swift - 使用自动布局以编程方式设置 UITableViewCell 高度

Question

我想使用自动布局设置单元格高度，代码如下:

class AccountsBalanceResidueCell : BaseCell {

    private let title: UILabel = {
        let lbl = LabelSL.italicLarge()
        lbl.text = Strings.Common.accountsResidue.value
        return lbl
    }()

    private let amount: UILabel = LabelSL.italicLarge()

    func setup(_ amount: String) {
        self.amount.text = amount + " " + Strings.Common.roubleSymbol.value
    }

    override func prepare() {
        contentView.backgroundColor = .cyan
        contentView.translatesAutoresizingMaskIntoConstraints = false
        addSubview(title)
        addSubview(amount)
        setConstraints()
    }

    private func setConstraints(){
        let height: CGFloat = UIScreen.main.bounds.size.height * 0.3333

        contentView.heightAnchor.constraint(equalToConstant: height).isActive = true
    }
}

但是，我在日志中收到错误:

Unable to simultaneously satisfy constraints. Probably at least one of the constraints in the following list is one you don't want. Try this: (1) look at each constraint and try to figure out which you don't expect; (2) find the code that added the unwanted constraint or constraints and fix it. ( " (active)>", " (active)>" )

Will attempt to recover by breaking constraint (active)>

Answer 1

通过添加辅助 View 解决了这个问题:

private let container: UIView = {
    let view = UIView()
    view.translatesAutoresizingMaskIntoConstraints = false
    view.backgroundColor = .clear
    return view
  }()

container.topAnchor.constraint(equalTo: contentView.topAnchor).isActive = true
    container.leftAnchor.constraint(equalTo: contentView.leftAnchor).isActive = true
    container.rightAnchor.constraint(equalTo: contentView.rightAnchor).isActive = true
    container.bottomAnchor.constraint(equalTo: contentView.bottomAnchor).isActive = true
    let heightConstraint = container.heightAnchor.constraint(equalToConstant: height)
    heightConstraint.priority = UILayoutPriority(rawValue: 751)
    heightConstraint.isActive = true