TableViewCell 中 UIButton 的 addTarget 不起作用

Question

I'm making a table view app, and have created UITableViewCell programmatically. The cell consists of 2 views, the first one for the Label, and the second one is for 2 buttons and label. Pressing on the button should change the label's title. Also, I'm using delegates to implement logic in the view controller. Here is my cell code. Sorry for the mess with the constraints. I'm only learning to implement them nicely.

protocol FinalCellDelegate {
    func addButtonPressed(sender: UIButton)
    func subtactButtonPressed(sender: UIButton)
}


class FinalCell: UITableViewCell {
  let label = UILabel()
  var addButton = UIButton()
  var numberLabel = UILabel()
  var subtractButton = UIButton()
  var delegate: FinalCellDelegate?


  override func awakeFromNib() {
       super.awakeFromNib()

   }

   override init(style: UITableViewCell.CellStyle, reuseIdentifier: String?) {
        super.init(style: style, reuseIdentifier: "FinalCell")


        contentView.addSubview(label)
        let addAndSubtractView = UIView()
        addAndSubtractView.addSubview(addButton)
        addAndSubtractView.addSubview(numberLabel)
        addAndSubtractView.addSubview(subtractButton)
        contentView.addSubview(addAndSubtractView)

        //constraints
        addButton.translatesAutoresizingMaskIntoConstraints = false
        addButton.trailingAnchor.constraint(equalTo: addAndSubtractView.trailingAnchor, constant: -15).isActive = true
        addButton.leadingAnchor.constraint(equalTo: numberLabel.trailingAnchor, constant: 10).isActive = true
        addButton.centerYAnchor.constraint(equalTo: contentView.centerYAnchor).isActive = true
        subtractButton.translatesAutoresizingMaskIntoConstraints = false
        subtractButton.leadingAnchor.constraint(equalTo: addAndSubtractView.leadingAnchor, constant: 10).isActive = true
        subtractButton.trailingAnchor.constraint(equalTo: numberLabel.leadingAnchor, constant: -10).isActive = true
        subtractButton.centerYAnchor.constraint(equalTo: contentView.centerYAnchor).isActive = true
        numberLabel.translatesAutoresizingMaskIntoConstraints = false
        numberLabel.centerYAnchor.constraint(equalTo: contentView.centerYAnchor).isActive = true
        addAndSubtractView.translatesAutoresizingMaskIntoConstraints = false
        addAndSubtractView.trailingAnchor.constraint(equalTo: contentView.trailingAnchor, constant: -5).isActive = true
        addAndSubtractView.centerYAnchor.constraint(equalTo: contentView.centerYAnchor).isActive = true
        label.translatesAutoresizingMaskIntoConstraints = false
        label.leadingAnchor.constraint(equalTo: contentView.leadingAnchor, constant: 20).isActive = true
        label.centerYAnchor.constraint(equalTo: contentView.centerYAnchor).isActive = true


        label.textColor = .black
        subtractButton.setTitle("-", for: .normal)
        subtractButton.setTitleColor(.black, for: .normal)
        addButton.setTitle("+", for: .normal)
        addButton.setTitleColor(.black, for: .normal)
        numberLabel.text = "0"
        numberLabel.textColor = .black

        subtractButton.addTarget(self, action: #selector(subtractButtonTapped(_:)), for: .touchUpInside)
        addButton.addTarget(self, action: #selector(addButtonTapped(_:)), for: .touchUpInside)
}

  @objc func addButtonTapped(_ sender: UIButton) {
      print("addButtonTapped")
       delegate?.addButtonPressed(sender: sender)
   }

   @objc func subtractButtonTapped(_ sender: UIButton) {
       print("subtractButtonTapped")
       delegate?.subtactButtonPressed(sender: sender)
   }

   }

Here is my cellForRow at indexPath code:

func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCell(withIdentifier: "FinalCell", for: indexPath) as! FinalCell
        cell.delegate = self
        cell.cellTag = indexPath.row
        cell.addButton.tag = indexPath.row
        cell.subtractButton.tag = indexPath.row

        return cell
    }

And of course delegate implementation:

extension FinalGameSettings: FinalCellDelegate {

    func addButtonPressed(sender: UIButton) {
        print("works")
    }
    func subtactButtonPressed(sender: UIButton) {
        print("This works too")
}
}

The problem is, that when I press on Button - nothing happens. Please, give me a piece of advice to handle the problem!

Answer 1

I copy your project and make my own. After debugging, i found this. The button in your view is not inside the view addAndSubtractView . So that means you can't click it. And your addAndSubtractView does not show in the cell, It's hidden somewhere.

po addButton.frame
▿ (60.0, -17.0, 30.0, 34.0)
  ▿ origin : (60.0, -17.0)
    - x : 60.0
    - y : -17.0
  ▿ size : (30.0, 34.0)
    - width : 30.0
    - height : 34.0

Try fixing your auto-layout. I suggest you try SnapKit framework for better looking