How to remove notification from backend sent to iPhone when app is killed by User

Question

Like WhatsApp, I am going to implement a web interface for an iPhone application. If a user logged in on both environments(iPhone & web) and receives a message from another user, a notification is sent to the iPhone and web. When the user reads that message from the web interface, notification sent to iPhone should be removed as WhatsApp does even when the iPhone app is killed.

How can we remove that iPhone sent notification from backend? As I know we don't have control on iPhone app when app is killed by User.

Thanks in advance.

See the below answer for how silent notification works. https://stackoverflow.com/questions/36694963/what-is-silent-push-notification-when-does-the-device-receive-it — jogshardik, May 09 '19 at 12:45

jogshardik · Answer 1 · 2019-05-08T11:42:09.613

2

I don't know how whatsapp manages this but you can use silent notification to achieve the above feature.You need to turn on the background mode for silent notification.

When Silent notification comes it doesn't show up on screen like regular notification it will open your application even if your app in terminated mode. The system will provide some time to your app to perform certain task and you can do in that time frame only.

func application(_ application: UIApplication, didReceiveRemoteNotification userInfo: [AnyHashable: Any], fetchCompletionHandler completionHandler: @escaping (UIBackgroundFetchResult) -> Void) {
       print(" Entire message \(userInfo)")
       print("Article avaialble for download: \(userInfo["articleId"]!)")
       //let timer = Timer.scheduledTimer(timeInterval: 1.0, target: self, selector: #selector(scheduleLocalNotification), userInfo: nil, repeats: false)
       let state: UIApplication.State = application.applicationState
       switch state {
       case UIApplicationState.active:
           print("If needed notify user about the message")
       default:
           registerBackgroundTask()
           removeBadges()
    }
    completionHandler(UIBackgroundFetchResult.newData)
}
func registerBackgroundTask() {
       backgroundTask = UIApplication.shared.beginBackgroundTask { [weak self] in
       self?.endBackgroundTask()
   }
   assert(backgroundTask != UIBackgroundTaskIdentifier.invalid)
}

func endBackgroundTask() {
  print("Background task ended.")
  UIApplication.shared.endBackgroundTask(backgroundTask)
  backgroundTask = UIBackgroundTaskIdentifier.invalid
}
func removeBadge() {           
  UIApplication.shared.applicationIconBadgeNumber = 0           
  UIApplication.shared.cancelAllLocalNotifications()
}

edited May 08 '19 at 11:42

answered May 08 '19 at 11:02

jogshardik

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Will didReceiveRemoteNotification call when app is killed? – atifali May 08 '19 at 11:10
Yes it will open in killed mode also. You can check this by running Local notification code when you receive silent notification. – jogshardik May 08 '19 at 11:43
Let me test implement and test the above scenario. – atifali May 09 '19 at 07:36
I have checked above solution and confirmed as I already know that didReceiveRemoteNotification not called when app is killed. – atifali May 09 '19 at 11:57
See the below answer https://stackoverflow.com/questions/36694963/what-is-silent-push-notification-when-does-the-device-receive-it – jogshardik May 09 '19 at 12:44
See this article, https://medium.com/fantageek/push-notification-in-ios-46d979e5f7ec – atifali May 09 '19 at 14:54
This solution works only when app is in background. I am specifically talking about when app is killed by user. – atifali May 09 '19 at 15:08
Please read some document about silent notification and how it works. – jogshardik May 09 '19 at 19:19

score 1 · Accepted Answer · answered May 09 '19 at 15:25

1

What's app is a VoIP app and it's always (in a way) awake in the background. So one can perform api calls to check status of the application messages. If your app has a VoIP feature, you can benefit from it.

answered May 09 '19 at 15:25

Shrey

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Yes this makes sense. – atifali May 09 '19 at 18:11
Thanks, it is only possible using VoIP. – atifali May 10 '19 at 08:02
but app is not approved by Apple if we use VoIP notification. – atifali Oct 29 '19 at 13:20
1

Yes, your app needs to be a VoIP app to use VoIP notifications, otherwise apple will reject the app – Shrey Oct 29 '19 at 18:34

score 1 · Answer 3 · answered Sep 14 '19 at 09:07

1

Try using VoIP Pushes, silent push notification wont work if app was intentionally terminated by user.

answered Sep 14 '19 at 09:07

archilo20

41
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Yes this approach was successful – atifali Sep 16 '19 at 08:44

How to remove notification from backend sent to iPhone when app is killed by User

3 Answers3