Managing Local & Remote Notifications from different classes

AppDelegate.swift

  // [START receive_message]
    func application(_ application: UIApplication, didReceiveRemoteNotification userInfo: [AnyHashable: Any]) {
        // 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.messaging().appDidReceiveMessage(userInfo)
        // Print full message.
        print(userInfo)
    }
    
    func application(_ application: UIApplication, didReceiveRemoteNotification userInfo: [AnyHashable: Any],
                     fetchCompletionHandler completionHandler: @escaping (UIBackgroundFetchResult) -> Void) {
        // 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.messaging().appDidReceiveMessage(userInfo)
        
        // Print full message.
        print(userInfo)
        
        completionHandler(UIBackgroundFetchResult.newData)
    }
    // [END receive_message]
    func application(_ application: UIApplication, didFailToRegisterForRemoteNotificationsWithError error: Error) {
        print("Unable to register for remote notifications: \(error.localizedDescription)")
    }
    
    // This function is added here only for debugging purposes, and can be removed if swizzling is enabled.
    // If swizzling is disabled then this function must be implemented so that the APNs token can be paired to
    // the FCM registration token.
    func application(_ application: UIApplication, didRegisterForRemoteNotificationsWithDeviceToken deviceToken: Data) {
        print("APNs token retrieved: \(deviceToken)")
        
        // With swizzling disabled you must set the APNs token here.
        // Messaging.messaging().apnsToken = deviceToken
    }

LocalNotificationManager.swift

import UIKit
import UserNotifications

class LocalNotificationManagerDelegate: NSObject, UNUserNotificationCenterDelegate {    
    func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void) {
        // Play sound and show alert to the user
        completionHandler([.alert, .sound])
    }
    
    func userNotificationCenter(_ center: UNUserNotificationCenter, didReceive response: UNNotificationResponse, withCompletionHandler completionHandler: @escaping () -> Void) {
        // Determine the user actions
        completionHandler()
    }
}

class LocalNotificationManager: NSObject {
    
    private override init() {}    
    private static var notificationDelegate = LocalNotificationManagerDelegate()
    
    class func register() {
        let center = UNUserNotificationCenter.current()
        center.requestAuthorization(options: [.alert, .sound]) { (granted, error) in
            if !granted {
                print("failed.")
            }
        }
    }
    
    class func removeNotifications() {
        let center = UNUserNotificationCenter.current()
        center.removeAllDeliveredNotifications()
        center.removeAllPendingNotificationRequests()
    }
    
    class func authorizationStatus(completion: @escaping (_ status: UNAuthorizationStatus, _ authorized: Bool) -> Void) {
        UNUserNotificationCenter.current().getNotificationSettings { (settings) in
            let status = settings.authorizationStatus
            completion(status, status == .authorized)
        }
    }
}

RemoteNotificationManager.swift

class RemoteNotificationManagerDelegate: NSObject, UNUserNotificationCenterDelegate {
    func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void) {
        let userInfo = notification.request.content.userInfo
        print(userInfo)
        // Play sound and show alert to the user
        completionHandler([.alert, .sound])
    }
    
    func userNotificationCenter(_ center: UNUserNotificationCenter, didReceive response: UNNotificationResponse, withCompletionHandler completionHandler: @escaping () -> Void) {
        let userInfo = response.notification.request.content.userInfo
        print(userInfo)
        completionHandler()
    }
}

class RemoteNotificationManagerMessagingDelegate: NSObject, MessagingDelegate {
    func messaging(_ messaging: Messaging, didReceiveRegistrationToken fcmToken: String) {
        print("Firebase registration token: \(fcmToken)")
        // Note: This callback is fired at each app startup and whenever a new token is generated.
    }
    
    // Receive data messages on iOS 10+ directly from FCM (bypassing APNs) when the app is in the foreground.
    // To enable direct data messages, you can set Messaging.messaging().shouldEstablishDirectChannel to true.
    func messaging(_ messaging: Messaging, didReceive remoteMessage: MessagingRemoteMessage) {
        print("Received data message: \(remoteMessage.appData)")
    }

}

class RemoteNotificationManager: NSObject {
    private override init() {}
    
    private static var notificationDelegate = RemoteNotificationManagerDelegate()
    private static var messagingDelegate = RemoteNotificationManagerMessagingDelegate()
    
    class func register() {
        let authOptions: UNAuthorizationOptions = [.alert, .badge, .sound]
        UNUserNotificationCenter.current().requestAuthorization(options: authOptions) { (granted, error) in
            if !granted {
                  print("failed.")
            }
        }
        UIApplication.shared.registerForRemoteNotifications()
    }
    
    class func config() {
        if UIApplication.shared.isRegisteredForRemoteNotifications {
            UNUserNotificationCenter.current().delegate = notificationDelegate
            Messaging.messaging().delegate = messagingDelegate
            Messaging.messaging().shouldEstablishDirectChannel = true
        } else {
            register()
        }
    }
    
    class func clear() {
        UIApplication.shared.applicationIconBadgeNumber = 0
        let center = UNUserNotificationCenter.current()
        center.removeAllDeliveredNotifications()
        center.removeAllPendingNotificationRequests()
    }
    
    class func unregister() {
        UIApplication.shared.unregisterForRemoteNotifications()
    }
}

ViewController.swift

//Using Local and Remote Notificaitons Manager class functions like this

    @objc private func actionManagePushNotifications(switchOption: UISwitch) {
        if switchOption.isOn {
            if !UIApplication.shared.isRegisteredForRemoteNotifications {
                 RemoteNotificationManager.register()
            }
        } else {
            RemoteNotificationManager.clear()
            RemoteNotificationManager.unregister()
        }
    }
    
    @objc private func actionSetBackgroundRefresh(switchOption: UISwitch) {
        if switchOption.isOn {
            LocalNotificationManager.authorizationStatus { [weak self] (status, authorised) in
                if !authorised {
                    LocalNotificationManager.register()
                }
            }

        } else {
            LocalNotificationManager.removeNotifications()
        }
    }

Hi, thanks for coming here to review this code. I am trying to create two classes one is for local notifications (LocalNotificationManager) and one is for remote notifications (RemoteNotificationManager) to manage both types of notifications. I have implemented them in a correct way and seems they are working, however, I am not sure if this is the right (and best) way to manage this.

• It may be possible that I have written so much code here and there which is not require.
• May be someone can suggest to merge both classes into a single class: NotificationsManager, that can handle local as well as remote notifications.
• May be, I don't need some of the delegates which I have implemented?

Requirements: iOS 10.x onwards - No backward compatibility.

If you have any questions feel free to comment here and we'll discuss.

Please advice me on these points and guide me to update it properly. I would appreciate any tip from you!!

Quick review:

It may be possible that I have written so much code here and there which is not require.

I think so , I would try and write as little code as you can, the less there is the less can break ;)

May be someone can suggest to merge both classes into a single class: NotificationsManager, that can handle local as well as remote notifications.

Depends on how you want to use this later, it could probably work as a single class. If you want to keep it split, you should define a protocol that outlines what a Notification manager should do , then inherit from that for each type local and remote. You can use extension on protocols to provide default behaviour if you need it.

May be, I don't need some of the delegates which I have implemented?

What you have called delegates in your code, are not delegates in my mind. I suggest you just inherit from MessagingDelegate etc in the classes directly.

Some notes :

• Keep this stuff within your notification class - https://gist.github.com/hemangshah/0b19d796ea5e46abcb4702db96195321#file-viewcontroller-swift-L5
• You have everything as a class function, try and avoid that.
• Have a go at TDD for this, I think it will help you learn nicer patterns.