Enable Media Volume Slider in Android application

Some Android programs trigger the "media volume" slider when the hardware volume up/down buttons are pressed. My application seems to set the ringer volume when the hardware buttons are pressed.

How would I enable the media 开发者_StackOverflow社区volume slider?

I would hate for users to have to go into their settings to change the media volume when they use my application.

Just call Activity.setVolumeControlStream(AudioManager.STREAM_MUSIC) in your Activity's onCreate method.

private AudioManager audio;

Inside onCreate:

audio = (AudioManager) getSystemService(Context.AUDIO_SERVICE);

Override onKeyDown:

@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
    switch (keyCode) {
    case KeyEvent.KEYCODE_VOLUME_UP:
        audio.adjustStreamVolume(AudioManager.STREAM_MUSIC,
                AudioManager.ADJUST_RAISE, AudioManager.FLAG_SHOW_UI);
        return true;
    case KeyEvent.KEYCODE_VOLUME_DOWN:
        audio.adjustStreamVolume(AudioManager.STREAM_MUSIC,
                AudioManager.ADJUST_LOWER, AudioManager.FLAG_SHOW_UI);
        return true;
    default:
        return false;
    }
}