[UIControl Extension Handle Closure] #UIButton #UIControl #extension

ControlClosure.swift

//https://stackoverflow.com/a/41438789/484605

class ControlClosure {
    let closure: ()->()

    init (_ closure: @escaping ()->()) {
        self.closure = closure
    }

    @objc func invoke () {
        closure()
    }
}

extension UIControl {
    func add (for controlEvents: UIControlEvents, _ closure: @escaping ()->()) {
        let sleeve = ControlClosure(closure)
        addTarget(sleeve, action: #selector(ControlClosure.invoke), for: controlEvents)
        objc_setAssociatedObject(self, String(format: "[%d]", arc4random()), sleeve, objc_AssociationPolicy.OBJC_ASSOCIATION_RETAIN)
    }
}

Usage.swift

button.add(for: .touchUpInside) {
    print("Hello, Closure!")
}