UISearchController iOS 11 Customization

I had been using the following code prior to iOS 11 to customize the appearance of the UISearchController search bar:

var searchController = UISearchController(searchResultsController: nil)
searchController.searchBar.setDefaultSearchBar()
searchController.searchResultsUpdater = self

if #available(iOS 11.0, *) {
    navigationItem.searchController = searchController
} else {
    tableView.tableHeaderView = searchController.searchBar
}

extension UISearchBar {
    func setDefaultSearchBar() {
        self.tintColor = UIColor.blue
        self.searchBarStyle = .minimal
        self.backgroundImage = UIImage(color: UIColor.clear)
        let searchBarTextField = self.value(forKey: "searchField") as! UITextField
        searchBarTextField.textColor = UIColor.white
        searchBarTextField.tintColor = UIColor.blue
        searchBarTextField = .dark
    }
}

However, the appearance of the search bar fails to update when running the same code on iOS 11.

iOS 10:

iOS 11:

Much of the attention to this question so far has focused on the text color of the search bar. I am looking at more than this - the background color, tint color, the search indicator, clear button color, etc.

I just found out how to set them: (with some help of Brandon and Krunal, thanks!)

The "Cancel" text:

searchController.searchBar.tintColor = .white

The search icon:

searchController.searchBar.setImage(UIImage(named: "my_search_icon"), for: UISearchBarIcon.search, state: .normal)

The clear icon:

searchController.searchBar.setImage(UIImage(named: "my_search_icon"), for: UISearchBarIcon.clear, state: .normal)

The search text:

UITextField.appearance(whenContainedInInstancesOf: [UISearchBar.self]).defaultTextAttributes = [NSAttributedStringKey.foregroundColor.rawValue: UIColor.white]

The placeholder:

UITextField.appearance(whenContainedInInstancesOf: [UISearchBar.self]).attributedPlaceholder = NSAttributedString(string: "placeholder", attributes: [NSAttributedStringKey.foregroundColor: UIColor.white])

The white background:

if #available(iOS 11.0, *) {
    let sc = UISearchController(searchResultsController: nil)
    sc.delegate = self
    let scb = sc.searchBar
    scb.tintColor = UIColor.white
    scb.barTintColor = UIColor.white

    if let textfield = scb.value(forKey: "searchField") as? UITextField {
        textfield.textColor = UIColor.blue
        if let backgroundview = textfield.subviews.first {

            // Background color
            backgroundview.backgroundColor = UIColor.white

            // Rounded corner
            backgroundview.layer.cornerRadius = 10;
            backgroundview.clipsToBounds = true;
        }
    }

    if let navigationbar = self.navigationController?.navigationBar {
        navigationbar.barTintColor = UIColor.blue
    }
    navigationItem.searchController = sc
    navigationItem.hidesSearchBarWhenScrolling = false
}

Taken from here.

To properly set the text typed into the search bar to white use (when using a dark field color):

searchController.searchBar.barStyle = .black

To set the textfield background color

if #available(iOS 11.0, *) {

        if let textfield = searchController.searchBar.value(forKey: "searchField") as? UITextField {
            if let backgroundview = textfield.subviews.first {

                // Background color
                backgroundview.backgroundColor = UIColor.white

                // Rounded corner
                backgroundview.layer.cornerRadius = 10;
                backgroundview.clipsToBounds = true;
            }
        }
    }

However using something like

textfield.textColor = UIColor.blue

in the above does not seem to work.