当我轻触放置在uitable视图单元中的步进器时，我无法更新标签

Question

这是我设计的图像，这是UITableviewCell的代码，在此我放置了步进动作方法来触发，但是当我点击stepper时无法更新价格标签，有人可以帮助我吗？

class productTableViewCell: UITableViewCell {

    @IBOutlet var stepper: UIStepper!
    @IBOutlet var imageview: UIImageView!
    @IBOutlet var nameLabel: UILabel!
    @IBOutlet var priceLabel: UILabel!
    @IBOutlet var quantityTextField: UITextField!
    var pricearr = [String]()
    var price : String = ""
    override func awakeFromNib() {
        super.awakeFromNib()
        // Initialization code
    }
    @IBAction func changeCart(_ sender: Any) {
        let value = Int(stepper.value)
        quantityTextField.text = String(value)
   }
}

这是UITableViewCell的代码，在其中我放置了要触发的步进动作方法，但是当我点击步进时无法更新价格标签，有人可以帮助我吗？

 @IBOutlet var tableDetails: UITableView!
    var productsArray = [String]()
    var nameArray = [String]()
    var priceArray = [String]()
    let urlstring = "http://www.json-generator.com/api/json/get/ceghMiWudK?indent=2"
    var price = [String]()
    var sum = 0

    override func viewDidLoad() {
        super.viewDidLoad()
       self.downloadJsonWithURL()
        tableDetails.delegate = self
        tableDetails.dataSource = self
        tableDetails.alwaysBounceVertical = false
        // Do any additional setup after loading the view.
    }

    func downloadJsonWithURL() {
            let url = NSURL(string: urlstring)
            URLSession.shared.dataTask(with: (url as? URL)!, completionHandler: {(data, response, error) -> Void in
                if let jsonObj = try? JSONSerialization.jsonObject(with: data!, options: .allowFragments) as? NSDictionary {
                    print(jsonObj!.value(forKey: "Detail"))
                if let detailsArray = jsonObj!.value(forKey: "Detail") as? NSArray {
                    for item in detailsArray {
                        if let detailDict = item as? NSDictionary {
                            if let name = detailDict.value(forKey: "productName"){
                                self.nameArray.append(name as! String)
                            }
                            if let price = detailDict.value(forKey: "productPrice"){
                                self.priceArray.append(price as! String)
                            }
                            if let image = detailDict.value(forKey: "img"){
                                self.productsArray.append(image as! String)
                            }
                        }
                    }
                }
                OperationQueue.main.addOperation({
                    self.tableDetails.reloadData()
                    for item in self.priceArray{
                        let endIndex = item.index(item.endIndex, offsetBy: -5)
                        let truncated = item.substring(to: endIndex)
                        self.price.append(truncated)
                    }
                    print(self.price)
                })
            }
        }).resume()
    }

    func numberOfSections(in tableView: UITableView) -> Int {
        // #warning Incomplete implementation, return the number of sections
        return 3
    }

    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int{
        if (section == 0){
            return productsArray.count
        }else{
            return 1
        }
    }

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        if indexPath.section == 0{
            let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath) as! productTableViewCell
            let arr = self.productsArray[indexPath.row]
            let urls = NSURL(string: arr)
            let data = NSData (contentsOf: urls! as URL)
            cell.imageview.image = UIImage(data: data! as Data)
            cell.nameLabel.text = nameArray[indexPath.row]
            let x = priceArray[indexPath.row]
            let array = String(x)
            cell.priceLabel.text = array
            cell.quantityTextField.text = "1"
            cell.pricearr = [price[indexPath.row]]
            return cell
        }else if indexPath.section == 1{
            let cell = tableView.dequeueReusableCell(withIdentifier: "couponcell", for: indexPath) as! CouponTableViewCell
            return cell
        }else {
            let cell = tableView.dequeueReusableCell(withIdentifier: "checkout", for: indexPath) as! checkoutTableViewCell
            return cell
        }
    }

Answer 1

我认为问题在于以下几行

 priceLabel.text = x * String(value)

您想在这里完成什么？ 这不应该编译

Answer 2

添加步进器的输出口和操作，如下图所示：

将您的代码替换为以下代码之一：

 class productTableViewCell: UITableViewCell {

            @IBOutlet var stepper: UIStepper!
            @IBOutlet var imageview: UIImageView!
            @IBOutlet var nameLabel: UILabel!
            @IBOutlet var priceLabel: UILabel!
            @IBOutlet var quantityTextField: UITextField!
            var pricearr = [String]()
            var price : String = ""
            override func awakeFromNib() {
                super.awakeFromNib()
                // Initialization code
            }
            @IBAction func changeCart(_ sender: Any) {
                let value = Int(stepper.value)
                quantityTextField.text = String(value)
                let x = Int(pricearr[0])
                priceLabel.text = String(x! * value)
            }
        }

您的代码有一个错误是，滚动tableView时，由于单元重用，该时间单元将重置为其默认值。

编辑：

达到目标的更好方法（据我了解）可以定义如下：

1. 删除步进动作

2. 从UITableview单元格类中删除操作

   class productTableViewCell：UITableViewCell {

     @IBOutlet var stepper: UIStepper! @IBOutlet var imageview: UIImageView! @IBOutlet var nameLabel: UILabel! @IBOutlet var priceLabel: UILabel! @IBOutlet var quantityTextField: UITextField! var price : String = "" override func awakeFromNib() { super.awakeFromNib() // Initialization code } } 

3，用下面的代码替换你的核心逻辑

@IBOutlet var tableDetails: UITableView!
    var CartArray : [[String: String]] = []
    var itemsArray : [[String: AnyObject]] = []
    let urlstring = "http://www.json-generator.com/api/json/get/ceghMiWudK?indent=2"
    var sum = 0

    override func viewDidLoad() {
        super.viewDidLoad()
        self.downloadJsonWithURL()
        tableDetails.delegate = self
        tableDetails.dataSource = self
        tableDetails.alwaysBounceVertical = false
        // Do any additional setup after loading the view.
    }
    func downloadJsonWithURL() {
        let url = NSURL(string: urlstring)
        URLSession.shared.dataTask(with: (url as? URL)!, completionHandler: {(data, response, error) -> Void in
            if let jsonObj = try? JSONSerialization.jsonObject(with: data!, options: .allowFragments) as? NSDictionary {
              //  print(jsonObj!.value(forKey: "Detail"))
                self.itemsArray = (jsonObj!.value(forKey: "Detail") as? [[String: AnyObject]])!

                OperationQueue.main.addOperation({
                    self.tableDetails.reloadData()
                })
            }
        }).resume()
    }

    func numberOfSections(in tableView: UITableView) -> Int {
        // #warning Incomplete implementation, return the number of sections
        return 1
    }
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int{
        if (section == 0){
            return itemsArray.count
        }else{
            return 1
        }
    }
    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {

        //if indexPath.section == 0{
            let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath) as! productTableViewCell
            let arr = itemsArray[indexPath.row]
            let urls = NSURL(string: arr["img"] as! String)
            let data = NSData (contentsOf: urls! as URL)
            cell.imageview.image = UIImage(data: data! as Data)
            cell.nameLabel.text = arr["productName"] as? String
            var price = arr["productPrice"] as! String

        var aQuntity : Float = 1
        let itemId : Int =  arr["sku"] as! Int

        for aDic in CartArray{
            if aDic["id"] == String(itemId){

            aQuntity = Float(String(aDic["quantity"]!))!
            }
        }


        cell.stepper.value = Double(Int(aQuntity))
        cell.stepper.tag = indexPath.row

        cell.stepper.addTarget(self, action: #selector(stapperValueChange), for:.valueChanged)
        price = price.replacingOccurrences(of: "KD", with: "")

            cell.priceLabel.text = String(Float(price)! * aQuntity)
        cell.quantityTextField.text = String(aQuntity)
            cell.price = price
            return cell
       // }
//        else if indexPath.section == 1{
//            let cell = tableView.dequeueReusableCell(withIdentifier: "couponcell", for: indexPath) as! CouponTableViewCell
//            return cell
//        }else {
//            let cell = tableView.dequeueReusableCell(withIdentifier: "checkout", for: indexPath) as! checkoutTableViewCell
//            return cell
//        }


    }

    func stapperValueChange (stepper : UIStepper){
        let index : Int = stepper.tag
        let arr = itemsArray[index]

        let cell : productTableViewCell = tableDetails.cellForRow(at: IndexPath(row: index, section: 0)) as! productTableViewCell

                let value = Float(stepper.value)
                cell.quantityTextField.text = String(value)
                let x = Float(cell.price)
                cell.priceLabel.text = String(Int(x! * value))
        let itemId : Int =  arr["sku"] as! Int

        var aFoundIndex : Int?
        var counter : Int = 0

        _ = CartArray.filter { (aDic) -> Bool in

            if aDic["id"] ==  String(itemId){
            aFoundIndex = counter
            }
            counter += 1
            return false
        }


        if(aFoundIndex != nil){
        CartArray.remove(at: aFoundIndex!)
        }

        CartArray.append(["quantity" : String(value),"id" : String(itemId)])
    }