Quick access to cancel button in UISearchController

UISearchControllerCancelButton.swift

/**
    Example for customize your cancel button:

        let controller = UISearchController(searchResultsController: nil)
        controller.searchBar.showsCancelButton = true
        
        if let button = controller.cancelButton() {
            // Customize button
            let iconImage = UIImage(named: "icon")
            button.isEnabled = true
            button.setTitle("", for: .normal)
            button.setBackgroundImage(iconImage, for: .normal)
            button.addTarget(self, action: #selector(tap), for: .touchUpInside)
        }
*/

extension UISearchController {
    func cancelButton() -> UIButton? {
        if #available(iOS 13.0, *) {
            return findCancelButton13()
        }
        return findCancelButtonOld()
    }
    
    func findCancelButtonOld() -> UIButton? {
        for subView in searchBar.subviews {
            for v in subView.subviews {
                if let button = v as? UIButton {
                    return button
                }
            }
        }
        return nil
    }
    
    @available(iOS 13.0, *)
    func findCancelButton13() -> UIButton? {
        for subView in searchBar.subviews {
            for v in subView.subviews {
                for b in v.subviews {
                    if let button = b as? UIButton {
                        return button
                    }
                }
            }
        }
        return nil
    }
}