通知 Notification

 //创建一个notification
        Notification.Builder builder = new Notification.Builder(this);
        //通知第一次收到的时候在状态栏里显示的消息
        builder.setTicker("你好吗?");
        //点击就会消失
        builder.setAutoCancel(true);
        //通知栏显示的大标题
        builder.setContentTitle("通知");
        //通知栏显示的小的文本内容
        builder.setContentText("你吃了吗");
        //通知栏显示的小图标
        builder.setSmallIcon(R.drawable.ic_launcher_background);
        //点击不会消失 一般用于音乐播放器，下载栏
//        builder.setOngoing(true);
        //点击跳转
        Intent intent = new Intent(getApplicationContext(),MainActivity.class);
        PendingIntent pendingIntent = PendingIntent.getActivity(getApplicationContext(),1,intent,PendingIntent.FLAG_UPDATE_CURRENT);
        builder.setContentIntent(pendingIntent);
        Notification notification = builder.build();
        NotificationManager manager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
        manager.notify(1, notification);