UIActivityViewController share message cancel not showing

Question

When I want to share a URL with the message application via the UIActivityViewController. The cancel button is white (I guess because it still tappable)

It only appears on iOS 11, here the code use to present the UIActivityViewController and I already tried to change the color before presenting the UIActivityViewController but the button stay white :

if #available(iOS 11.0, *) {
   UIButton.appearance(whenContainedInInstancesOf:[UINavigationController.self]).tintColor = .blue
}

Here the code used to present the UIActivityViewController

let vc = UIActivityViewController(activityItems: [article.webReference], applicationActivities: [])
        self.present(vc, animated: false, completion:nil)

        vc.completionWithItemsHandler = {(s, ok, items, error) in
            switch s {
            case UIActivityType.mail?:
                print("mail")
                AnalyticsHelper.sharedInstance.sendShareMailEvent(articleUrl: article.webReference)
            case UIActivityType.postToFacebook?:
                print("facebook")
                AnalyticsHelper.sharedInstance.sendShareFacebookEvent(articleUrl: article.webReference)
            case UIActivityType.postToTwitter?:
                print("twitter")
                AnalyticsHelper.sharedInstance.sendShareTwitterEvent(articleUrl: article.webReference)
            default:
                print("others")
            }
        }

Answer 1

I had a same problem because of UIBarButtomItem.apperance().tintColor changed. Instead of changing default UI look I created my class of NavigationController which inherits from UINavigationController and in viewDidLoad method I have customise what I need. Next I changed all UInavigationController uses in storyboard and pure code to NavigationController. And now I can change controls for this class in AppDelegate, for example:

let navBarButton = UIBarButtonItem.appearance(whenContainedInInstancesOf: [NavigationController.self])
navBarButton.tintColor = .white