ios TableviewCell重新计算高度

Question

我有一个tabviewcell，我想动态设置标签文本（tableviewcell的子视图）。但是当我设置标签文本时，heigh显示为0（在屏幕上看不到）。我的代码在下面，但是当我设置文本时，它没有重新计算高度。这是什么问题？

protocol EarningsSemisecureViewDelegate : class {
    func enterButtonTapped()
}

class EarningsSemisecureViewCell : UITableViewCell {

    var noDataText : String? {
        didSet(newValue) {
            noDataLabel.text = newValue?.localized()
        }
    }
    private var noDataLabel = RadxLabel()
    weak var delegate: EarningsSemisecureViewDelegate?

    override init(style: UITableViewCell.CellStyle, reuseIdentifier: String?) {
        super.init(style: style, reuseIdentifier: reuseIdentifier)
        customizeView()
     }

    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
        customizeView()
    }

    private func customizeView() {
        self.backgroundColor = UIColor.white
        self.contentView.backgroundColor = UIColor.white
        selectionStyle = UITableViewCell.SelectionStyle.none
        noDataLabel.numberOfLines = 0
        noDataLabel.textAlignment = .center
        noDataLabel.translatesAutoresizingMaskIntoConstraints = false
        self.contentView.addSubview(noDataLabel)
        noDataLabel.leading = self.contentView.leading + 10
        noDataLabel.trailing = self.contentView.trailing - 10
        noDataLabel.top = self.contentView.top + 20

        let button = WalletButton()
        button.setTitle("login.button.enter".localized(), for: .normal)
        button.styleNo = 1
        button.translatesAutoresizingMaskIntoConstraints = false
        button.addTapGestureRecognizer {[weak self] in
        if let semiSecureViewDelegate = self?.delegate {
            semiSecureViewDelegate.enterButtonTapped()
        }
    }
    self.contentView.addSubview(button)
    button.top = noDataLabel.bottom + 30
    button.trailing = self.contentView.trailing - 10
    button.leading = self.contentView.leading + 10
    }
}



let semisecureViewCell = EarningsSemisecureViewCell()
        semisecureViewCell.noDataText = "earnings.not.login.info"
        return semisecureViewCell

单元格在tableviewdatasource中返回。