红米手机2 使用Notification中的LED属性，LED灯不亮，求大神解答

我的MainActivity中的代码如下：

 public void onClick(View v) {
        switch (v.getId()) {
        case R.id.send_notice:
            NotificationManager manager=(NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
            Notification notification=new Notification(R.drawable.ic_launcher, "This is ticker text", System.currentTimeMillis());
            notification.ledARGB=Color.RED;
            notification.ledOnMS=300;
            notification.ledOffMS=1000;
            notification.flags |=Notification.FLAG_SHOW_LIGHTS;
            Intent sendIntent =new Intent(MainActivity.this,NotificationActivity.class);
            PendingIntent pendingIntent=PendingIntent.getActivity(MainActivity.this, 0, sendIntent, PendingIntent.FLAG_CANCEL_CURRENT);
            //将第四个参数使用PendingIntent
            notification.setLatestEventInfo(MainActivity.this, "This is Content title", "This is Content text", pendingIntent);
            manager.notify(1, notification);
            break;
        default:
            break;
        }
    }