Joe Anthony Joe Anthony - 11 months ago 112
Swift Question

How to remove the nearly matches optional requirement warning from didRegisterForRemoteNotificationsWithDeviceToken function ios swift 3?

Since I updated my xcode to xcode 8 I am getting this warning :

Instance method

nearly matches optional requirement
:didRegisterForRemoteNotificationsWithDeviceToken:)' of
protocol 'UIApplicationDelegate

Xcode is asking me to silence this warning by making this function private, but when i do the function is never been called (It is not being called in either ways).

I tried to delete the functions then making autocomplete fill it but nothing worked.

This is the function having the warning:

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

This is my complete appDelegate file:


class AppDelegate: UIResponder,UIApplicationDelegate,UNUserNotificationCenterDelegate,CLLocationManagerDelegate {

var window: UIWindow?
var locationManager:CLLocationManager?
var coordinate: CLLocationCoordinate2D?
func locationManagerStart() {

if locationManager == nil {
print("init locationManager")
locationManager = CLLocationManager()
locationManager!.delegate = self
locationManager!.desiredAccuracy = kCLLocationAccuracyBest

print("have location manager")

func locationManagerStop() {

func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
let newLocation = locations.first!
coordinate = newLocation.coordinate
print("location updated")

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


func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {


return true
func registerForPushNotifications(_: UIApplication) {

if #available(iOS 10.0, *){
UNUserNotificationCenter.current().delegate = self

UNUserNotificationCenter.current().requestAuthorization(options: [.badge, .sound, .alert], completionHandler: {(granted, error) in
if (granted)


//Do stuff if unsuccessful...



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

print("i am not available in simulator \(error)")


func application(_ application: UIApplication, didReceiveRemoteNotification userInfo: [AnyHashable: Any]) {


func applicationWillResignActive(_ application: UIApplication) {
// Sent when the application is about to move from active to inactive state. This can occur for certain types of temporary interruptions (such as an incoming phone call or SMS message) or when the user quits the application and it begins the transition to the background state.
// Use this method to pause ongoing tasks, disable timers, and throttle down OpenGL ES frame rates. Games should use this method to pause the game.

func applicationDidEnterBackground(_ application: UIApplication) {
// Use this method to release shared resources, save user data, invalidate timers, and store enough application state information to restore your application to its current state in case it is terminated later.
// If your application supports background execution, this method is called instead of applicationWillTerminate: when the user quits.

func applicationWillEnterForeground(_ application: UIApplication) {
// Called as part of the transition from the background to the inactive state; here you can undo many of the changes made on entering the background.

func applicationDidBecomeActive(_ application: UIApplication) {
// Restart any tasks that were paused (or not yet started) while the application was inactive. If the application was previously in the background, optionally refresh the user interface.

func applicationWillTerminate(_ application: UIApplication) {
// Called when the application is about to terminate. Save data if appropriate. See also applicationDidEnterBackground:.
// Saves changes in the application's managed object context before the application terminates.

// MARK: - Core Data stack

lazy var applicationDocumentsDirectory: URL = {
// The directory the application uses to store the Core Data store file. This code uses a directory named "com.youcode.Hebr" in the application's documents Application Support directory.
let urls = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)
return urls[urls.count-1]

lazy var managedObjectModel: NSManagedObjectModel = {
// The managed object model for the application. This property is not optional. It is a fatal error for the application not to be able to find and load its model.
let modelURL = Bundle.main.url(forResource: "Hebr", withExtension: "momd")!
return NSManagedObjectModel(contentsOf: modelURL)!

lazy var persistentStoreCoordinator: NSPersistentStoreCoordinator = {
// The persistent store coordinator for the application. This implementation creates and returns a coordinator, having added the store for the application to it. This property is optional since there are legitimate error conditions that could cause the creation of the store to fail.
// Create the coordinator and store
let coordinator = NSPersistentStoreCoordinator(managedObjectModel: self.managedObjectModel)
let url = self.applicationDocumentsDirectory.appendingPathComponent("SingleViewCoreData.sqlite")
var failureReason = "There was an error creating or loading the application's saved data."
do {
try coordinator.addPersistentStore(ofType: NSSQLiteStoreType, configurationName: nil, at: url, options: nil)
} catch {
// Report any error we got.
var dict = [String: AnyObject]()
dict[NSLocalizedDescriptionKey] = "Failed to initialize the application's saved data" as AnyObject?
dict[NSLocalizedFailureReasonErrorKey] = failureReason as AnyObject?

dict[NSUnderlyingErrorKey] = error as NSError
let wrappedError = NSError(domain: "YOUR_ERROR_DOMAIN", code: 9999, userInfo: dict)
// Replace this with code to handle the error appropriately.
// abort() causes the application to generate a crash log and terminate. You should not use this function in a shipping application, although it may be useful during development.
NSLog("Unresolved error \(wrappedError), \(wrappedError.userInfo)")

return coordinator

lazy var managedObjectContext: NSManagedObjectContext = {
// Returns the managed object context for the application (which is already bound to the persistent store coordinator for the application.) This property is optional since there are legitimate error conditions that could cause the creation of the context to fail.
let coordinator = self.persistentStoreCoordinator
var managedObjectContext = NSManagedObjectContext(concurrencyType: .mainQueueConcurrencyType)
managedObjectContext.persistentStoreCoordinator = coordinator
return managedObjectContext

// MARK: - Core Data Saving support

func saveContext () {
if managedObjectContext.hasChanges {
do {
} catch {
// Replace this implementation with code to handle the error appropriately.
// abort() causes the application to generate a crash log and terminate. You should not use this function in a shipping application, although it may be useful during development.
let nserror = error as NSError
NSLog("Unresolved error \(nserror), \(nserror.userInfo)")


Answer Source

After weeks of searching finally solved! The problem was that I had a class named "Data", it didnot make any error in xcode 7 but whenever i add it in xcode 8 the registerForNotification function in the app delegate makes this error! Weird but finally solved by just changing the name of the class Data.