检测哪个 ImageView 已被点击

Question

So i have 4 vStacks, each containing 9 ImageViews . Each ImageView represents one Card, alpha 0 is default. When a Card is Detected (with ARKit ), my code sets the ImageView to alpha 1 so the user can see that the card has been scanned.

Now: I want to implement that when the user clicks on one of the ImageViews , an alert should pop up asking the user if he is sure he wants to delete the scanned card. My problem is, I have no idea what the best practice is to get the information that the card has been tapped and how to delete it without hardcoding.

In ViewDidLoad i set the images into the ImageVies like This:

//This repeats for all 36 ImageViews
imgView1.image = UIImage(named: "Eichel_6")
imgView2.image = UIImage(named: "Eichel_7")

/*When a image is detected with ARKit, this is what happens. Basically
 *it pushes the corresponding reference name to an array called 
 * scannedCards, handles them, and removes them afterwards.
 * spielPoints = gamepoints/points, spielmodus = gamemode
 */

func updateLabel() {
        //print all cards in scanned cards
        for card in scannedCards {
            points += (DataController.shared.spielpoints[DataController.shared.spielmodus!]![card]! * DataController.shared.multCalculator[DataController.shared.spielmodus!]!)
        }
        scannedCards.removeAll()
    }

I am a new to coding, I would be grateful if you correct me if my code snippets are bad, beside my question. Thank you in advance.

Answer 1

As has already been mentioned in comments, you should use a UICollectionView for this kind of work. @Fogmeister has promised to add an answer concerning that later, so I won't do that. But I can answer the actual question, even though it's not what you should do.

From your code I can see that you probably have outlets for all your imageViews (imgView1 ... imgView36) and set each image manually. To detect taps on any of these, you could do something like this:

func viewDidLoad(){
    super.viewDidLoad()
    let allImageViews = [imageView1, imageView2, .... imageView36]
    let tapGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(didTapImageView(gesture:)))
    allImageViews.forEach({$0.addGestureRecognizer(tapGestureRecognizer)})
}

@objc func didTapImageView(gesture:UITapGestureRecognizer){
    guard let imageView = gesture.view as? UIImageView else { return }

    //Here you can put code that will happen regardless of which imageView was tapped.
    imageView.alpha = 0.0

    //If you need to know exactly which imageView was tapped, you can just check
    if imageView == self.imageView1{
        //Do stuff only for imageView1
    }else if imageView == self.imageView2{
        //...
    }//....
}

Again, this is not very good practice. If you go for UICollectionView instead, you don't have to have outlets for all your imageViews and you don't have to create a gestureRecognizer for handling events. But still, I hope this helped you understand general gestures better.