怎么拦截android手机下声音控制

如何拦截android手机上声音控制
一般android手机旁边有两个控制声音加、减的按钮,我现在的项目要求用户按了声音的加、减后拦截下来,把这两个命令用于别的用途,求大神解答~

------解决方案--------------------
好像是这个,错了别喷我
Java code
@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_PLAY_SOUND | AudioManager.FLAG_SHOW_UI); 
        return true; 
    case KeyEvent.KEYCODE_VOLUME_DOWN: 
        audio.adjustStreamVolume( 
            AudioManager.STREAM_MUSIC, 
            AudioManager.ADJUST_LOWER, 
            AudioManager.FLAG_PLAY_SOUND | AudioManager.FLAG_SHOW_UI); 
        return true; 
    default: 
        break; 
    } 
    return super.onKeyDown(keyCode, event); 
}