Showing/Hiding images in CollectionView Cell

Question

I'm trying to show some images and hide others using ".isHidden" in my CollectionView. But when I scroll down or reload the collectionView they either get reordered incorrectly or hidden entirely.

func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
    let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "ReadBookCell", for: indexPath) as! ReadBookCell
    
    let item = readBookArray[indexPath.item]

        for star in cell.starImgOutletCollection {
            if star.tag <= item.starRating {
                star.isHidden = false

            } else {     
                    star.isHidden = true
            }

        }   

    return cell
}

Edit: Here is my prepareForReuse

 override func prepareForReuse() {
    super.prepareForReuse()
    for star in starImgOutletCollection {
        star.isHidden = true
    }  
}

Answer 1

Assuming your "stars" are 5 image views in a stack view like this:

And, assuming your starRating will be between 0 and 5 (Zero being no rating yet)...

In your cell class, create a reference to the stack view - since your question mentions starImgOutletCollection I'm assuming you are using @IBOutlet (that is, not creating your views via code), so:

@IBOutlet var starsStackView: UIStackView!

Then, still in your cell class, add this func:

func updateStars(_ starRating: Int) {
    for i in 0..<starsStackView.arrangedSubviews.count {
        starsStackView.arrangedSubviews[i].isHidden = i >= starRating
    }
}

Now, in cellForRowAt

func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
    let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "ReadBookCell", for: indexPath) as! ReadBookCell
    
    let item = readBookArray[indexPath.item]

    cell.updateStars(item.starRating)

    // do the other stuff to set labels, images, etc
    //  in the cell    

    return cell
}

You no longer need the outlet collection for the "star" image views, and you no longer need to implement prepareForReuse().