使用Swift更改占位符文本颜色

我有一个实现深蓝色的设计UITextField，因为默认情况下，占位符文本为深灰色，所以我几乎无法分辨出占位符文本的含义。

我已经用谷歌搜索了这个问题，但是在使用Swift语言而不是Obj-c时我还没有提出解决方案。

有没有一种方法可以在UITextField使用Swift 的情况下更改占位符文本的颜色？

您可以使用属性字符串设置占位符文本。通过：传递所需的颜色attributes：

var myTextField = UITextField(frame: CGRect(x: 0, y: 0, width: 200, height: 30))
myTextField.backgroundColor = .blue
myTextField.attributedPlaceholder = NSAttributedString(string: "placeholder text",
                             attributes: [NSForegroundColorAttributeName: UIColor.yellow])

对于Swift 3+，请使用以下命令：

myTextField.attributedPlaceholder = NSAttributedString(string: "placeholder text",
                             attributes: [NSAttributedStringKey.foregroundColor: UIColor.white])

对于Swift 4.2，请使用以下命令：

myTextField.attributedPlaceholder = NSAttributedString(string: "placeholder text",
                             attributes: [NSAttributedString.Key.foregroundColor: UIColor.white])

您可以使用Interface Builder快速完成此操作，而无需添加任何代码。

选择，UITextField然后打开右侧的身份检查器：

单击加号按钮并添加新的运行时属性：

placeholderLabel.textColor（快速4）

_placeholderLabel.textColor（Swift 3或以下）

使用颜色作为类型，然后选择颜色。

而已。

在再次运行应用程序之前，您不会看到结果。

UITextField像这样创建扩展：

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!])
        }
    }
}

并在您的情节提要或.xib中。你会看见

在Swift 3.0中，使用

let color = UIColor.lightText
textField.attributedPlaceholder = NSAttributedString(string: textField.placeholder, attributes: [NSForegroundColorAttributeName : color])

在Siwft 5.0中+使用

let color = UIColor.lightText
let placeholder = textField.placeholder ?? "" //There should be a placeholder set in storyboard or elsewhere string or pass empty
textField.attributedPlaceholder = NSAttributedString(string: placeholder, attributes: [NSAttributedString.Key.foregroundColor : color])

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")

让我知道您是否有任何问题。

要为UITextField您的应用中的所有内容一次设置占位符颜色，您可以执行以下操作：

UILabel.appearanceWhenContainedInInstancesOfClasses([UITextField.self]).textColor = UIColor.redColor()

这将为TextField整个应用程序中的所有占位符设置所需的颜色。但仅自iOS 9起可用。

swift的iOS 9之前没有出现方法whenWhen，但是您可以使用Swift中此处提供的解决方案之一

就我而言，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（color：UIColor.white）

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!])
        }
    }
}

斯威夫特4：

txtControl.attributedPlaceholder = NSAttributedString(string: "Placeholder String...",attributes: [NSAttributedStringKey.foregroundColor: UIColor.gray])

目标-C：

UIColor *color = [UIColor grayColor];
txtControl.attributedPlaceholder = [[NSAttributedString alloc] initWithString:@"Placeholder String..." attributes:@{NSForegroundColorAttributeName: color}];

这是我对Swift 4的快速实现：

extension UITextField {
    func placeholderColor(_ color: UIColor){
        var placeholderText = ""
        if self.placeholder != nil{
            placeholderText = self.placeholder!
        }
        self.attributedPlaceholder = NSAttributedString(string: placeholderText, attributes: [NSAttributedStringKey.foregroundColor : color])
    }
}

用途像：

streetTextField?.placeholderColor(AppColor.blueColor)

希望对别人有帮助！

Swift 3（可能是2），您可以在UITextField子类中的占位符上覆盖didSet，以对其应用属性，方法是：

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
    }
}

对于斯威夫特

创建UITextField扩展

extension UITextField{

    func setPlaceHolderColor(){
        self.attributedPlaceholder = NSAttributedString(string: self.placeholder!, attributes: [NSForegroundColorAttributeName : UIColor.white])
    }
}

如果是从情节提要中设置的。

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!])
        }
    }
}

对于Swift 3和3.1，这可以很好地工作：

passField.attributedPlaceholder = NSAttributedString(string: "password", attributes: [NSForegroundColorAttributeName: UIColor.white])

对于Swift 4.0，X-code 9.1版本或iOS 11，您可以使用以下语法来设置不同的占位符颜色

textField.attributedPlaceholder = NSAttributedString(string: "Placeholder Text", attributes: [NSAttributedStringKey.foregroundColor : UIColor.white])

我很惊讶地看到这里有多少糟糕的解决方案。

这是一个始终有效的版本。

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，则颜色将重置。

只需将以下代码写入Appdelegate的didFinishLaunchingWithOptions方法即可，如果您想更改以Swift 4.2编写的整个应用程序，请使用此代码

UILabel.appearance(whenContainedInInstancesOf: [UITextField.self]).textColor = UIColor.white

Crubio的Swift 4答案更新

选择UITextField并在右侧打开身份检查器：

单击加号按钮，然后添加一个新的运行时属性：placeholderLabel.textColor（而不是_placeholderLabel.textColor）

使用颜色作为类型，然后选择颜色。

如果您运行项目，则将看到更改。

对于Swift 4.2及更高版本，您可以按以下步骤操作：

textField.attributedPlaceholder = NSAttributedString(string: "Placeholder Text", attributes: [NSAttributedString.Key.foregroundColor: UIColor.white])

就我而言，我已经完成以下工作：

extension UITextField {
    @IBInspectable var placeHolderColor: UIColor? {
        get {
            if let color = self.attributedPlaceholder?.attribute(.foregroundColor, at: 0, effectiveRange: nil) as? UIColor {
                return color
            }
            return nil
        }
        set (setOptionalColor) {
            if let setColor = setOptionalColor {
                let string = self.placeholder ?? ""
                self.attributedPlaceholder = NSAttributedString(string: string , attributes:[NSAttributedString.Key.foregroundColor: setColor])
            }
        }
    }
}

我在这里编写UITextField的所有UIDesignable。借助此代码，您可以从情节提要中的UI文件检查器直接访问它

@IBDesignable
class CustomTextField: UITextField {

@IBInspectable var leftImage: UIImage? {
    didSet {
        updateView()
    }
}

@IBInspectable var leftPadding: CGFloat = 0 {
    didSet {
        updateView()
    }
}

@IBInspectable var rightImage: UIImage? {
    didSet {
        updateView()
    }
}

@IBInspectable var rightPadding: CGFloat = 0 {
    didSet {
        updateView()
    }
}

private var _isRightViewVisible: Bool = true
var isRightViewVisible: Bool {
    get {
        return _isRightViewVisible
    }
    set {
        _isRightViewVisible = newValue
        updateView()
    }
}

func updateView() {
    setLeftImage()
    setRightImage()

    // Placeholder text color
    attributedPlaceholder = NSAttributedString(string: placeholder != nil ?  placeholder! : "", attributes:[NSAttributedString.Key.foregroundColor: tintColor])
}

func setLeftImage() {
    leftViewMode = UITextField.ViewMode.always
    var view: UIView

    if let image = leftImage {
        let imageView = UIImageView(frame: CGRect(x: leftPadding, y: 0, width: 20, height: 20))
        imageView.image = image
        // Note: In order for your image to use the tint color, you have to select the image in the Assets.xcassets and change the "Render As" property to "Template Image".
        imageView.tintColor = tintColor

        var width = imageView.frame.width + leftPadding

        if borderStyle == UITextField.BorderStyle.none || borderStyle == UITextField.BorderStyle.line {
            width += 5
        }

        view = UIView(frame: CGRect(x: 0, y: 0, width: width, height: 20))
        view.addSubview(imageView)
    } else {
        view = UIView(frame: CGRect(x: 0, y: 0, width: leftPadding, height: 20))
    }

    leftView = view
}

func setRightImage() {
    rightViewMode = UITextField.ViewMode.always

    var view: UIView

    if let image = rightImage, isRightViewVisible {
        let imageView = UIImageView(frame: CGRect(x: 0, y: 0, width: 20, height: 20))
        imageView.image = image
        // Note: In order for your image to use the tint color, you have to select the image in the Assets.xcassets and change the "Render As" property to "Template Image".
        imageView.tintColor = tintColor

        var width = imageView.frame.width + rightPadding

        if borderStyle == UITextField.BorderStyle.none || borderStyle == UITextField.BorderStyle.line {
            width += 5
        }

        view = UIView(frame: CGRect(x: 0, y: 0, width: width, height: 20))
        view.addSubview(imageView)

    } else {
        view = UIView(frame: CGRect(x: 0, y: 0, width: rightPadding, height: 20))
    }

    rightView = view
}


@IBInspectable public var borderColor: UIColor = UIColor.clear {
    didSet {
        layer.borderColor = borderColor.cgColor
    }
}

@IBInspectable public var borderWidth: CGFloat = 0 {
    didSet {
        layer.borderWidth = borderWidth
    }
}

@IBInspectable public var cornerRadius: CGFloat = 0 {
    didSet {
        layer.cornerRadius = cornerRadius
    }
}
@IBInspectable public var bottomBorder: CGFloat = 0 {
    didSet {
       borderStyle = .none
        layer.backgroundColor = UIColor.white.cgColor

        layer.masksToBounds = false
     //   layer.shadowColor = UIColor.gray.cgColor
        layer.shadowOffset = CGSize(width: 0.0, height: 1.0)
        layer.shadowOpacity = 1.0
        layer.shadowRadius = 0.0
    }
}
@IBInspectable public var bottomBorderColor : UIColor = UIColor.clear {
    didSet {

        layer.shadowColor = bottomBorderColor.cgColor
        layer.shadowOffset = CGSize(width: 0.0, height: 1.0)
        layer.shadowOpacity = 1.0
        layer.shadowRadius = 0.0
    }
}
/// Sets the placeholder color
@IBInspectable var placeHolderColor: UIColor? {
    get {
        return self.placeHolderColor
    }
    set {
        self.attributedPlaceholder = NSAttributedString(string:self.placeholder != nil ? self.placeholder! : "", attributes:[NSAttributedString.Key.foregroundColor: newValue!])
    }
}

}

对于斯威夫特

func setPlaceholderColor(textField: UITextField, placeholderText: String) {
    textField.attributedPlaceholder = NSAttributedString(string: placeholderText, attributes: [NSForegroundColorAttributeName: UIColor.pelorBlack])
}

您可以使用它；

self.setPlaceholderColor(textField: self.emailTextField, placeholderText: "E-Mail/Username")

它更多地是关于个性化textField的，但是无论如何，我将共享从另一页获得的代码并使它更好一点：

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]
    )
  }
}

您可以像这样使用它：

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

知道您已UITextField连接到ViewController。

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

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}];

对于Swift：

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

用于更改占位符文本颜色的目标C代码。

首先导入这个objc / runtime类-

#import <objc/runtime.h>

然后替换您的文本字段名称-

Ivar ivar =  class_getInstanceVariable([UITextField class], "_placeholderLabel");
UILabel *placeholderLabel = object_getIvar(YourTxtField, ivar);
placeholderLabel.textColor = [UIColor whiteColor];

适用于iOS13

+(void)ChangeplaceholderColor :(UITextField *)TxtFld andColor:(UIColor*)color { 
    NSMutableAttributedString *placeholderAttributedString = [[NSMutableAttributedString alloc] initWithAttributedString:TxtFld.attributedPlaceholder];
       [placeholderAttributedString addAttribute:NSForegroundColorAttributeName value:color range:NSMakeRange(0, [placeholderAttributedString length])];
       TxtFld.attributedPlaceholder = placeholderAttributedString;

}

在Swift中像这样使用

 let placeHolderText = textField.placeholder ?? ""
 let str = NSAttributedString(string:placeHolderText!, attributes: [NSAttributedString.Key.foregroundColor :UIColor.lightGray])
 textField.attributedPlaceholder = str

在目标C中

NSString *placeHolder = [textField.placeholder length]>0 ? textField.placeholder: @"";
NSAttributedString *str = [[NSAttributedString alloc] initWithString:placeHolder attributes:@{ NSForegroundColorAttributeName : [UIColor lightGrayColor] }];
textField.attributedPlaceholder = str;

    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!])
                }
            } 
}

使用它来添加属性占位符：

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)

对于Swift 4

txtField1.attributedPlaceholder = NSAttributedString(string: "-", attributes: [NSAttributedStringKey.foregroundColor: UIColor.white])

yourTextfield.attributedPlaceholder = NSAttributedString(string: "your placeholder text",attributes: [NSForegroundColorAttributeName: UIColor.white])