iOS UILabel 利用编辑菜单实现内容拷贝

项目中遇到需要拷贝文本链接的需求，相当然是通过继承子类化实现， 灵光一闪通过扩展最终完美实现，效果如下：

Simulator Screen Shot - iPhone 6s Plus - 2020-05-28 at 14.53.48.png

使用：
    lazy var label: UILabel = {
        let view = UILabel(frame: .zero)
        view.addLongPressMenuItems()
//        UIMenuController.shared.menuItems = menuItems
        view.text = "这是一调测试信息"
        
        view.backgroundColor = UIColor.background
        return view
    }()

//扩展实现
@objc public extension UILabel{
        
    func addLongPressMenuItems() {
        isUserInteractionEnabled = true

        let recognizer = UILongPressGestureRecognizer(target: self, action: #selector(handleMenuItems(_:)));
        addGestureRecognizer(recognizer)
    }
    
    // MARK: -funtions
    @objc func handleMenuItems(_ recognizer: UIGestureRecognizer) {
        guard let recognizerView = recognizer.view,
              let recognizerSuperView = recognizerView.superview
          else { return }
   
        if #available(iOS 13.0, *) {
            UIMenuController.shared.showMenu(from: recognizerSuperView, rect: recognizerView.frame)

        } else {
            UIMenuController.shared.setTargetRect(recognizerView.frame, in: recognizerSuperView)
            UIMenuController.shared.setMenuVisible(true, animated: true)
        }
        recognizerView.becomeFirstResponder()
    }
    
    // MARK: -edit menu
    override var canBecomeFirstResponder: Bool {
        return true
    }
    
    override func canPerformAction(_ action: Selector, withSender sender: Any?) -> Bool {
        guard let menuItems = UIMenuController.shared.menuItems else { return [#selector(copy(_:))].contains(action)}
        let actions: [Selector] = menuItems.map { $0.action }
        return actions.contains(action)
    }
    
    // MARK: - UIResponderStandardEditActions
    override func copy(_ sender: Any?) {
        UIPasteboard.general.string = text
    }
    
    override func paste(_ sender: Any?) {
        text = UIPasteboard.general.string
    }
    
    override func delete(_ sender: Any?) {
        text = ""
    }
}