swift - 如何将 View TableViewCell 转换为 UIGestureView

Question

我试图在手势 View 点击时更改我的表格 View 单元格内容，但是我收到了错误

线程1:信号SIGABRT

无法将“UILabel”类型的值 (0x117f4ad68) 转换为“MyApplication.Read”

func ReadAnswer(_ sender: UIGestureRecognizer)  {
    let CellIndex = sender.view?.tag
    print(CellIndex!)
    let test = sender.view as! Read!  // This produces error

    test?.comment.text = "You have clicked on cell \(CellIndex)"
}

func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
    let mycell = tableView.dequeueReusableCell(withIdentifier: "Read", for: indexPath) as! Read

    mycell.comment.tag = indexPath.row
    mycell.comment.text = streamsModel.Posts[indexPath.row]

    let Gesture = UITapGestureRecognizer(target: self, action: #selector(ReadAnswer(_:)))
    Gesture.delegate = self as? UIGestureRecognizerDelegate

    mycell.comment.addGestureRecognizer(Gesture)

    return cell
}

再次在标签上单击我想更改该标签的内容，以说明您已单击单元格 (CellIndex)。我可以在每次点击时获得正确的索引，但是在 Let Test 上它给出了一个错误。

Answer 1

您已将 Gesture 添加到 UILabel..!! comment 是 UILabel。

let Gesture = UITapGestureRecognizer(target: self, action: #selector(ReadAnswer(_:)))
Gesture.delegate = self as? UIGestureRecognizerDelegate

mycell.comment.addGestureRecognizer(Gesture)

在Gesture Action中，sender.view应该是UILabel。所以出现了下面的错误。

无法将“UILabel”类型的值 (0x117f4ad68) 转换为“MyApplication.Read”

func ReadAnswer(_ sender: UIGestureRecognizer)  {
    let CellIndex = sender.view?.tag
    print(CellIndex!)


    let test = sender.view as! Read!  // This produces error

    test?.comment.text = "You have clicked on cell \(CellIndex)"

}

求解

我们必须为此使用字典。所以，我们可以避免 tableView 的重用。你可以拿到我的answer对于 UIStepper。同样的逻辑如下。

var textDict = [Int : String]()
override func viewDidLoad() {
    super.viewDidLoad()

    for i in 0..<70 // numberOfRows
    {
        textDict[i] = "Hello"
    }
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {

    return 70
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {

    let cell = tableView.dequeueReusableCell(withIdentifier: "table", for: indexPath) as! TblTableViewCell

    let Gesture = UITapGestureRecognizer(target: self, action: #selector(ReadAnswer))
    Gesture.delegate = self as? UIGestureRecognizerDelegate

    cell.commentLbl.tag = indexPath.row
    cell.commentLbl.isUserInteractionEnabled = true
    cell.commentLbl.addGestureRecognizer(Gesture)

    cell.commentLbl.text = textDict[indexPath.row]

    return cell
}

func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {

    return 50
}

@objc func ReadAnswer(_ sender: UIGestureRecognizer)  {

    let CellIndex : Int = (sender.view?.tag)!

    textDict[CellIndex] = "You have clicked on cell \(CellIndex)"

    tblView.reloadData()

}