@selector() in Swift?

Question

I\'m trying to create an NSTimer in Swift but I\'m having some trouble.

NSTimer(timeInterval: 1, target: self, selector: test(), us         


        

Answer 1

When using performSelector()

/addtarget()/NStimer.scheduledTimerWithInterval() methods your method (matching the selector) should be marked as

@objc
For Swift 2.0:
    {  
        //...
        self.performSelector(“performMethod”, withObject: nil , afterDelay: 0.5)
        //...


    //...
    btnHome.addTarget(self, action: “buttonPressed:", forControlEvents: UIControlEvents.TouchUpInside)
    //...

    //...
     NSTimer.scheduledTimerWithTimeInterval(0.5, target: self, selector : “timerMethod”, userInfo: nil, repeats: false)
    //...

}

@objc private func performMethod() {
…
}
@objc private func buttonPressed(sender:UIButton){
….
}
@objc private func timerMethod () {
….
}

For Swift 2.2, you need to write '#selector()' instead of string and selector name so the possibilities of spelling error and crash due to that will not be there anymore. Below is example

self.performSelector(#selector(MyClass.performMethod), withObject: nil , afterDelay: 0.5)