iOS: Underline textfield or label

func addUnderline(toTextField textField: DefaultTextField) {
        textField.borderStyle = UITextBorderStyle.none;
        let border = CALayer()
        let borderWidth = CGFloat(1.0)
        border.borderColor = UIColor(red: 91/255.0, green: 92/255.0, blue: 93/255.0, alpha: 1).cgColor
        border.frame = CGRect(x: 0, y: textField.frame.size.height - borderWidth, width: textField.frame.size.width, height: textField.frame.size.height)
        border.borderWidth = borderWidth
        textField.layer.addSublayer(border)
        textField.layer.masksToBounds = true
    }

iOS: Constants / Enums

enum StringEnum: String
{
  case one = "one"
  case two = "two"
  case three = "three"
}

let anEnum = StringEnum(rawValue: "one")!

print("anEnum = \"\(anEnum.rawValue)\"")

iOS: Add views to stackview programmatically

let title = DefaultLabel()
        title.text = "Date Available"
        title.textAlignment = NSTextAlignment.left
        view.containerStackView.insertArrangedSubview(title, at: 14)
        title.leadingAnchor.constraint(equalTo: view.containerStackView.layoutMarginsGuide.leadingAnchor, constant: 16).isActive = true
        title.trailingAnchor.constraint(equalTo: view.containerStackView.layoutMarginsGuide.trailingAnchor, constant: -16).isActive = true