Platform.Uno, .Net 7.0 and IOS - Token received but not push notifications

[MCAleckson]

My Platform.UNO Android app using this plugin for Firebase both receives a Firebase token and successfully receives push notifications.

However, in IOS, I only get the Firebase token as displayed during the firing of the TokenChanged event. The NotificationReceived event never fires when I send a notification through Firebase via Postman.

One thing's for sure - I'm clearly confused on registering the IOS/Platform.Uno app for notifications as the "UNUserNotificationCenter.Current.Delegate" shows in this IOS code to initialize Firebase and set the event handlers.

Thanks in advance for any help you can give.

---

   private void InitializeIOSFirebase()
   {
       try
       {
           if (UIDevice.CurrentDevice.CheckSystemVersion(10, 0))                   // For iOS 10 display notification (sent via APNS)
           {
              // UNUserNotificationCenter.Current.Delegate = this;     // THIS FAILS TO COMPILE

               var authOptions = UNAuthorizationOptions.Alert | UNAuthorizationOptions.Badge | UNAuthorizationOptions.Sound;
               UNUserNotificationCenter.Current.RequestAuthorization(authOptions, (granted, error) => {
                   Console.WriteLine(granted);
               });
           }
           else
           {
               // iOS 9 or before
               var allNotificationTypes = UIUserNotificationType.Alert | UIUserNotificationType.Badge | UIUserNotificationType.Sound;
               var settings = UIUserNotificationSettings.GetSettingsForTypes(allNotificationTypes, null);
               UIApplication.SharedApplication.RegisterUserNotificationSettings(settings);
           }

           UIApplication.SharedApplication.RegisterForRemoteNotifications();

           CrossFirebase.Initialize();
           FirebaseCloudMessagingImplementation.Initialize();
           CrossFirebaseCloudMessaging.Current.CheckIfValidAsync();
           CrossFirebaseCloudMessaging.Current.SubscribeToTopicAsync("General");
           CrossFirebaseCloudMessaging.Current.SubscribeToTopicAsync("/topics/all");

           CrossFirebaseCloudMessaging.Current.TokenChanged += (s, p) =>
           {
               System.Diagnostics.Debug.WriteLine($"TOKEN RECIEVED EVENT: {p.Token}");
           };

           CrossFirebaseCloudMessaging.Current.Error += (s, p) =>
           {
               try
               {
                   System.Diagnostics.Debug.WriteLine($"PUSH NOTIFICATION ERROR EVENT: {p.Message}");

               }
               catch (Exception ex)
               {
                   Console.WriteLine(ex.Message);
               }
           };

           CrossFirebaseCloudMessaging.Current.NotificationReceived += (s, p) =>
           {
               try
               {
                   System.Diagnostics.Debug.WriteLine("PUSH NOTIFICATION RECEIVED EVENT: ");
               }
               catch (Exception ex)
               {
                   Console.WriteLine(ex.Message);
               }
           };
       }

       catch (Exception ex) 
       {
           Console.WriteLine(ex.Message);
       }

---

[MCAleckson]

I found my problem.

In his Legacy documentation (which applies to my case since though I'm using .Net7 I'm not using MAUI) Tobias says:

"Take a look at the documentation for the Xamarin.Firebase.iOS.CloudMessaging packages, because Plugin.Firebase's code is abstracted but still very similar."

Indeed.

I was not properly using Messaging.SharedInstance... as those documents depict.

For instance,

    public override void ReceivedRemoteNotification(UIApplication application, NSDictionary userInfo)
    {
        // If you are receiving a notification message while your app is in the background,
        // this callback will not be fired till the user taps on the notification launching the application.
        // TODO: Handle data of notification

        // With swizzling disabled you must let Messaging know about the message, for Analytics
        Messaging.SharedInstance.AppDidReceiveMessage (userInfo);

        // Print full message.
        Console.WriteLine(userInfo);
    }

So I'll echo here - if you're trying to use Tobias' plugins with Xamarin or Platform.Uno or something other than Maui - pay close attention to the documentation in the Legacy branch and to the other documents linked there.

Thanks!