Ios UIPickerView没有'；t在视图中更改颜色将显示if语句

我正在制作一个应用程序，其中我有4个选项卡，最后一个选项卡用于更改为暗模式（更改标签颜色、背景颜色、键盘颜色和pickerView颜色）。func是我改变颜色的地方。除了pickerView没有改变颜色，其他一切都正常，这就是我需要帮助的地方

override func viewWillAppear(_ animated: Bool) {

    if UserDefaults.standard.integer(forKey: "dark") == 1{

        self.view.backgroundColor = UIColor.darkGray
        UITextField.appearance().keyboardAppearance = .dark
        textField.backgroundColor = UIColor.white
        textField.textColor = UIColor.black
        textField2.textColor = UIColor.black
        textField2.backgroundColor = UIColor.white
        label.textColor = UIColor.white
        label.textColor = UIColor.white
        labelIN1.textColor = UIColor.white

        func pickerView(_ pickerView: UIPickerView, attributedTitleForRow row: Int, forComponent component: Int) -> NSAttributedString? {
            let titleData = list[row]
            let myTitle = NSAttributedString(string: titleData, attributes: [NSForegroundColorAttributeName:UIColor.black])
            return myTitle
        }


    }else{

        self.view.backgroundColor = UIColor.white
        UITextField.appearance().keyboardAppearance = .light
        textField.backgroundColor = UIColor.white
        textField.textColor = UIColor.black
        textField2.textColor = UIColor.black
        textField2.backgroundColor = UIColor.white
        label.textColor = UIColor.black
        label.textColor = UIColor.black
        labelIN1.textColor = UIColor.black

        func pickerView(_ pickerView: UIPickerView, attributedTitleForRow row: Int, forComponent component: Int) -> NSAttributedString? {
            let titleData = list[row]
            let myTitle = NSAttributedString(string: titleData, attributes: [NSForegroundColorAttributeName:UIColor.white])
            return myTitle
        }

    }

}

---

代码段中的问题是，委托在

视图中声明为嵌套函数时将出现
，如果其作用域如下所示，则应将其清除：

override func viewWillAppear(_ animated: Bool) {

        if UserDefaults.standard.integer(forKey: "dark") == 1{

            self.view.backgroundColor = UIColor.darkGray
            UITextField.appearance().keyboardAppearance = .dark
            textField.backgroundColor = UIColor.white
            textField.textColor = UIColor.black
            textField2.textColor = UIColor.black
            textField2.backgroundColor = UIColor.white
            label.textColor = UIColor.white
            label.textColor = UIColor.white
            labelIN1.textColor = UIColor.white

        }else{

            self.view.backgroundColor = UIColor.white
            UITextField.appearance().keyboardAppearance = .light
            textField.backgroundColor = UIColor.white
            textField.textColor = UIColor.black
            textField2.textColor = UIColor.black
            textField2.backgroundColor = UIColor.white
            label.textColor = UIColor.black
            label.textColor = UIColor.black
            labelIN1.textColor = UIColor.black

        }
    }

    func pickerView(_ pickerView: UIPickerView, attributedTitleForRow row: Int, forComponent component: Int) -> NSAttributedString? {

        let titleData = list[row]

        if UserDefaults.standard.integer(forKey: "dark") == 1{

            let myTitle = NSAttributedString(string: titleData, attributes: [NSForegroundColorAttributeName:UIColor.white])
            return myTitle

        } else {

            let myTitle = NSAttributedString(string: titleData, attributes: [NSForegroundColorAttributeName:UIColor.black])
            return myTitle
        }
    }

同时，确保实施：


class ViewController:UIViewController，UIPickerViewDelegate{/*…*/}
pickerView.delegete=self

在代码的某个地方

有关详细信息，您可能需要查看。
欢迎使用SO。关于你的问题，你能更具体一点吗？你会遇到什么错误，什么不起作用？picker视图颜色更改现在起作用，但只有在我开始使用pickerView时才起作用。viewWillApear中func的原因是我需要它在我使用黑暗模式swift（黑暗）时立即切换，就像所有其他标签和按钮一样。