         static var pushToCurrentVCFinished: Bool = false
         static var pushToNextVCFinished:Bool = false
         
+        static var navBarBackgroundImage: UIImage = UIImage()
+        
         static var navBarBarTintColor: UIColor = UIColor.defaultNavBarBarTintColor
         static var navBarBackgroundAlpha:CGFloat = 1.0
         static var navBarTintColor: UIColor = UIColor.defaultNavBarTintColor

        }
        set {
            objc_setAssociatedObject(self, &AssociatedKeys.pushToNextVCFinished, newValue, .OBJC_ASSOCIATION_ASSIGN)
        }
    }
    

    
    func wr_viewDidAppear(_ animated: Bool)
    {
        if let navBarBgImage = navBarBackgroundImage {
            navigationController?.setNeedsNavigationBarUpdate(backgroundImage: navBarBgImage)
        } else {
            navigationController?.setNeedsNavigationBarUpdate(barTintColor: navBarBarTintColor)
        }
        navigationController?.setNeedsNavigationBarUpdate(barBackgroundAlpha: navBarBackgroundAlpha)
        navigationController?.setNeedsNavigationBarUpdate(tintColor: navBarTintColor)
        navigationController?.setNeedsNavigationBarUpdate(titleColor: navBarTitleColor)
