The best way to toggle severals UIButtons with same images - swift

Question

In my app I'm using UIButton as check button. I have around 10 UIButton which all should toggle between two Image. An image which shows a "x" and another which shows a check mark. I have an action event for each UIButton, but since all 10 UIButton toggle between two images, is there a way to achieve this the best way. Right now I only know this solution, where I have a Boolean flag for each button and when toggle I set the flag to either true or false. But for me this seems like a bad practice.
Example for one of the UIButton:
var MenuBtnSelect = false
func GlutenSelect(sender: AnyObject)
{
if(!MenuBtnSelect)
{
sender.setImage(UIImage(named: "CheckMark"), forState: .Normal)
MenuBtnSelect = true
}
else
{
sender.setImage(UIImage(named: "NotCheckMark"), forState: .Normal)
MenuBtnSelect = false
}
}

Answer 1

First of all you have to set the NotCheckMark image for every button, then you can create the same without the boolean flag.
#IBAction func pushAnyButton(sender: AnyObject) {
if let btnImage : UIButton = sender as? UIButton {
if (btnImage.currentImage == UIImage(named: "CheckMark"))
{
btnImage.setImage(UIImage(named: "NotCheckMark"), forState: .Normal)
}
else
{
btnImage.setImage(UIImage(named: "CheckMark"), forState: .Normal)
}
}
}
You can use this function for all the 10 button if you connect this method to the buttons. Or you can this in more compact way like this:
#IBOutlet weak var anyCheckBoxButton: UIButton!
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
anyCheckBoxButton.setImage(UIImage(named: "CheckMark"), forState: .Selected )
anyCheckBoxButton.setImage(UIImage(named: "NotCheckMark"), forState: .Normal )
}
#IBAction func pushAnyCheckBoxButton(sender: AnyObject) {
anyCheckBoxButton.selected = !anyCheckBoxButton.selected
}
The second idea came from here.

Answer 2

Just give every button you want to use as a check mark a tag = 1000. if sender.tag == 1000 it is off, set it to 1001 and change the image. Try like this:
import UIKit
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
#IBAction func switchImage(sender: UIButton) {
sender.toggleSwitch
}
}
extension UIButton {
var toggleSwitch: Bool {
if tag == 1000 {
tag = 1001
setImage(UIImage(named: "CheckMark"), forState: .Normal)
return true
} else {
tag = 1000
setImage(UIImage(named: "NotCheckMark"), forState: .Normal)
return false
}
}
}