Syntax "Selector" Swift 2.2

Question

I'm trying to fix my NSNotificationCenter and its not working

the message :

'Use of string literal for Objective-C selectors is deprecated; use '#selector' instead'.

the line :

NSNotificationCenter.defaultCenter().addObserver(self, Selector :#selector(GameViewController.goBack)(GameViewController.goBack), object: nil)
        self.dismissViewControllerAnimated(true, completion: {
        });
        }

Answer 1

@Eendje's answer is incorrect by its first comment.

I think it is better answer.

NSNotificationCenter.defaultCenter().addObserver(self, #selector(self.goBack), name: "your notification name", object: nil)

If some actions has target, it should be presented like #selector(target.method) or #selector(target.method(_:))

Here is another example

UIGestureRecognizer(target: target action:#selector(target.handleGesture(_:))

Answer 2

The code you pasted doesn't make any sense:

Selector :#selector(GameViewController.goBack)(GameViewController.goBack) // ???

It should be:

NSNotificationCenter.defaultCenter().addObserver(self, #selector(goBack), name: "your notification name", object: nil)

Answer 3

You have to look at this: https://github.com/apple/swift-evolution/blob/master/proposals/0022-objc-selectors.md

The #selector proposal was made in conjunction with another proposal, specifying swift functions by their argument labels. So if I have a struct:

struct Thing
    func doThis(this: Int, withOtherThing otherThing: Int) {

    }
}

I would reference that function like:

let thing = Thing()
thing.doThis(_:withOtherThing:)

Remember here I'm referencing the function itself, not calling it.

You would use that with #selector:

#selector(self.doThis(_:withOtherThing:)

Function with no arguments:

#selector(self.myFunction)

Function with one implicit argument:

#selector(self.myOtherFunction(_:))