Android开发片段设置系统声音

public static void setMaxVolumn(Context context){AudioManager audioManager = (AudioManager)context.getSystemService(Context.AUDIO_SERVICE);    //audioManager.setStreamVolume(AudioManager.STREAM_SYSTEM , 12, 0);audioManager.setRingerMode(AudioManager.RINGER_MODE_NORMAL);    Log.d("MUSIC", "max : " + 15 + " current : " + 15); }public static void setHalfVolumn(Context context){AudioManager audioManager = (AudioManager)context.getSystemService(Context.AUDIO_SERVICE);audioManager.setStreamVolume(AudioManager.STREAM_SYSTEM , 7, 0);    Log.d("MUSIC", "max : " + 15 + " current : " + 7); }public static void setSilentVolumn(Context context){AudioManager audioManager = (AudioManager)context.getSystemService(Context.AUDIO_SERVICE);//audioManager.setStreamVolume(AudioManager.STREAM_SYSTEM , 2, 0);audioManager.setRingerMode(AudioManager.RINGER_MODE_SILENT);    Log.d("MUSIC", "max : " + 15 + " current : " + 0); }