如何在UISearchController中自定義searchBar？

Question

我知道如何為獨立的UISearchBar設置外觀，如下所示。

    let searchField = searchBar.value(forKey: "searchField") as? UITextField

    if let field = searchField {
        field.backgroundColor = UIColor.defaultBackgroundColor
        field.layer.cornerRadius = 15.0
        field.textColor = .white
        field.tintColor = .white

        field.font = UIFont.systemFont(ofSize: fl(13))
        field.layer.masksToBounds = true
        field.returnKeyType = .search
    }

但這不適用於UISearchController 。

我想將占位符的文本顏色和左放大鏡圖標設置為純白色。 （現在看來它們上面有彩色層）。

另外，輸入文字現在是黑色的，我也希望它是白色的。

總之，我想修改以下屬性。
1. textField背景顏色
2. textFiled占位符文本顏色
3. textFiled文字顏色
4. textFiled字體

誰知道怎么做？

在viewDidAppear中添加以下代碼：

            let placeholderString = NSAttributedString(string: "Placeholder", attributes: [NSAttributedStringKey.foregroundColor: UIColor.white])
            field.attributedPlaceholder = placeholderString

            let iconView = field.leftView as! UIImageView
            iconView.image = iconView.image?.withRenderingMode(.alwaysTemplate)
            iconView.tintColor = .white

Updata公司：
把這些設置放在ViewDidAppear()確實解決了我的一部分問題。
但是當我設置條形圖的背景顏色時， textfield's background color發生了變化。
因為searchBar.barTintColor = .red .red在導航項中嵌入的iOS11的UISearchController中不起作用，所以我使用了searchBar.backgroundColor = .red
這讓我很困惑。
那么如何分別改變searchBar的背景和textField的背景呢？

Answer 1

為搜索欄的文本字段設置attributedPlaceholder

@IBOutlet weak var sbSearchBar: UISearchBar!
if let textfield = sbSearchBar.value(forKey: "searchField") as? UITextField {

    textfield.backgroundColor = UIColor.red
    textfield.attributedPlaceholder = NSAttributedString(string: textfield.placeholder ?? "", attributes: [NSAttributedStringKey.foregroundColor : UIColor.white])

    if let leftView = textfield.leftView as? UIImageView {
        leftView.image = leftView.image?.withRenderingMode(.alwaysTemplate)
        leftView.tintColor = UIColor.white
    }

}

結果如下：

更新：

我想，這可能會對你有所幫助： 如何在searchcontroller中更改uitextfield顏色？

只需在此代碼中應用顏色組合即可。

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 = // Set text color
                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

}

結果：

Answer 2

在viewDidAppear中添加以下代碼：

            let placeholderString = NSAttributedString(string: "Placeholder", attributes: [NSAttributedStringKey.foregroundColor: UIColor.white])
            field.attributedPlaceholder = placeholderString

            let iconView = field.leftView as! UIImageView
            iconView.image = iconView.image?.withRenderingMode(.alwaysTemplate)
            iconView.tintColor = .white

更新 - 以下是自定義UISearchController顏色的完整代碼：

override func viewDidAppear(_ animated: Bool) {

    //sets navigationbar backgroundColor
    if let navigationbar = self.navigationController?.navigationBar {
        navigationbar.barTintColor = UIColor.magenta
    }

    let searchField = searchController.searchBar.value(forKey: "searchField") as? UITextField

    //sets searchBar backgroundColor
    searchController.searchBar.backgroundColor = .blue

    if let field = searchField {
        field.layer.cornerRadius = 15.0
        //sets text Color
        field.textColor = .brown

        //sets indicator and cancel button Color
        field.tintColor = .green

        field.font = UIFont.systemFont(ofSize: 13)
        field.layer.masksToBounds = true
        field.returnKeyType = .search

        //sets placeholder text Color
        let placeholderString = NSAttributedString(string: "placeholder", attributes: [NSAttributedStringKey.foregroundColor: UIColor.red])
        field.attributedPlaceholder = placeholderString

        //sets icon Color
        let iconView = field.leftView as! UIImageView
        iconView.image = iconView.image?.withRenderingMode(.alwaysTemplate)
        iconView.tintColor = .cyan

        //sets textField backgroundColor
        if let backgroundview = field.subviews.first {
            backgroundview.backgroundColor = UIColor.yellow
        }
    }
}