如何正确分组和最小化 UITextfields 的样式代码？

Question

我正在尝试严格基于登录/注册字段来实现我的文本字段的标准通用样式。

所以，我将它们都设计为相同的，但我认为我正在重用大量可以压缩并可能在变量中使用的代码？我不知道该怎么做。

它的工作方式，但我确信它可以做得比这更好。我几乎可以肯定有一种方法可以最小化此代码以获得更好的实践。

我还在学习，所以我真的很想在开发中学习更好的实践。

这是我的注册视图和字段样式的示例：

class JoinVC: UIViewController, UITextFieldDelegate {`

    @IBOutlet weak var enterEmailTextField: UITextField!
    @IBOutlet weak var enterPasswordTextField: UITextField!
    @IBOutlet weak var enterNameTextField: UITextField!

    override func viewDidLoad() {
        super.viewDidLoad()

        // Field Border Corner + Width
        self.enterEmailTextField.layer.cornerRadius = 24.0
        self.enterEmailTextField.layer.borderWidth = 1.5
        self.enterPasswordTextField.layer.cornerRadius = 24.0
        self.enterPasswordTextField.layer.borderWidth = 1.5
        self.enterNameTextField.layer.cornerRadius = 24.0
        self.enterNameTextField.layer.borderWidth = 1.5
        // ...

        // Field Placeholder ColorEnter
        var placeholderEnterEmail = NSAttributedString(string: "Enter Email", attributes: [NSForegroundColorAttributeName : UIColor(red: 255/255, green: 255/255, blue:255/255, alpha: 0.6)])
        var placeholderEnterPass = NSAttributedString(string: "Choose Password", attributes: [NSForegroundColorAttributeName : UIColor(red: 255/255, green: 255/255, blue:255/255, alpha: 0.6)])
        var placeholderEnterName = NSAttributedString(string: "Choose Username", attributes: [NSForegroundColorAttributeName : UIColor(red: 255/255, green: 255/255, blue:255/255, alpha: 0.6)])

        enterEmailTextField.layer.sublayerTransform = CATransform3DMakeTranslation(20, 0, 0);
        enterPasswordTextField.layer.sublayerTransform = CATransform3DMakeTranslation(20, 0, 0);
        enterNameTextField.layer.sublayerTransform = CATransform3DMakeTranslation(20, 0, 0);
        // ...

        // Text Field Border color
        var borderColor : UIColor = UIColor( red: 255, green: 255, blue:255, alpha: 0.8 )
        self.enterPasswordTextField.layer.borderColor = borderColor.CGColor; enterEmailTextField.attributedPlaceholder = placeholderEnterEmail;
        self.enterEmailTextField.layer.borderColor = borderColor.CGColor; enterPasswordTextField.attributedPlaceholder = placeholderEnterPass;
        self.enterNameTextField.layer.borderColor = borderColor.CGColor; enterNameTextField.attributedPlaceholder = placeholderEnterName;
    // ...


    }
}

Answer 1

您可以使用Extension functionality。 只需创建一个 Extension 或 UITextField 并将您的代码放入该 Extension （简易教程here）

例如：

extension UITextField
{
    func setPlaceholderColorAndString(pholder: String, color: UIColor)
    {
        self.attributedPlaceholder = NSAttributedString(string:pholder,
            attributes:[NSForegroundColorAttributeName: color])
    }

    func setupField()
    {
        self.layer.cornerRadius = 24.0
        self.layer.borderWidth = 1.5
    }
}

然后在你的代码中你可以像这样使用它：

self.enterEmailTextField.setPlaceholderColorAndString(pholder: "Enter Email", color: UIColor(red: 255/255, green: 255/255, blue:255/255, alpha: 0.6)
self.enterEmailTextField.setupField()
self.enterPasswordTextField.setPlaceholderColorAndString(pholder: "Enter Password", color: UIColor(red: 255/255, green: 255/255, blue:255/255, alpha: 0.6)
self.enterPasswordTextField.setupField()

等等。当然上面的 sn-p 只是为了让你了解如何使用它，你可以改进它来满足你的需求。

Answer 2

可重用代码的简单解决方案是处理程序

  func setupTextField(textField : UITextField, placeHolderString: String)
  {
    let borderColor = UIColor( red: 1.0, green: 1.0, blue:1.0, alpha: 0.8 )
    textField.layer.cornerRadius = 24.0
    textField.layer.borderWidth = 1.5
    textField.layer.sublayerTransform = CATransform3DMakeTranslation(20, 0, 0);
    textField.layer.borderColor = borderColor.CGColor;
    textField.attributedPlaceholder = NSAttributedString(string: placeHolderString, attributes: [NSForegroundColorAttributeName : UIColor(red: 255/255, green: 255/255, blue:255/255, alpha: 0.6)])

  }

  override func viewDidLoad() {
    super.viewDidLoad()

    setupTextField(enterEmailTextField, placeHolderString: "Enter Email")
    setupTextField(enterPasswordTextField, placeHolderString: "Choose Password")
    setupTextField(enterNameTextField, placeHolderString: "Choose Username")
  }

注意：UIColor 值必须在 0.0 到 1.0 的范围内

Answer 3

我之前解决这个问题的方式，特别是如果项目中的所有文本字段都是：

1. 总是具有相同的属性，
2. 总是从情节提要中创建

是继承UITextField 并应用-awakeFromNib 中的属性：

class KBTextField: UITextField {
    let myAttributes = [NSForegroundColorAttributeName : UIColor(red: 255/255, green: 255/255, blue:255/255, alpha: 0.6)]
    let mySublayerTransform = CATransform3DMakeTranslation(20, 0, 0)
    let myBorderColor = UIColor( red: 255, green: 255, blue:255, alpha: 0.8 )

    override func awakeFromNib () {
        self.layer.sublayerTransform = mySublayerTransform
        self.layer.borderColor = myBorderColor.CGColor
        self.layer.cornerRadius = 24.0
        self.layer.borderWidth = 1.5
        self.attributedPlaceholder = NSAttributedString(string: self.placeholder!, attributes: myAttributes)
    }
}

然后您只需在故事板上设置类（在本例中为KBTextField），它会自动处理您的所有属性。

这样，您可以确保应用中的所有KBTextFields 看起来都相同，只要您通过情节提要创建它们。