UILabel在UITableViewCell中使用自定义UIEdgeInsets截断

Question

我有一个UITableView与包含UILabel的单元格.UILabel有一个自定义的UIEdgeInset.我将UILabel子类化并设置UIEdgeInsets如下:

override func drawText(in rect: CGRect) {
    super.drawText(in: UIEdgeInsetsInsetRect(rect, insets))
}

override var intrinsicContentSize: CGSize {
    var contentSize = super.intrinsicContentSize
    contentSize.width += leftInset + rightInset
    contentSize.height += topInset + bottomInset
    return contentSize
}

但是当我在UILabel中有更多行时,标签有时会被截断.我已经将行高配置为UITableViewAutomaticDimension并设置了estimatedRowHeight.约束也很好.问题似乎是我正在设置UIEdgeInsets,因为如果我不自定义它可以正常工作.

可能我应该告诉单元格在设置insets后更新约束,但到目前为止我无法做到这一点.

故事板中添加的约束.Bottom,Top,Leading并且Trailing都与上海华盈(UITableViewCell中).所有常量都设置为0.

在cellForRowAtIndexPath代码中如下:

let cell = tableView.dequeueReusableCell(withIdentifier: "AnswersCell", for: indexPath) as! AnswerCell  
cell.answerLabel.text = alternatives[indexPath.row]
return cell

Answer 1

我像这样对标签进行了子类化：

class PaddingLabel: UILabel {

    var topInset: CGFloat = 0
    var bottomInset: CGFloat = 0
    var leftInset: CGFloat = 0
    var rightInset: CGFloat = 0

    override func drawText(in rect: CGRect) {
        let insets = UIEdgeInsets(top: topInset, left: leftInset, bottom: bottomInset, right: rightInset)
        super.drawText(in: UIEdgeInsetsInsetRect(rect, insets))
    }

    override var intrinsicContentSize: CGSize {
        get {
            var contentSize = super.intrinsicContentSize
            contentSize.height += topInset + bottomInset
            contentSize.width += leftInset + rightInset
            return contentSize
        }
    }
}

也许这就是get所缺少的。