Swift-SearchController'；的导航项不在顶部

在将searchcontroller添加到自定义导航栏时，我面临以下问题

2020-05-20 19:53:18.669036+0530 DiffableTableView[27679:1184112][Assert]惊喜！激活导航项不在堆栈顶部的搜索控制器。这个病例需要在UIKit中检查。项目=（空）， 搜索宿主项=title='Guest'隐藏BackButton rightBarButtonItems=0x600000bfccd0 searchController=0x7fade707e800隐藏ArchBar滚动时 2020-05-20 19:53:18.669211+0530 DiffableTableView[27679:1184112][Assert]导航栏承载的搜索栏的意外代码路径。这是一个UIKit问题

let customNavigationItem: UINavigationItem = {
    let navigationItem = UINavigationItem()
    navigationItem.title = "Invite Guest"
    navigationItem.setRightBarButton(UIBarButtonItem(barButtonSystemItem: .close, target: self, action: #selector(closeButtonPressed)), animated: true)
    navigationItem.hidesBackButton = true
    return navigationItem
  }()

lazy var navigationBar: UINavigationBar = {
    let navigationBar = UINavigationBar()
    navigationBar.isTranslucent = false
    navigationBar.items = [customNavigationItem]
    navigationBar.sizeToFit()
    navigationBar.translatesAutoresizingMaskIntoConstraints = false
    return navigationBar
  }()

    let searchController = UISearchController(searchResultsController: nil)
    searchController.hidesNavigationBarDuringPresentation = false
    searchController.obscuresBackgroundDuringPresentation = false
    customNavigationItem.searchController = searchController