Android uses notifications (Notification)

Notification is a feature in the Android system. Let's take a look at how Notification is used.
First, a NotificationManager is needed to manage notifications, which can be obtained through the getSystemService() method of Context. Here you need to pass in Context.NOTIFICATION_SERVICE to get NotificationManager. Next, you need to create a Notification object, which is used to store various information about the notification. The previous version of Andorid was constructed directly, that is, Notification notification = new Notification(); Now this is generally not done, and the Notification.Builder object is used to create the Notification.
First look at the usage of basic notification

public class NotificationActivity extends AppCompatActivity {
    Button btn_notification;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_notification);
        btn_notification = (Button) findViewById(R.id.btn_notification);
        final NotificationManager notificationManager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);

        Notification.Builder builder = new Notification.Builder(this);
        builder.setContentTitle("我的通知")//设置标题
                .setContentText("通知消息")//设置消息内容
                .setContentIntent(getDefault(Notification.FLAG_AUTO_CANCEL))//这是必须的东西，用来设置点击事件
                .setTicker("有新的消息来了")//设置通知来了时候的提示
                .setOngoing(false)
                .setWhen(System.currentTimeMillis())//设置通知的时间
                .setPriority(Notification.PRIORITY_DEFAULT)
                .setDefaults(Notification.DEFAULT_ALL)//设置条件
                .setSmallIcon(R.drawable.zhenji);//设置通知的图标
        final Notification mNotification = builder.build();
        //创建notification
        btn_notification.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                notificationManager.notify(1,mNotification);
            }
        });

    }

    public PendingIntent getDefault(int flag) {
        PendingIntent pendingIntent = PendingIntent.getActivity(this, 1, new Intent(), flag);
        return pendingIntent;
    }
}

The difference between Intent and pendingIntent
pendingIntent can be used to start an activity, start a service or send a broadcast. This is very similar to an Intent. A pendingIntent can be understood as a delayed-execution Intent. The way to get a PendingIntent is very simple, you can choose getActivity() or getService() or getBroadcast()

Summary: The basic usage of notification is very simple. If you want to add click events or carry parameters, you can do it in the third parameter Intent of PendingIntent.