I've disabled the share button on the navigation bar but it still shows up? about filebrowser HOT 3 CLOSED

class QLSPreviewController : QLPreviewController {
    override func viewDidLoad() {
        super.viewDidLoad()
    }
    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
    }
    override func viewDidAppear(_ animated: Bool) {
        super.viewDidAppear(true )
        //This hides the share item
        if let add =  self.childViewControllers.first as? UINavigationController {
            if let layoutContainerView  = add.view.subviews[1] as? UINavigationBar {
                 layoutContainerView.subviews[2].subviews[1].isHidden = true
            }
        }
    }
}