swift - UICollectionView CellForItemAt 在滚动时被多次调用导致单元格文本重叠

Question

我有一个显示日期数组的 Collection View 。当 View 首次加载时，单元格看起来很好，但在我水平滚动一点后，似乎每次都会触发 CellForItemAt 方法，而不是一次，导致单元格的文本与其默认值重叠。我在下面发布了一些屏幕截图:

最初，所有 View 的显示方式和外观:

稍微滚动后:

多次滚动后:

这是我的 CellForItemAt 代码(由于反复试验，它非常困惑):

func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
    let dateCell = calenderView.dequeueReusableCell(withReuseIdentifier: "dateCell", for: indexPath)
    dateCell.layer.cornerRadius = 7
    let dayLabel = UILabel(frame: CGRect(x: 0, y: 0, width: dateCell.frame.width, height: dateCell.frame.height / 2))
    dayLabel.text = "\(Calendar.current.dateComponents([.day], from: dates[indexPath.row]).day!)"
    let weekdayLabel = UILabel(frame: CGRect(x: 0, y: dateCell.frame.height / 2, width: dateCell.frame.width, height: dateCell.frame.height / 2))
    let formatter = DateFormatter()
    formatter.dateFormat = DateFormatter.dateFormat(fromTemplate: "EEE", options: 0, locale: NSLocale.current)
    weekdayLabel.text = formatter.string(from: dates[indexPath.row])
    dayLabel.text = "\(Calendar.current.dateComponents([.day], from: dates[indexPath.row]).day!)"
    weekdayLabel.textAlignment = .center
    weekdayLabel.font = weekdayLabel.font.withSize(10)
    dayLabel.textAlignment = .center
    dateCell.addSubview(dayLabel)
    dateCell.addSubview(weekdayLabel)
    return dateCell
}

Answer 1

因为cell resuing，不要在cellForRow中添加 subview

dateCell.addSubview(dayLabel)
dateCell.addSubview(weekdayLabel)

//

在 cellForRowAt

if indexPath.row == indexOfGray {
  //  gray color
}
else {
{
  // default color 
}

设计将在 xib 中，或者在 init 方法中自定义单元格类