Push notifications (APNs + FCM) in iOS Swift - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to request user permission for push notifications in Swift.

iOS Swift

UNUserNotificationCenter.current().requestAuthorization(options: [.alert, .sound, [1]]) { granted, error in
    if granted {
        print("Permission granted")
    }
}

Drag options to blanks, or click blank then click option'

A.calendar

B.location

C.badge

D.contacts

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing unrelated options like location or contacts which are not notification permissions.

The .badge option allows the app to show badge counts on the app icon, which is part of push notification permissions.

2fill in blank

medium

Complete the code to register for remote notifications after permission is granted.

iOS Swift

DispatchQueue.main.async {
    UIApplication.shared.[1]()
}

Drag options to blanks, or click blank then click option'

AregisterUserNotificationSettings

BregisterForRemoteNotifications

CbeginBackgroundTask

DopenSettingsURLString

Attempts:

3 left

💡 Hint

Common Mistakes

Using deprecated or unrelated methods like registerUserNotificationSettings.

The method registerForRemoteNotifications() tells iOS to start receiving push notifications from APNs.

3fill in blank

hard

Fix the error in the delegate method to receive the device token for APNs.

iOS Swift

func application(_ application: UIApplication, didRegisterForRemoteNotificationsWithDeviceToken [1]: Data) {
    let tokenParts = [2].map { data in String(format: "%02.2hhx", data) }
    let token = tokenParts.joined()
    print("Device Token: \(token)")
}

Drag options to blanks, or click blank then click option'

AdeviceToken

BnotificationToken

CtokenData

DpushToken

Attempts:

3 left

💡 Hint

Common Mistakes

Using incorrect parameter names causes the delegate method not to be called.

The parameter name must be deviceToken to match the delegate method signature exactly.

4fill in blank

hard

Fill both blanks to create a dictionary payload for Firebase Cloud Messaging (FCM) with a notification title and body.

iOS Swift

let message: [String: Any] = [
    "notification": [
        "title": [1],
        "body": [2]
    ]
]

Drag options to blanks, or click blank then click option'

A"Hello"

B"Welcome to the app!"

C"Goodbye"

D"Error occurred"

Attempts:

3 left

💡 Hint

Common Mistakes

Using non-string values or forgetting quotes around strings.

The notification dictionary requires string values for title and body. Here, "Hello" is the title and "Welcome to the app!" is the body.

5fill in blank

hard

Fill all three blanks to handle receiving a push notification in the app delegate and print its content.

iOS Swift

func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void) {
    let userInfo = notification.[1].request.content.[2]
    print("Received notification with info: \(userInfo)")
    completionHandler([3])
}

Drag options to blanks, or click blank then click option'

Adelegate

Bcontent

C[.alert, .sound]

DuserInfo

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong property names or forgetting to call the completion handler.

The notification parameter has a request property, which has content. The content contains userInfo dictionary with the notification data. The completion handler is called with presentation options like [.alert, .sound] to show the notification while the app is in foreground.