当一些数据被推送到我的数据库时，我如何从javascript向主题发送通知负载数据

Question

每当一些数据被推送到我的实时数据库时，我都会尝试向我的android推送通知。

• Myandroid代码(读取通知数据(：

  public class MyFirebaseMessagingService extends FirebaseMessagingService {
  @Override
  public void onMessageReceived(@NonNull RemoteMessage remoteMessage) {
  FirebaseMessaging.getInstance().subscribeToTopic("electricity bill").addOnSuccessListener(new OnSuccessListener<Void>() {
  @Override
  public void onSuccess(Void aVoid) {
  String notificationTitle = null, notificationBody = null;
  // Check if message contains a notification payload
  if (remoteMessage.getNotification() != null) {
  notificationTitle = remoteMessage.getNotification().getTitle();
  notificationBody = remoteMessage.getNotification().getBody();
  }
  if(Objects.requireNonNull(notificationBody).contains(pf.getText().toString()))
  sendLocalNotification(notificationTitle, notificationBody);
  }
  });
  }
  private void sendLocalNotification(String notificationTitle, String notificationBody) {
  Intent intent = new Intent(this, record_viewer.class);
  intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
  PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, intent,
  PendingIntent.FLAG_ONE_SHOT);
  Uri defaultSoundUri= RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
  NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(this)
  .setAutoCancel(true)   //Automatically delete the notification
  .setSmallIcon(R.mipmap.ic_launcher) //Notification icon
  .setContentIntent(pendingIntent)
  .setContentTitle(notificationTitle)
  .setContentText(notificationBody)
  .setSound(defaultSoundUri);
  NotificationManager notificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
  notificationManager.notify(1234, notificationBuilder.build());
  }
  }
  

• 我的web代码(这会发送通知数据(：

  在我的HTML页面中，我包含了以下库：

  <script src="https://www.gstatic.com/firebasejs/9.10.0/firebase-app-compat.js"></script>
  <script src="https://www.gstatic.com/firebasejs/9.10.0/firebase-database-compat.js"></script>
  

  和我的javascript:

  const firebaseConfig = {
  apiKey: "AIzW&HFSIHF&WUFSJKFVSIUBbsfhs98fhsifj",
  authDomain: "some domain here",
  projectId: "project id",
  storageBucket: "storage bucket",
  messagingSenderId: "123a23283905",
  databaseURL: "https://some url here",
  appId: "some id here"
  };
  firebase.initializeApp(firebaseConfig);
  for(var k=1; k<table.rows.length; k++){
  if(table.rows[k].cells.item(10).innerHTML != 0){
  firebase.database().ref("ac/0/").push(
  {
  "Current Date":document.getElementsByClassName("curr_date")[k-1].value,
  "EmpNo":table.rows[k].cells.item(1).innerHTML,
  "Flag":0,
  "Prev Date":document.getElementsByClassName("prev_date")[k-1].value,
  "Total charge":table.rows[k].cells.item(10).innerHTML
  }
  )
  }
  }
  //How do I send the notification payload to the topic "electricity bill"?
  

---

我想通过有效载荷将EmpNo和Total charge数据发送到该主题，如何继续？请帮帮我。

Answer 1

您可以将云函数用于您的用例，特别是实时数据库触发器。如果您只是在侦听数据库中的数据更新，则可以使用onCreate()。您可以在这里检查其他事件处理程序，这样您就会知道什么最适合您的用例。

下面是一个关于如何使用RTDB触发器发送通知的示例代码，供您参考。发送通知时只需使用sendToTopic((，因为您的目标是某个主题。