BaseViewControllerSample.swift

enum NavigationBarType {
    case closeOnRight
}

class BaseViewController: UIViewController {

    fileprivate static let barButtonSize = CGSize(width: 30, height: 30)
    
    fileprivate enum NavigationBarButtonType {
        case closeBtn
        
        func view(vc:BaseViewController)->UIBarButtonItem {
            switch self {
            case .closeBtn:
                let customView:UIView = UIView()
                customView.frame = CGRect(x: 0, y: 0, width: BaseViewController.barButtonSize.width, height: BaseViewController.barButtonSize.height)
                let image:UIImage = #imageLiteral(resourceName: "checkoutNavClose")
                let btn = UIButton(type: UIButtonType.custom)
                btn.frame = CGRect(x: 0, y: 0, width: customView.frame.size.width, height: customView.frame.size.height)
                btn.setImage(image, for: UIControlState.normal)
                btn.center = CGPoint(x: customView.frame.size.width / 2, y: customView.frame.size.height / 2 )
                btn.addTarget(vc, action: #selector(dismissViewController), for: UIControlEvents.touchUpInside)
                customView.addSubview(btn)
                return UIBarButtonItem(customView: customView)
            }
        }
    }
    
    override func viewDidLoad() {
        super.viewDidLoad()

        // Do any additional setup after loading the view.
        updateNavigationBar()
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

}

// Navigation Bar
extension BaseViewController {
    func updateNavigationBar() {
        switch self {
        case is CustomTransitionVCDetail: navigationBarWithCloseOnRight()
        default: break
        }
    }
    
    private func navigationBarWithCloseOnRight () {
        let btnItemRight = NavigationBarButtonType.closeBtn.view(vc: self)
        self.navigationItem.rightBarButtonItems = [btnItemRight]
    }
    
    
    
    
    
}

// Navigation Bar Button Blue Prints
extension BaseViewController {
    @objc func dismissViewController () {
        self.dismiss(animated: true, completion: nil)
    }
}