UICollectionView在重新加载时返回Nil

Question

我有一个UICollectionView，并且在我的customCell 3按钮中存在

第一次重新加载数据时，一切都很好，但是在重新加载数据时，其中一个按钮返回nil

怎么了？

我该怎么办？

func collectionView(_ collectionView: UICollectionView,cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
    let reuseIdentifier = "ProductCollectionViewCell"
    let cell = collectionView.dequeueReusableCell(withReuseIdentifier: reuseIdentifier,for: indexPath) as! ProductCollectionViewCell

    let product = realm.objects(ProductModelDB.self)
    for i in 0..<product.count {
        if product[i].id == self.productsArray[indexPath.row].id {
            productsArray[indexPath.row].count = product[i].count
        }
    }

    let object = productsArray[indexPath.row]

    let url:URL! = URL(string: (object.mainImageUrl))
    cell.productImage.kf.setImage(with: url)
    cell.nameLabel.text = object.name
    cell.brandLabel.text = object.brandName

    if object.isSelected {
        cell.addingView.alpha = 1
    }else{
        cell.addingView.alpha = 0
    }
    cell.numberLabel.text = "\(object.count)"

    cell.plusBtn.addTarget(self, action: #selector(plus(_:)), for: .touchUpInside)
    cell.plusBtn.tag = indexPath.row

    cell.minusBtn.addTarget(self, action: #selector(minus(_:)), for: .touchUpInside)
    cell.minusBtn.tag = indexPath.row

    cell.addingButton.addTarget(self, action: #selector(adding(_:)), for: .touchUpInside)
    cell.addingButton.tag = indexPath.row

    cell.ui()

    return cell
}