Cannot find protocol declaration for 'UNUserNotificationCenterDelegate' in -Swift.h file

问题

I tried to convert my objective C AppDelegate to Swift AppDelegate. So I deleted the main.m file and Converted all the AppDelegate code to swift. I tried to run the project, then this error occurs.

Cannot find protocol declaration for 'UNUserNotificationCenterDelegate'

In the -Swift.h file they generate, this is the delegate they showed

- (void)userNotificationCenter:(UNUserNotificationCenter * _Nonnull)center willPresentNotification:(UNNotification * _Nonnull)notification withCompletionHandler:(void (^ _Nonnull)(UNNotificationPresentationOptions))completionHandler SWIFT_AVAILABILITY(ios,introduced=10.0);

This is how I have written

@available(iOS 10.0, *)
func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void) {
    handleNotification(notification.request.content.userInfo)
}

Please help me get what is the issue am facing.

I tried, cleaning, restarting Xcode and restarting my Mac. Am using Swift 3.2.

This is my -Swift.h file error

If I comment the delegates, there are no errors.

回答1:

Strange fix but by importing #import in my bridging header the issue was resolved.

回答2:

This is how you need to proceed

import UIKit 
import UserNotifications

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {

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

   /**Register for push notification*/
   func registerForPushNotification() {
       let userNotification = UNUserNotificationCenter.current()
       userNotification.delegate = self
       userNotification.requestAuthorization(options: [.sound, .badge, .alert]) { (status, error) in
        if error == nil {
            DispatchQueue.main.async { // From iOS 10 onwards we need to call pushNotification registration method in main thread.
                UIApplication.shared.registerForRemoteNotifications()
            }
        }
      }
   }

}


// MARK: - UNUserNotificationCenterDelegate methods
extension AppDelegate: UNUserNotificationCenterDelegate {

    func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void) {
        completionHandler([.sound, .badge, .alert])
    }

}

Thanks.

回答3:

You need to import following framework: import UserNotifications

来源：https://stackoverflow.com/questions/49429537/cannot-find-protocol-declaration-for-unusernotificationcenterdelegate-in-swif

标签

ios

objective-c

swift