Hooking up UIButton to closure? (Swift, target-action)

Question

I want to hook up a UIButton to a piece of code – from what I have found, the preferred method to do this in Swift is still to use the addTarget(target: AnyObject?, ac

Answer 1

The associatedObject and wrapping and pointers and import of ObjectiveC are unnecessary, at least in Swift 3. This works great and is much more Swift-y. Feel free to throw a typealias in there for () -> () if you find it more readable, bit I find it easier to read the block signature directly.

import UIKit

class BlockButton: UIButton {
    fileprivate var onAction: (() -> ())?

    func addClosure(_ closure: @escaping () -> (), for control: UIControlEvents) {
        self.addTarget(self, action: #selector(actionHandler), for: control)
        self.onAction = closure
    }

    dynamic fileprivate func actionHandler() {
        onAction?()
    }
}