UIButton that resizes to fit its titleLabel

Question

I have a UIButton that I add to my view controller\'s view in a storyboard. I add centering constraints to position it and leading space constraints to limit it

Answer 1

class SFResizableButton: UIButton {
  override var intrinsicContentSize: CGSize {
    get {
      var labelSize = CGSize.zero
        if let text = titleLabel?.text, let font = titleLabel?.font {
          labelSize.width = text.width(constrained: .greatestFiniteMagnitude, font: font)
        } else if let att = titleLabel?.attributedText {
          labelSize.width = att.width(constrained: .greatestFiniteMagnitude)
        }
      if let imageView = imageView {
        labelSize.width = labelSize.width + imageView.frame.width
      }
      let desiredButtonSize = CGSize(width: ceil(labelSize.width) + titleEdgeInsets.left + titleEdgeInsets.right + imageEdgeInsets.left + imageEdgeInsets.right, height: labelSize.height + titleEdgeInsets.top + titleEdgeInsets.bottom + imageEdgeInsets.top + imageEdgeInsets.bottom)

        return desiredButtonSize
    }
  }
}
extesion String {
  func width(constrained height: CGFloat, font: UIFont) -> CGFloat {
    let constraintRect = CGSize(width: .greatestFiniteMagnitude, height: height)
      let boundingBox = (self as NSString).boundingRect(with: constraintRect, options: .usesLineFragmentOrigin, attributes: [NSFontAttributeName: font], context: nil)

      return boundingBox.width
  }
}

extension NSAttributedString {
  func width(constrained height: CGFloat) -> CGFloat {
    let constraintRect = CGSize(width: .greatestFiniteMagnitude, height: height)
      let boundingBox = boundingRect(with: constraintRect, options: .usesLineFragmentOrigin, context: nil)

      return boundingBox.width
  }
}