ios - UITextField 标准样式以编程方式

Question

当我使用 Storyboard创建一个 UITextField 时，它看起来像下图。但是，当我以编程方式创建 UITextField 时，它完全没有样式。我知道我可以将自定义样式应用到文本字段，但是在以编程方式创建文本字段时是否有一种简单的方法来获取此标准样式？

Answer 1

像这样:

let t = UITextField()
t.frame = CGRect(x: 10, y: 20, width: self.view.frame.width - 20, height: 40)
t.layer.cornerRadius = 5
t.layer.borderColor = UIColor.lightGray.cgColor
t.layer.borderWidth = 1
t.leftView = UIView(frame: CGRect(x: 0, y: 0, width: 10, height: t.frame.height))
t.leftViewMode = .always
t.rightView = UIView(frame: CGRect(x: 0, y: 0, width: 10, height: t.frame.height))
t.rightViewMode = .always
t.clearButtonMode = .whileEditing
self.view.addSubview(t)

编辑:

在某处添加此类，以便于/全局访问它。

class StyledTextField: UITextField { 
    override init(frame: CGRect) {
        super.init(frame: frame)
        self.layer.cornerRadius = 5
        self.layer.borderColor = UIColor.lightGray.cgColor
        self.layer.borderWidth = 1
        self.leftView = UIView(frame: CGRect(x: 0, y: 0, width: 10, height: t.frame.height))
        self.leftViewMode = .always
        self.rightView = UIView(frame: CGRect(x: 0, y: 0, width: 10, height: t.frame.height))
        self.rightViewMode = .always
        self.clearButtonMode = .whileEditing
    }
}

然后你可以从任何你想要的地方调用这个UITextField

let t = StyledTextField()
t.frame = CGRect(x: 10, y: 20, width: self.view.frame.width - 20, height: 40)
self.view.addSubview(t)

编辑 2:

使用 UIEdgeInsets 在所有四个边上填充。

class StyledTextField: UITextField { 
    let insetConstant = UIEdgeInsets(top: 4, left: 10, bottom: 4, right: 10)

    override func textRect(forBounds bounds: CGRect) -> CGRect {
        return UIEdgeInsetsInsetRect(bounds, insetConstant)
    }

    override func editingRect(forBounds bounds: CGRect) -> CGRect {
        return UIEdgeInsetsInsetRect(bounds, insetConstant)
    }

    override func placeholderRect(forBounds bounds: CGRect) -> CGRect {
        return UIEdgeInsetsInsetRect(bounds, insetConstant)
    }

    override init(frame: CGRect) {
        super.init(frame: frame)

        self.layer.cornerRadius = 5
        self.layer.borderColor = UIColor(white: 2/3, alpha: 0.5).cgColor
        self.layer.borderWidth = 1
        self.clearButtonMode = .whileEditing
        self.keyboardType = UIKeyboardType.decimalPad
    }

    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
}