Swift: Unrecognized selector sent to instance with NSTimer

Question

I'm getting server time using Alamofire, and with NSTimer I refresh this time every second.

But I get error

unrecognized selector sent to instance 0x7ff4636126a0'

and also if I change selector to

selector: "getTime:"

, it gives me an error like this.

How should I fix it?

This is my code.

    import UIKit
    import Alamofire

    typealias DownloadComplete = () -> ()

    class ViewController: UIViewController {

        @IBOutlet var currentTime: UILabel!
        var stringDateFromServer = String()
        let dateFormatter = NSDateFormatter()

        override func viewDidLoad() {
            super.viewDidLoad()

            getTime { () -> () in

                self.dateFormatter.dateFormat = "EEE, dd MMM yyyy HH:mm:ss zzz"
                self.dateFormatter.locale = NSLocale(localeIdentifier: "en_US")

                let date2 = self.dateFormatter.dateFromString(self.stringDateFromServer)!

                self.dateFormatter.locale = NSLocale.currentLocale()
                let date3 = self.dateFormatter.stringFromDate(date2)

                self.currentTime.text = date3
            }

            NSTimer.scheduledTimerWithTimeInterval(1, target: self, selector: "getTime", userInfo: nil, repeats: true)

        }

        func getTime(completed: DownloadComplete) {

            let url = NSURL(string: "http://google.com")!

            Alamofire.request(.HEAD, url).responseJSON { (Response) -> Void in

                let result = Response.response

                if let headers = result?.allHeaderFields {
                    if let date = headers["Date"] as? String {
                        self.stringDateFromServer = date

                        }
                    }
                 completed()
            }
        }

    }

Is there any reason why you have an inner and an outer function named `getTime`? Have you tried to name them differently? — Alex, Mar 21 '16 at 12:39
@Alex these names are same because I'm calling exact method..How can I name it differently? — alphonse, Mar 21 '16 at 12:41
@Ro22e0 In the question I wrote that I have already tried it.and also noticed what kind of error I get .read it again :) — alphonse, Mar 21 '16 at 12:42
For the crash see http://stackoverflow.com/questions/24889279/passing-parameters-to-a-method-called-by-nstimer-in-swift: The timer callback must take an `NSTimer` parameter (and this is the correct answer: http://stackoverflow.com/a/26359761/1187415). — Martin R, Mar 21 '16 at 12:48
@Alex inner getTime calls getTime method and updates other values — alphonse, Mar 21 '16 at 13:02
@alphonse I don't see a call to `getTime(completed: DownloadComplete)` from within your inner `getTime` block. — Alex, Mar 21 '16 at 13:06
You can't have a closure as a signature for a method that's called with "selector". — Eric Aya, Mar 21 '16 at 13:08

score 1 · Answer 1 · answered Mar 21 '16 at 13:05

1

You should declare a getTime method in your ViewController.

func getTime () {
    self.dateFormatter.dateFormat = "EEE, dd MMM yyyy HH:mm:ss zzz"
    self.dateFormatter.locale = NSLocale(localeIdentifier: "en_US")

    let date2 = self.dateFormatter.dateFromString(self.stringDateFromServer)!

    self.dateFormatter.locale = NSLocale.currentLocale()
    let date3 = self.dateFormatter.stringFromDate(date2)

    self.currentTime.text = date3
}

answered Mar 21 '16 at 13:05

Misternewb

1,066
9
12

func getTime(completed: DownloadComplete) is declared, they have different signatures. Also you have getTime { () -> () } which is a closure, not a method. – Misternewb Mar 21 '16 at 13:07

Swift: Unrecognized selector sent to instance with NSTimer

1 Answers1