iOS how to detect user has changed system time, and if not compare device time with server time

Question

The requirement is that have to detect if the system time of iPhone is changed by user manually. For that I have used

NSNotificationCenter.defaultCenter         


        

Answer 1

    This code worked for me in Swift 3

    NotificationCenter.default.addObserver(self, selector: #selector(ClassName.timeChangedNotification), name: NSNotification.Name.NSSystemClockDidChange, object: nil)
    }

    // Method get called user changed the system time manually.

    func timeChangedNotification(notification:NSNotification){
        print("Device time has been changed...")
    }