对于目标C:

UIColor *color = [UIColor colorWithRed:0.44 green:0.44 blue:0.44 alpha:1.0];
 emailTextField.attributedPlaceholder = [[NSAttributedString alloc] initWithString:@"Friend's Email" attributes:@{NSForegroundColorAttributeName: color}];

迅速:

emailTextField.attributedPlaceholder = NSAttributedString(string: "Friend's Email",
                             attributes: [NSAttributedString.Key.foregroundColor: UIColor.white])

对于目标C:

UIColor *color = [UIColor colorWithRed:0.44 green:0.44 blue:0.44 alpha:1.0];
 emailTextField.attributedPlaceholder = [[NSAttributedString alloc] initWithString:@"Friend's Email" attributes:@{NSForegroundColorAttributeName: color}];

迅速:

emailTextField.attributedPlaceholder = NSAttributedString(string: "Friend's Email",
                             attributes: [NSAttributedString.Key.foregroundColor: UIColor.white])

这段代码在Swift3中工作:

yourTextFieldName .setValue(UIColor.init(colorLiteralRed: 80/255, green: 80/255, blue: 80/255, alpha: 1.0), forKeyPath: "_placeholderLabel.textColor")

如果你有任何问题，请告诉我。

它更多的是个性化你的textField，但无论如何，我将分享这段代码从另一个页面，使它更好一点:

import UIKit
extension UITextField {
func setBottomLine(borderColor: UIColor, fontColor: UIColor, placeHolderColor:UIColor, placeHolder: String) {
    self.borderStyle = UITextBorderStyle.none
    self.backgroundColor = UIColor.clear
    let borderLine = UIView()
    let height = 1.0
    borderLine.frame = CGRect(x: 0, y: Double(self.frame.height) - height, width: Double(self.frame.width), height: height)
    self.textColor = fontColor
    borderLine.backgroundColor = borderColor
    self.addSubview(borderLine)
    self.attributedPlaceholder = NSAttributedString(
        string: placeHolder,
        attributes: [NSAttributedStringKey.foregroundColor: placeHolderColor]
    )
  }
}

你可以这样使用它:

self.textField.setBottomLine(borderColor: lineColor, fontColor: fontColor, placeHolderColor: placeHolderColor, placeHolder: placeHolder)

知道你有一个UITextField连接到一个ViewController。

来源:http://codepany.com/blog/swift-3-custom-uitextfield-with-single-line-input/

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

您可以使用Interface Builder快速完成此任务，而无需添加一行代码。

选择UITextField并打开右边的标识检查器:

点击加号按钮，添加一个新的运行时属性:

placeholderLabel。textColor (Swift 4)

_placeholderLabel。textColor (Swift 3或更少)

使用颜色作为类型并选择颜色。

就是这样。

你不会看到结果，直到你再次运行你的应用程序。