Introduction

If you start a project from scratch, you need to always create some kind of service like PushNotificationService that will be responsible for handling push notification events. In this article, I want to explore a simple implementation of PushNotificationService to be able to reuse and customize it in future projects.

First Step

The first step is to add the Push Notifications capability to your project. Go to your project -> Signing & Capabilities -> Tap + Capability -> Search for Push Notifications.

Second Step

The second step is to register push notifications.

func application(_: UIApplication, didFinishLaunchingWithOptions _: [UIApplication.LaunchOptionsKey: Any]? = nil) -> Bool {
    pushNotificationService.registerPushNotifications()
    return true
}

Third Step

The third step is to add didRegisterForRemoteNotificationsWithDeviceToken and didFailToRegisterForRemoteNotificationsWithError to the AppDelegate file and pass the information that occurred to PushNotificationService.

func application(_: UIApplication, didRegisterForRemoteNotificationsWithDeviceToken deviceToken: Data) {
    pushNotificationService.didRegisterForRemoteNotificationsWithDeviceToken(deviceToken: deviceToken)
}

func application(_: UIApplication, didFailToRegisterForRemoteNotificationsWithError error: Error) {
    pushNotificationService.didFailToRegisterForRemoteNotificationsWithError(error: error)
}

Complete Example

import UIKit

class AppDelegate: NSObject, UIApplicationDelegate {
    private let pushNotificationService = PushNotificationService()

    func application(_: UIApplication, didFinishLaunchingWithOptions _: [UIApplication.LaunchOptionsKey: Any]? = nil) -> Bool {
        pushNotificationService.registerPushNotifications()
        return true
    }

    func application(_: UIApplication, didRegisterForRemoteNotificationsWithDeviceToken deviceToken: Data) {
        pushNotificationService.didRegisterForRemoteNotificationsWithDeviceToken(deviceToken: deviceToken)
    }

    func application(_: UIApplication, didFailToRegisterForRemoteNotificationsWithError error: any Error) {
        pushNotificationService.didFailToRegisterForRemoteNotificationsWithError(error: error)
    }
}

import UIKit

public final class PushNotificationService: NSObject {
    public func registerPushNotifications() {
        UNUserNotificationCenter.current().requestAuthorization(options: [.alert, .sound, .badge]) {
            granted, _ in
            guard granted else { return }
            DispatchQueue.main.async {
                UIApplication.shared.registerForRemoteNotifications()
            }
        }
    }

    public func didRegisterForRemoteNotificationsWithDeviceToken(deviceToken: Data) {
        let token = deviceToken.map { String(format: "%02.2hhx", $0) }.joined()
        print("Device token: \(token)")
    }

    public func didFailToRegisterForRemoteNotificationsWithError(error: any Error) {
        print("Failed to register for remote notifications: \(error)")
    }
}

Thank you for reading! 😊