Custom TableViewCell lose its own variable when scrolling - ios

Question

I have the following Custom TableViewCell
The red(minus) and green(plus) button counts the left label "1"(in code snippet var myQuantity). If I scroll up and down in the tableView the variable myQuantity is always reset to 1 for selected cells.
I read that I have to set the myQuantity in the cellForRowAt method. But how can I set the cell value with its own class variable when its changed via green and red button?
Here my Custom Cell Class:
class ArticleTableViewCell: UITableViewCell {
#IBOutlet var leftLabel: UILabel!
#IBOutlet var rightLabel: UILabel!
#IBOutlet var quantityLabel: UILabel!
var myQuantity = 0
override func awakeFromNib() {
super.awakeFromNib()
// Initialization code
self.quantityLabel.text = String(self.myQuantity)
self.leftLabel.sizeToFit()
self.rightLabel.sizeToFit()
}
override func setSelected(_ selected: Bool, animated: Bool) {
super.setSelected(selected, animated: animated)
if selected {
self.myQuantity = 1
} else {
self.myQuantity = 0
}
self.quantityLabel.text = String(self.myQuantity)
}
#IBAction func addButton(_ sender: UIButton) {
if !self.isSelected { return }
self.myQuantity += 1
self.quantityLabel.text = String(self.myQuantity)
}
#IBAction func minusButton(_ sender: UIButton) {
if !self.isSelected { return }
if self.myQuantity == 1 { return }
self.myQuantity -= 1
self.quantityLabel.text = String(self.myQuantity)
}}
Here the cellForRowAt Method in my ViewController:
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
if let cell = tableView.dequeueReusableCell(withIdentifier: "customArticleCell", for: indexPath) as? ArticleTableViewCell {
let name: String! = categoryArticles[indexPath.row].name
let price = categoryArticles[indexPath.row].price
let price2f = String(format: "%.2f", price)
cell.accessoryType = .none
cell.leftLabel.text = name!
cell.rightLabel.text = "\(price2f) €"
if cell.isSelected {
cell.accessoryType = .checkmark
}
return cell
}
}

Answer 1

class ArticleTableViewCell: UITableViewCell {
#IBOutlet var leftLabel: UILabel!
#IBOutlet var rightLabel: UILabel!
#IBOutlet var quantityLabel: UILabel!
var addAction: (()->())?
var minusAction: (()->())?
override func awakeFromNib() {
super.awakeFromNib()
self.selectionStyle = .none
}
func setupCellWith(data: CategoryArticle) {
self.accessoryType = (data.isSelected == true) ? .checkmark : .none
self.leftLabel.text = data.name
let price2f = String(format: "%.2f", data.price)
self.rightLabel.text = "\(price2f) €"
}
#IBAction func addButton(_ sender: UIButton) {
self.addAction?()
}
#IBAction func minusButton(_ sender: UIButton) {
self.minusAction?()
}
}
struct CategoryArticle {
let name: String
let price: Double
var isSelected: Bool?
var quantity: Int?
}
let categoryArticles: [CategoryArticle] = []
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "customArticleCell", for: indexPath) as! ArticleTableViewCell
let categoryArticle = categoryArticles[indexPath.row]
cell.setupCellWith(data: categoryArticle)
cell.minusAction = { [weak self] in
// Action you want to do like decrease the count in the model at indexPath.row and set selection in th model too and reload the tableView cell
}
cell.addAction = { [weak self] in
// Action you want to do like increase the count in the model at indexPath.row and set selection in th model too and reload the tableView cell
}
return cell
}