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

According to n13's solution, I made a swift3 version.

Hopes it could help some people like me.

import Foundation
import UIKit
import ObjectiveC

var ActionBlockKey: UInt8 = 0

// a type for our action block closure
typealias BlockButtonActionBlock = (_ sender: UIButton) -> Void

class ActionBlockWrapper : NSObject {
    var block : BlockButtonActionBlock
    init(block: @escaping BlockButtonActionBlock) {
        self.block = block
    }
}

extension UIButton {
    func block_setAction(block: @escaping BlockButtonActionBlock, for control: UIControlEvents) {
        objc_setAssociatedObject(self, &ActionBlockKey, ActionBlockWrapper(block: block), objc_AssociationPolicy.OBJC_ASSOCIATION_RETAIN_NONATOMIC)
        self.addTarget(self, action: #selector(UIButton.block_handleAction), for: .touchUpInside)
    }

    func block_handleAction(sender: UIButton, for control:UIControlEvents) {

        let wrapper = objc_getAssociatedObject(self, &ActionBlockKey) as! ActionBlockWrapper
        wrapper.block(sender)
    }
}