ViewController.swift

import UIKit

class ViewController: UIViewController {

    var count = 1
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // Button 1
        let button = UICallbackButton(frame: CGRect(x: 60, y: 30, width: 200, height: 60))
        button.backgroundColor = UIColor.orangeColor()
        button.setTitleColor(UIColor.whiteColor(), forState: .Normal)
        button.setTitle("Title Default", forState: .Normal)
        button.on(.TouchUpInside, then: {
            button.setTitle("Title \(self.count)", forState: .Normal)
            self.count = self.count + 1
        })
        
        self.view.addSubview(button)
        
        
        // Button 2
        let button1 = UICallbackButton(frame: CGRect(x: 60, y: 160, width: 200, height: 60))
        button1.backgroundColor = UIColor.blackColor()
        button1.setTitleColor(UIColor.whiteColor(), forState: .Normal)
        button1.setTitle("Value Default", forState: .Normal)
        button1.on(.TouchUpInside, then: {
            button1.setTitle("Value \(self.count)", forState: .Normal)
            self.count = self.count + 1
        })
        
        self.view.addSubview(button1)
        
    }
    
    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

}


typealias ButtonCallback = (() -> ())

protocol UIActionButton {
    
    func on(event : UIControlEvents, then callback: ButtonCallback)
    
}

final class UICallbackButton : UIButton, UIActionButton {
    
    var buttonCallback: ButtonCallback!
    
    func on(event : UIControlEvents, then callback: () -> ()) {
        buttonCallback = callback
        self.addTarget(self, action: #selector(UICallbackButton.executeCallback(_:)), forControlEvents: event)
        
    }
    
    func executeCallback (_ : UIButton) {
        buttonCallback()
    }
}