【发布时间】:2014-11-22 10:31:23
【问题描述】:
我的设计实现了深蓝色 UITextField,因为占位符文本默认为深灰色,我几乎看不出占位符文本的含义。
当然,我已经在谷歌上搜索过这个问题,但在使用 Swift 语言而不是 Obj-c 时我还没有想出解决方案。
有没有办法使用 Swift 更改 UITextField 中的占位符文本颜色?
【问题讨论】:
我的设计实现了深蓝色 UITextField,因为占位符文本默认为深灰色,我几乎看不出占位符文本的含义。
当然,我已经在谷歌上搜索过这个问题,但在使用 Swift 语言而不是 Obj-c 时我还没有想出解决方案。
有没有办法使用 Swift 更改 UITextField 中的占位符文本颜色?
【问题讨论】:
您可以使用attributed string 设置占位符文本。只需将您想要的颜色传递给attributes 参数即可。
斯威夫特 5:
let myTextField = UITextField(frame: CGRect(x: 0, y: 0, width: 200, height: 30))
myTextField.backgroundColor = .blue
myTextField.attributedPlaceholder = NSAttributedString(
string: "Placeholder Text",
attributes: [NSAttributedString.Key.foregroundColor: UIColor.white]
)
斯威夫特 3:
myTextField.attributedPlaceholder = NSAttributedString(
string: "Placeholder Text",
attributes: [NSAttributedStringKey.foregroundColor: UIColor.white]
)
老斯威夫特:
myTextField.attributedPlaceholder = NSAttributedString(
string: "Placeholder Text",
attributes: [NSForegroundColorAttributeName: UIColor.white]
)
【讨论】:
myTextField.attributedPlaceholder = NSAttributedString(string: "placeholder text", attributes: [NSForegroundColorAttributeName: UIColor.white])
myTextField.attributedPlaceholder = NSAttributedString(string: myTextField.attributedPlaceholder?.string ?? "", attributes: [NSAttributedString.Key.foregroundColor: UIColor.red])
就我而言,我必须将占位符设置为黑色。我的UITextField 的名字是passwordText。下面的代码在 Swift 5 中进行了测试,对我来说运行良好。我也有相应占位符的现有文本。
let placeholderColor = UIColor.black
passwordText.attributedPlaceholder = NSAttributedString(string: passwordText.placeholder!, attributes: [NSAttributedString.Key.foregroundColor : placeholderColor])
【讨论】:
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!])
}
}
}
【讨论】:
在 Swift 中这样使用,
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;
【讨论】:
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])
【讨论】:
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}];
【讨论】:
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;
}
【讨论】:
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];
【讨论】:
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}];
对于斯威夫特:
emailTextField.attributedPlaceholder = NSAttributedString(string: "Friend's Email",
attributes: [NSAttributedString.Key.foregroundColor: UIColor.white])
【讨论】:
【讨论】:
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(颜色: UIColor.white)
【讨论】:
只需将以下代码写入 Appdelegate 的 didFinishLaunchingWithOptions 方法中如果您想在整个应用中进行更改,请使用此代码,用 Swift 4.2
编写
UILabel.appearance(whenContainedInInstancesOf: [UITextField.self]).textColor = UIColor.white
【讨论】:
我在这里编写 UITextField 的所有 UIDesignable。借助此代码,您可以直接从 Storyboard 中的 UI 文件 Inspector 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!])
}
}
}
【讨论】:
就我而言,我做了以下事情:
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])
}
}
}
}
【讨论】:
我很惊讶这里有多少糟糕的解决方案。
这是一个永远有效的版本。
Swift 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:如果您在设置颜色后更改占位符文本 - 颜色将重置。
【讨论】:
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])
}
}
如果你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!])
}
}
}
【讨论】:
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!])
}
}
}
在您的故事板或 .xib 中。你会看到
【讨论】:
placeHolderColor,此扩展将崩溃您的程序!如果从属性的 getter 返回计算属性本身的值,则将在 getter 内再次调用 getter,从而导致无限递归。 (见:stackoverflow.com/a/42334711/2062785)
attributedString 的第一个字母(如果不为空)并返回其文本颜色,否则返回nil。跨度>
对于 swift 4.2 及更高版本,您可以按以下方式进行操作:
textField.attributedPlaceholder = NSAttributedString(string: "Placeholder Text", attributes: [NSAttributedString.Key.foregroundColor: UIColor.white])
【讨论】:
要为应用中的所有UITextField 设置一次占位符颜色,您可以执行以下操作:
UILabel.appearanceWhenContainedInInstancesOfClasses([UITextField.self]).textColor = UIColor.redColor()
这将为整个应用程序中的所有TextField 占位符设置所需的颜色。但它仅从 iOS 9 开始可用。
在 iOS 9 之前没有出现 swift 中出现的 AppearenceWhenContainedIn....() 方法,但您可以使用此处提供的解决方案之一appearanceWhenContainedIn in Swift
【讨论】:
Swift 3(可能是 2),你可以覆盖 UITextField 子类中占位符上的 didSet 以对其应用属性,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
}
}
【讨论】:
更多的是关于个性化您的文本字段,但无论如何我会分享从另一个页面获取的这段代码并让它变得更好:
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)
知道您有一个UITextField 连接到一个ViewController。
来源:http://codepany.com/blog/swift-3-custom-uitextfield-with-single-line-input/
【讨论】:
对于 Swift 4
txtField1.attributedPlaceholder = NSAttributedString(string: "-", attributes: [NSAttributedStringKey.foregroundColor: UIColor.white])
【讨论】:
crubio 对 Swift 4 的回答更新
Select the UITextField and open the identity inspector on the right:
点击加号按钮并添加一个新的运行时属性:placeholderLabel.textColor(而不是_placeholderLabel.textColor)
使用颜色作为类型并选择颜色。
如果您运行项目,您将看到更改。
【讨论】:
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!])
}
}
}
【讨论】:
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])
}
}
像这样使用:
streetTextField?.placeholderColor(AppColor.blueColor)
希望它对某人有所帮助!
【讨论】:
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])
【讨论】:
对于 Swift 3 和 3.1,这非常有效:
passField.attributedPlaceholder = NSAttributedString(string: "password", attributes: [NSForegroundColorAttributeName: UIColor.white])
【讨论】:
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)
【讨论】:
对于斯威夫特
func setPlaceholderColor(textField: UITextField, placeholderText: String) {
textField.attributedPlaceholder = NSAttributedString(string: placeholderText, attributes: [NSForegroundColorAttributeName: UIColor.pelorBlack])
}
你可以用这个;
self.setPlaceholderColor(textField: self.emailTextField, placeholderText: "E-Mail/Username")
【讨论】:
yourTextfield.attributedPlaceholder = NSAttributedString(string: "your placeholder text",attributes: [NSForegroundColorAttributeName: UIColor.white])
【讨论】: