all up in a UI.