swift - 导航控制器。背景颜色

Question

对于一个控制器，我有设置：

self.navigationController?.navigationBar.setBackgroundImage(UIImage(), for: .default)
self.navigationController?.navigationBar.shadowImage = UIImage()

和

override func scrollViewDidScroll(_ scrollView: UIScrollView) {
        var offset = scrollView.contentOffset.y / 150
        if offset > 1 {
            offset = 1
            self.navigationController?.navigationBar.backgroundColor = UIColor(red: 82/255, green: 76/255, blue: 70/255, alpha: offset)
            UIApplication.shared.statusBarView?.backgroundColor = UIColor(red: 82/255, green: 76/255, blue: 70/255, alpha: offset)
            self.navigationItem.title = name
        } else {
            self.navigationController?.navigationBar.backgroundColor = UIColor(red: 82/255, green: 76/255, blue: 70/255, alpha: offset)
             UIApplication.shared.statusBarView?.backgroundColor = UIColor(red: 82/255, green: 76/255, blue: 70/255, alpha: offset)
            self.navigationItem.title = ""
        }
    }

主要问题是当我按下后退按钮时，设置保存。最后我有白色的 NavigationController。如何使设置不取自最后一个控制器？

func makeSearchController() {
        searchController = UISearchController(searchResultsController: nil)
        navigationItem.searchController = searchController
        navigationItem.hidesSearchBarWhenScrolling = false
        searchController.searchResultsUpdater = self
        searchController.dimsBackgroundDuringPresentation = false
        searchController.searchBar.tintColor = .white
        searchController.searchBar.placeholder = "Блюдо или продукт ..."
    }

Answer 1

您可以在 中重置导航控制器的颜色viewWillDisappear，如下所示：

override func viewWillDisappear(_ animated: Bool) {
    super.viewWillDisappear(animated)
    self.navigationController?.navigationBar.backgroundColor = UIColor(red: 221/255, green: 221/255, blue: 225/255, alpha: offset) //gray color
    UIApplication.shared.statusBarView?.backgroundColor = UIColor(red: 221/255, green: 221/255, blue: 225/255, alpha: offset) //gray color
}