Alternative to UserNotificationCenterDelegate’s willPresent when app is in background

For iOS 10 local notifications your out of luck.

For iOS 10 remote notifications —regardless of user interaction you can receive callbacks using application(_:didReceiveRemoteNotification:fetchCompletionHandler:). (It’s kind of confusing that they deprecated most notification related methods but not this one)

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Callback for when app is in foreground and you’re about to show the notification:

func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void) {
    let content = notification.request.content
    // Process notification content

    completionHandler([.alert, .sound]) // Display notification as regular alert and play sound
}

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Callback for when app is either in background or in foreground and user tapped on an action:

e.g. gives you a callback that user tapped on Save.

func userNotificationCenter(_ center: UNUserNotificationCenter, didReceive response: UNNotificationResponse, withCompletionHandler completionHandler: @escaping () -> Void) {
    let actionIdentifier = response.actionIdentifier

    switch actionIdentifier {
    case UNNotificationDismissActionIdentifier: // Notification was dismissed by user
        // Do something
        completionHandler()
    case UNNotificationDefaultActionIdentifier: // App was opened from notification
        // Do something
        completionHandler()
    default:
        completionHandler()
    }
}

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Callback for when app is either in background, foreground or (possibly) suspended state and a Push Notifications (Remote or silent notification) arrives:

Prior to iOS10 when you tapped on the notification the application(_:didReceiveRemoteNotification:fetchCompletionHandler:) would get called.

But since iOS 10 application(_:didReceiveRemoteNotification:fetchCompletionHandler:) isn’t called upon tapping. It’s only called upon arrival of a remote Notification. (It get’s called both in foreground and in background)

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For pre iOS 10, you can just use the old didReceiveLocalNotification function and capture the arrival of any notification.