有没有办法阻止 UICollectionView 重复使用单元格？

Question

我正在尝试在 Swift 4 中创建一个 table，其中包含 UITextFields 和 UILabel。

因为我在 UICollectionView 中有很多行，所以需要滚动。

但是，当我滚动时，重用功能弄乱了布局。

除了 UICollectionView，还有别的选择吗？在 Android 中，我创建了一个类似的应用程序，TableLayout 呈现所有单元格并且在滚动时不会导致任何错误。

所需布局

向下滚动然后再次向上滚动后的布局

我用这个方法复用：

    override func collectionView(_ collectionView: UICollectionView, 
                                 cellForItemAt indexPath: IndexPath) -> 
                                 UICollectionViewCell {

    let cell = collectionView.dequeueReusableCell(withReuseIdentifier: reuseIdentifier, for: indexPath) as! EUPCell

    cell.row = indexPath.section
    cell.column = indexPath.row
    //print("row: \(cell.row) column: \(cell.column)")
    CellCreation.make(self, indexPath, self.textfields, cell)

    return cell
}

static func make(_ view: EUPViewController,
                 _ indexPath: IndexPath,
                 _ textfields: TextFields,
                 _ cell: EUPCell) {

    let row = indexPath.section
    let column = indexPath.row

    if (row == 0 && column == 0) {
        CellCreation.makeLabel("Datum", cell)
    } else if (row == 0 && column == 1) {
        CellCreation.makeLabel("Skift", cell)
    } else if (row == 0 && column == 2) {
        CellCreation.makeLabel("EUP Operatör", cell)
    } else if (row == 0 && column == 3) {
        CellCreation.makeLabel("Kund", cell)
    } else if (row == 0 && column == 4) {
        CellCreation.makeLabel("Kontaktperson", cell)
    } else if (row == 0 && column == 5) {
        CellCreation.makeLabel("Artikel", cell)
    } else if (row == 0 && column == 6) {
        CellCreation.makeLabel("Plats", cell)
    } else if (row == 1 && (column >= 0 && column <= 6)) {
        CellCreation.makeInput(view, cell, textfields, false)
    } else if (row == 2 && column == 0) {
        CellCreation.makeLabel("Artikel nr", cell)
    } else if (row == 2 && column == 1) {
        CellCreation.makeLabel("Kolli nr", cell)
    } else if (row == 2 && column == 2) {
        CellCreation.makeLabel("FS nr", cell)
    } else if (row == 2 && column == 3) {
        CellCreation.makeLabel("Övrigt", cell)
    } else if (row == 2 && column == 4) {
        CellCreation.makeLabel("Antal i pall", cell)
    } else if (row == 2 && column == 5) {
        CellCreation.makeLabel("Antal OK", cell)
    } else if (row == 2 && column == 6) {
        CellCreation.makeLabel("Antal NOK", cell)
    } else if (row == 2 && column == 7) {
        CellCreation.makeLabel("Åtgärdade", cell)
    } else if (row == 2 && column == 8) {
        CellCreation.makeLabel("Utsorterade", cell)
    } else if ((row >= 3 && row <= 32) && (column >= 0 && column <= 8)) {
        columnCheck(view, column, cell, textfields)
    }
}

/**
 Uses a numeric keyboard for all UITextFields, except for those in
 the "Övrigt" column. This is equivalent to the fourth column
 of the table.
 */
static func columnCheck(_ view: EUPViewController,
                        _ column: Int,
                        _ cell: EUPCell,
                        _ textfields: TextFields) {

    if (column == 3) {
        CellCreation.makeInput(view, cell, textfields, false)
    } else {
        CellCreation.makeInput(view, cell, textfields, true)
    }
}

/**
 Creates an UILabel in the Cell. The font size
 is larger on an iPad.
 */
static func makeLabel(_ text: String, _ cell: EUPCell) {
    let label: UILabel
    let desiredFontSize: CGFloat

    label = UILabel(frame: CGRect(x: 0, y: 0, width: cell.frame.width, height: cell.frame.height))

    if (UIDevice.modelName.contains("iPhone")) {
        desiredFontSize = 8.0
    } else {
        desiredFontSize = 13.0
    }

    let font = UIFont(name: desiredFont, size: desiredFontSize)
    label.font = font

    label.textAlignment = .center

    label.text = text
    cell.addSubview(label)
}

/**
 Creates an UITextField in the given Cell.
 */
static func makeInput(_ view: EUPViewController,
                      _ cell: EUPCell,
                      _ textfields: TextFields,
                      _ isNumeric: Bool) {

    let textField = UITextField(frame: CGRect(x: 0, y: 0, width: cell.frame.width, height: cell.frame.height))

    let desiredFontSize: CGFloat

    if (UIDevice.modelName.contains("iPad")) {
        desiredFontSize = 14.0
    } else {
        desiredFontSize = 13.0
    }

    let font = UIFont(name: desiredFont, size: desiredFontSize)
    textField.font = font

    textField.delegate = view

    textField.borderStyle = .roundedRect
    textField.autocorrectionType = .no
    textField.textAlignment = .left

    textField.contentVerticalAlignment = .center

    if (isNumeric) {
        textField.keyboardType = .asciiCapableNumberPad
    } else {
        textField.keyboardType = UIKeyboardType.default
    }

    textfields.add(textField)

    cell.addSubview(textField)
}

Answer 1

为了避免这种混乱，您需要使用两种不同类型的电池。
1. 对于标签作为 header。
2. 将 TextField 作为输入。
现在你需要 return 2 in numberOfSectionsInCollectionView

现在在 sizeForItem 中设置单元格大小。确保为每个单元格添加了适当的条件。

在cellForItemAt,

if indexPath.section == 0  {
    if indexPath.row == 0  {
    // dequeue label Cell
    }
    // dequeue Textfield Cell            
}
else {
    if indexPath.row == 0  {
    // dequeue label Cell
    }
    // dequeue Textfield Cell    
}

注意：要正确管理文本字段的数据，您需要这样做 -> Swift UICollectionView Textfields

有没有办法阻止 UICollectionView 重复使用单元格？

Is there a way to stop UICollectionView from reusing cells?

tablelayout

ios

uicollectionview

uicollectionviewlayout

swift