添加带属性的占位符:

let attributes : [String : Any]  = [ NSForegroundColorAttributeName: UIColor.lightGray,
                                     NSFontAttributeName : UIFont(name: "Helvetica Neue Light Italic", size: 12.0)!
                                   ]
x_textfield.attributedPlaceholder = NSAttributedString(string: "Placeholder Text", attributes:attributes)

Swift 3(可能是2)，你可以覆盖didSet占位符在UITextField子类上应用属性，这样:

override var placeholder: String? {

    didSet {
        guard let tmpText = placeholder else {
            self.attributedPlaceholder = NSAttributedString(string: "")
            return
        }

        let textRange = NSMakeRange(0, tmpText.characters.count)
        let attributedText = NSMutableAttributedString(string: tmpText)
        attributedText.addAttribute(NSForegroundColorAttributeName , value:UIColor(white:147.0/255.0, alpha:1.0), range: textRange)

        self.attributedPlaceholder = attributedText
    }
}

在我的例子中，我使用Swift 4

我为UITextField创建扩展

extension UITextField {
    func placeholderColor(color: UIColor) {
        let attributeString = [
            NSAttributedStringKey.foregroundColor: color.withAlphaComponent(0.6),
            NSAttributedStringKey.font: self.font!
            ] as [NSAttributedStringKey : Any]
        self.attributedPlaceholder = NSAttributedString(string: self.placeholder!, attributes: attributeString)
    }
}

yourField。placeholderColor(颜色:UIColor.white)

像这样创建UITextField扩展:

extension UITextField{
   @IBInspectable var placeHolderColor: UIColor? {
        get {
            return self.placeHolderColor
        }
        set {
            self.attributedPlaceholder = NSAttributedString(string:self.placeholder != nil ? self.placeholder! : "", attributes:[NSAttributedString.Key.foregroundColor: newValue!])
        }
    }
}

在你的故事板或。xib中。你会看到

我很惊讶这里有这么多糟糕的解决方案。

这里有一个永远有效的版本。

斯威夫特4.2

extension UITextField{
    @IBInspectable var placeholderColor: UIColor {
        get {
            return self.attributedPlaceholder?.attribute(.foregroundColor, at: 0, effectiveRange: nil) as? UIColor ?? .lightText
        }
        set {
            self.attributedPlaceholder = NSAttributedString(string: self.placeholder ?? "", attributes: [.foregroundColor: newValue])
        }
    }
}

提示:如果在设置颜色后更改占位符文本-颜色将重置。

Xcode 9.2 Swift 4

extension UITextField{
    @IBInspectable var placeHolderColor: UIColor? {
        get {
            return self.placeHolderColor
        }
        set {
            self.attributedPlaceholder = NSAttributedString(string:self.placeholder != nil ? self.placeholder! : "", attributes:[NSAttributedStringKey.foregroundColor: newValue!])
        }
    }
}