Xamarin.iOS
Рекомендации по переносу из UILocalNotification в систему уведомлений пользователей

UserNotifications

1. Вам придется импортировать UserNotifications

    @import UserNotifications;
   

2. Разрешение на подтверждение для localNotification

let center = UNUserNotificationCenter.current()
center.requestAuthorization([.alert, .sound]) { (granted, error) in
    // Enable or disable features based on authorization.
}

3. Теперь мы обновим номер значка значка приложения

    @IBAction  func triggerNotification(){
    let content = UNMutableNotificationContent()
    content.title = NSString.localizedUserNotificationString(forKey: "Tom said:", arguments: nil)
    content.body = NSString.localizedUserNotificationString(forKey: "Hello Mike！Let's go.", arguments: nil)
    content.sound = UNNotificationSound.default()
    content.badge = UIApplication.shared().applicationIconBadgeNumber + 1;
    content.categoryIdentifier = "com.mike.localNotification"
    //Deliver the notification in two seconds.
    let trigger = UNTimeIntervalNotificationTrigger.init(timeInterval: 1.0, repeats: true)
    let request = UNNotificationRequest.init(identifier: "TwoSecond", content: content, trigger: trigger)
   
    //Schedule the notification.
    let center = UNUserNotificationCenter.current()
    center.add(request)
    }
   
    @IBAction func stopNotification(_ sender: AnyObject) {
    let center = UNUserNotificationCenter.current()
    center.removeAllPendingNotificationRequests()
    }