UISearchController iOS 11 Customization

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.