播放默认铃声

Uri alert = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_ALARM);  mMediaPlayer = new MediaPlayer();  mMediaPlayer.setDataSource(this, alert);  final AudioManager audioManager = (AudioManager)getSystemService(Context.AUDIO_SERVICE);  if (audioManager.getStreamVolume(AudioManager.STREAM_ALARM) != 0) {             player.setAudioStreamType(AudioManager.STREAM_ALARM);             player.setLooping(true);             player.prepare();             player.start();   }

会出现 Couldn't open fd for content://settings/system/ringtone

但是在真机上是可以的