android - FirebaseMessagingService - 如何从后台更新数据库或 SharedPreferences？

Question

我正在尝试在收到来自 Firebase 控制台的推送通知后更新应用程序数据库。它在应用程序运行时有效，但是当应用程序在后台或进程被终止时，我无法更改 SharedPreferences 中的数据。

但是使用 NotificationManager 发送通知是有效的。从 Firebase 检索推送通知时，有什么方法可以更新数据库吗？

 private void sendNotification(String messageBody) {
    Intent intent = new Intent(this, EventListActivityDrawerNewMenu.class);
    intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
    PendingIntent pendingIntent = PendingIntent.getActivity(this, 0 /* Request code */, intent,
            PendingIntent.FLAG_ONE_SHOT);

    Uri defaultSoundUri= RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
    NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(this)
            .setSmallIcon(R.drawable.ic_launcher)
            .setContentTitle("FCM Message")
            .setContentText(messageBody)
            .setAutoCancel(true)
            .setSound(defaultSoundUri)
            .setContentIntent(pendingIntent);

    NotificationManager notificationManager =
            (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);

    notificationManager.notify(0 /* ID of notification */, notificationBuilder.build());
}

private void saveDataToPreferences(String data) {
    Context context = this;
    SharedPreferences sharedPreferences = getApplicationContext().getSharedPreferences(UpdateDataService.MY_PREFS_NAME, MODE_PRIVATE);
    SharedPreferences.Editor editor = sharedPreferences.edit();
    editor.putString(UpdateDataService.MY_PREFS_NAME, data);
    editor.commit();
}

@Override
public void onMessageReceived(RemoteMessage remoteMessage) {
    android.os.Debug.waitForDebugger();

    Log.d(TAG, "From: " + remoteMessage.getFrom());

    if (remoteMessage.getData().size() > 0) {
        Log.d(TAG, "Message data payload: " + remoteMessage.getData());
    }

    if (remoteMessage.getNotification() != null) {
        Log.d(TAG, "Message Notification Body: " + remoteMessage.getNotification().getBody());
        sendNotification(remoteMessage.getNotification().getBody());
    }

    saveDataToPreferences(remoteMessage.getNotification().getBody());

}

Answer 1

好的，我已经解决了这个问题。 Firebase 有两种类型的推送通知:显示消息和数据消息。并且只有数据消息才能唤醒您的服务以更新数据库。您不能从 firebase 控制台创建数据消息，您只能通过 url 上的 post 请求发送它:

https://fcm.googleapis.com/fcm/send

正文:

{
"data": {
    "data" : "some message",
    "other_key" : true
 },
"registration_ids": ["here your user token", "another user token"]}

标题:

• 键:内容类型，值:application/json

• 键:授权，值:key=your-server-key