Multiple parameters in NSTimer selector

Question

I would like to pass parameters to the following function through userInfo, because that function has to execute after delay.

func showAlert(alertTitle: String, withMessage alertMessage: String, fromController controller: UIViewController) {
     //do stuff...
}

Have already done that part with delay, but I do not know how to send multiple parameters to the body of showAlert.

func fireTimer() {
   timer = NSTimer.scheduledTimerWithTimeInterval(4, target: self, selector: Selector("showAlert:"), userInfo: nil, repeats: false)
}

Your assistance would be very much appreciated.

---

I'm still getting errors, don't know why.

unrecognized selector sent to instance

This is how my code looks like. What's wrong?

class AlertController: UIAlertController {  
var timer = NSTimer()

func showAlert(alertTitle: String, withMessage alertMessage: String, fromController controller: UIViewController)
{
    var alert = UIAlertController(title: alertTitle, message: alertMessage, preferredStyle: .Alert)
    controller.presentViewController(alert, animated: true, completion: nil)
}

func showAlert2(dict: [String: AnyObject])
{
    showAlert(dict["title"] as! String,
        withMessage: dict["message"] as! String,
        fromController: dict["controller"] as! UIViewController)
}

func fireTimer(title: String, message: String, viewController: UIViewController)
{
    timer = NSTimer.scheduledTimerWithTimeInterval(4, target: self, selector: Selector("showAlert2:"), userInfo: ["title":title, "message": message, "controller": viewController], repeats: false)
}

Answer 1

You cannot pass more than one parameter using NSTimer, however, you can make that parameter into an array or ditionary or similar.

Then create a new function that takes that array/dictionary and then calls your function with every parameter inside the array/dictionary

func fireTimer() {
    timer = NSTimer.scheduledTimerWithTimeInterval(4, target: self, selector: Selector("showAlert2:"), userInfo: ["title":"a title", "message": "a message", "controller": controller], repeats: false)
}

func showAlert2(timer: NSTimer) {   
    let dict = timer.userInfo as NSDictionary

    showAlert(dict["title"] as String, wwithMessage: dict["message"] as String, fromController: dict["controller"] as UIViewController)
}

func showAlert(alertTitle: String, withMessage alertMessage: String, fromController controller: UIViewController) {
//    do stuff...
}