Push Notifications not always working on iPhone - ios

I face the following weird problem. I have a setup for notifications using Azure NotificationHub and Xamarin to develop an iOS app. It works fine with the following exception. Some times some notifications sent from my backend server (C# Visual Studio Windows Form Application) cause the iPhone to flash, I hear the notification sound, no notification is shown and older notifications of my app are removed from the list. Any idea what might be causing this?
Thanks

I see that you write:
I hear the notification sound, no notification is shown and older notifications of my app are removed from the list.
If you hear the notification sound, that means that the neither the APNS nor the Azure Notification Hub is the problem, because you are actually receiving the notification on the device.
No notification is shown.
1.This means that either the implementation of your code is deciding to actually receive the notification and do nothing with it. Check t Receiving Push Notifications while in background
This could also mean that in settings you disabled all the notification balloons, alerts and other properties. Make sure your app has actually the proper settings to work with notifications. (Believe me, it happens) https://support.apple.com/en-us/HT201925
Older notifications of my app are removed from the list. First of all I do not understand how do you have notifications on the list (did you actually received notifications somehow?). In any case, the notifications are removed by code when you enter your app. Please review this question (iOS application: how to clear notifications?)
Please mark my answer correct if it helped you, if not. Please provide more code of your implementation so we can provide you a better answer.
Best Regards.

Related

FCM Notifications not arriving on iOS

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Scorb wants to draw more attention to this question.
I have a cross platform flutter app. I am using FCM to send notifications and they are not arriving on the iOS app in any state (foreground, background, terminated). I am testing on a physical device.
The notifications work on Android, so I know the topic subscription and send code is correct.
I have followed these steps for configuration defined here...
https://firebase.flutter.dev/docs/messaging/apple-integration/
To verify I have:
added and initialized firebase using google-services-info.plist.
created and added my APNS key
created the app identifier in the Apple Developer center and confirmed it matches my apps bundle id (and added push notification
capability for the identifier.
added push notification capability to the app in xcode
added background fetch and background remote notification capabilities to the app in xcode.
It seems like I have addressed every step to configure FCM on iOS. But none of my notifications arrive.
When the app is minimized, no system tray notification is triggered, and when in the foreground the FirebaseMessaging.onMessage is never triggered, like is is when on Android.
An important note is that this is the second iOS app added to this project, and the first iOS app works correctly. Though there is no indication that there are any special steps for a second app.
We saw a similar problem (for a native iOS app) where FCM would deliver to one app in the project but not the other. The mistake we made was not repeating the configuration in Firebase for the other apple bundle id since each app in our project has a different bundle id. Given it works for one of your iOS apps but not the other on the same project, it sounds like you've got the same issue.
Also, a good diagnostic step is to use the Firebase Console to manually send off a Push Notification to a particular app. It means you can then discount errors further upstream in your backend that may not have caused FCM to be invoked.
Have you tried to send testing notifications via firebase console?
You can log your device token in your app.
Background notification must work if you have done correct with firebase and APN settings despite without implementing some methods of AppDelegate file for remote notification on the next step.
Your question is very blur to have a specific answer but you can separate your concerns to find the issue and then try to resolve that:
1. Make sure about the APNs configuration
First, try to send a notification to your iOS app, directly using the APNS key. If you get the notification, it means you have configured the APNS correctly
2. Make sure about the firebase setup
Check with both the Android and iOS app and see if there are connected to the firebase console. You can use the real-time event to confirm that.
3. Make sure you have implemented the correct methods.
Firebase and apple have different methods for push notifications. Make sure you are implementing the correct one. Also, it may vary based on the configuration file of firebase. search for iOS firebase swizzling for more information
4. Make sure you got the right permissions from the user
You should get the notification permission from the user before trying to show any notification. Make sure you've done that
Note that you may have already tried some of these but I've mentioned them for the sake of completeness. Hope it helps you and others.

Modify Notification data before displaying to user in iOS

I have an app in which I am using an FCM notification when there is an event from server.
I want to get the notification data and update the message from one of the parameter from Notification Payload when app is in background, foreground or killed.
I have tried to use Silent Push Notification with Content Available but when my app is killed, then I am unable to receive callback in my App delegate.
I have tried lots of links from StackOverflow but could not get the perfect suggestion.
If you find duplicate, then please provide me the link but solution with different iOS (12,13,14,15) versions.
My problem is just like this Stack Link
It sounds like what you want is a Notification Service Extension. This is a separate binary (packaged with your app) that can run when a notification is received. Your extension can intercept the push-notification payload, and modify it, so that other things can be displayed.
https://developer.apple.com/documentation/usernotifications/unnotificationserviceextension
This is also really good, too.
https://www.raywenderlich.com/8277640-push-notifications-tutorial-for-ios-rich-push-notifications

VoIP notifications in hybrid apps not working

Recently Apple changed its way of handling VoIP notifications. Now they force you to use CallKit in the same run loop in order not to throw your notification away. The trace I get is this one
Apps receving VoIP pushes must post an incoming call (via CallKit or IncomingCallNotifications) in the same run loop as pushRegistry:didReceiveIncomingPushWithPayload:forType:[withCompletionHandler:] without delay.
When you get this warning three times, the system is "dropping your notifications on the floor".
The problem here is that I'm developing a hybrid VoIP app using the phonegap-plugin-push, and I'm afraid that the on notification event is not fast enough (or at least not the same run loop) for iOS.
Did anyone face this issue?
I've thought of changing to regular push notifications, but I can't find a way to make my app relaunch when it's killed and execute some code (launch CallKit, for example).
Edit:
I'm trying this approach with push notifications and I already configured the background modes. I noticed that sending the "content-available" and some data, like "badge", or "alert" in the notification, the app is launched if it went to background recently. After 15 minutes in the background the push notification arrives but the app doesn't launch anymore
Thank you in advance.
Our app uses CallKit and push notifications, and it launches when a push notification arrives for a new incoming call. It has to be configured in the project build and run once to register with iOS for this, though.
I found a solution:
Since iOS changed its policy about handling voip push notifications, it forces you to report a new incoming call when receiving the voip: https://forums.developer.apple.com/thread/117939
This plugin does it: https://github.com/mattkhaw/cordova-plugin-callkit
It merges two plugins (WebsiteBeaver/CordovaCall and Hitman666/cordova-ios-voip-push). It worked for me. I just had to remove the receiveCall from the javascript and tweak a little bit the plugin.
The methods related to the voip notifications register are in the cordovaCall class, so it is pretty straightforward to work with.

How to change how a remote notification is presented before presentation?

How should I change how a remote notification is presented in iOS before the system presents it? In fact, silence it. There are times where my app has canceled a Firebase topic subscription locally, but that cancellation is not delivered to the server in time. So, when our app is not running(in the background OR NOT RUNNING AT ALL), the server would still send a message to that Firebase topic and iOS will receive it.
My question is, how can I intercept a notification, and check whether it should be presented and silent it if needed? I need to support iOS 9 as well so UNNotificationServiceExtension does not suit my needs.
Thanks.
That's a great question and currently there is no solution for this problem o iOS.
You can read about this on the Apple guide for local and push notifications.
https://developer.apple.com/library/content/documentation/NetworkingInternet/Conceptual/RemoteNotificationsPG/
PS: If by silent you meant change the sound that the notification makes, you can do it. https://developer.apple.com/library/content/documentation/NetworkingInternet/Conceptual/RemoteNotificationsPG/ModifyingNotifications.html#//apple_ref/doc/uid/TP40008194-CH16-SW1

Notification - when app is killed

I have implemented AWS SNS push notification service.
We have an issue which is explained below :
Scenario :
We are trying to save the notification message we receive as a part of requirement.
When the app is killed (swipe out from recent apps) we are able to receive notification, also we are able to save the notification message when we open the message directly from the notification panel it works fine,but when we open the app directly the notification message is not getting saved.
In short we are not able to know if we had received a notification message if we directly open the app rather than clicking the message from the notification panel.
Is this default behavior ? or is there any work around for this ?
Have looked into many posts on about Push Notifications but haven't seen any threads pointing to this scenario.
This is a normal behavior, and there is no workaround.
If your app is killed by the user, it won't be able to run ANY code before it's manually launched again.
If it's manually launched from a notification, this notification's payload will be handled by your AppDelegate.
On top of that, don't forget that Push notifications are Best Effort. That means that they are not reliable, they can be heavily delayed or never delivered at all. Don't rely on Push notifications to achieve any critical work.
If you need to keep a copy of your notifications in-app, keep them server side and fetch them as you would do with any other object.
In order to execute code when the app is killed by the user you need to implement VOIP using PushKit framework provided by apple.
VOIP push unlike regular push notification enables the app to become active even if the app is killed by user.

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