Swift: addGestureRecognizer for UIView class

问题:

I use this code:

class StarClass: UIView {
    @IBOutlet weak var bgStar: UIView!

    class func createMyClassView() -> StarClass {
        let myClassNib = UINib(nibName: "Star", bundle: nil)

        let nW = myClassNib.instantiate(withOwner: nil, options: nil)[0] as! StarClass
        nW.bgStar.layer.cornerRadius = 15

        nW.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(handleStar(sender:))))

        return nW
    }

    @objc func handleStar(sender: UITapGestureRecognizer) {
        print("iosLog STAR")
    }
}

After run, if I clicked on the view, I get error below:

2018-07-10 11:11:50.496349+0430 Ma[23098:89853] +[Ma.StarClass handleStarWithSender:]: unrecognized selector sent to class 0x10ef5cac0 2018-07-10 11:11:50.513392+0430 Ma[23098:89853] * Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '+[Ma.StarClass handleStarWithSender:]: unrecognized selector sent to class 0x10ef5cac0' * First throw call stack:...

回答1:

There seems to be a problem with the line :

nW.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(handleStar(sender:))))

Here, inside a class function, self refers to the Class type, not its object. But you are adding the gesture recogniser on an object. The solution here would be to do this:

nW.addGestureRecognizer(UITapGestureRecognizer(target: nW, action: #selector(handleStar(sender:))))