iPhone UITextField - 更改占位符文本颜色

Question

我想更改我在UITextField控件中设置的占位符文字的颜色，使其变黑。

我更喜欢这样做而不使用普通文本作为占位符，并且必须覆盖所有方法来模仿占位符的行为。

我相信如果我重写这个方法：

- (void)drawPlaceholderInRect:(CGRect)rect

然后我应该能够做到这一点。但是我不确定如何从这个方法中访问实际的占位符对象。

Answer 1

自iOS 6中的UIViews中引入属性字符串以来，可以为占位符文本指定颜色，如下所示：

if ([textField respondsToSelector:@selector(setAttributedPlaceholder:)]) {
  UIColor *color = [UIColor blackColor];
  textField.attributedPlaceholder = [[NSAttributedString alloc] initWithString:placeholderText attributes:@{NSForegroundColorAttributeName: color}];
} else {
  NSLog(@"Cannot set placeholder text's color, because deployment target is earlier than iOS 6.0");
  // TODO: Add fall-back code to set placeholder color.
}

Answer 2

轻松无痛，对某些人来说可能是一种简单的选择。

_placeholderLabel.textColor

不建议用于制作，Apple可能会拒绝您的提交。

Answer 3

您可以覆盖drawPlaceholderInRect:(CGRect)rect，以手动呈现占位符文字：

- (void) drawPlaceholderInRect:(CGRect)rect {
    [[UIColor blueColor] setFill];
    [[self placeholder] drawInRect:rect withFont:[UIFont systemFontOfSize:16]];
}

Answer 4

您可以使用以下代码将占位符文本颜色更改为您想要的任何颜色。

UIColor *color = [UIColor lightTextColor];
YOURTEXTFIELD.attributedPlaceholder = [[NSAttributedString alloc] initWithString:@"PlaceHolder Text" attributes:@{NSForegroundColorAttributeName: color}];

Answer 5

也许您想尝试这种方式，但Apple可能会警告您访问私人ivar：

[self.myTextField setValue:[UIColor darkGrayColor] 
                forKeyPath:@"_placeholderLabel.textColor"];

注意
根据MartinAlléus的说法，这不再适用于iOS 7。

Answer 6

这适用于Swift＆lt; 3.0：

myTextField.attributedPlaceholder = 
NSAttributedString(string: "placeholder text", attributes: [NSForegroundColorAttributeName : UIColor.redColor()])

在iOS 8.2和iOS 8.3 beta 4中测试。

斯威夫特3：

myTextfield.attributedPlaceholder =
NSAttributedString(string: "placeholder text", attributes: [NSForegroundColorAttributeName : UIColor.red])

斯威夫特4：

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

Swift 4.2：

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

Answer 7

在斯威夫特：

if let placeholder = yourTextField.placeholder {
    yourTextField.attributedPlaceholder = NSAttributedString(string:placeholder, 
        attributes: [NSForegroundColorAttributeName: UIColor.blackColor()])
}

在Swift 4.0中：

if let placeholder = yourTextField.placeholder {
    yourTextField.attributedPlaceholder = NSAttributedString(string:placeholder, 
        attributes: [NSAttributedStringKey.foregroundColor: UIColor.black])
}

Answer 8

以下仅适用于iOS6 +（如Alexander W的评论所示）：

UIColor *color = [UIColor grayColor];
nameText.attributedPlaceholder =
   [[NSAttributedString alloc]
       initWithString:@"Full Name"
       attributes:@{NSForegroundColorAttributeName:color}];

Answer 9

Swift 3.0 +故事板

要在故事板中更改占位符颜色，请使用下一个代码创建扩展名。 （随意更新此代码，如果您认为，它可以更清晰，更安全）。

extension UITextField {
    @IBInspectable var placeholderColor: UIColor {
        get {
            guard let currentAttributedPlaceholderColor = attributedPlaceholder?.attribute(NSForegroundColorAttributeName, at: 0, effectiveRange: nil) as? UIColor else { return UIColor.clear }
            return currentAttributedPlaceholderColor
        }
        set {
            guard let currentAttributedString = attributedPlaceholder else { return }
            let attributes = [NSForegroundColorAttributeName : newValue]

            attributedPlaceholder = NSAttributedString(string: currentAttributedString.string, attributes: attributes)
        }
    }
}

Swift 4版本

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

Swift 5版本

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

Answer 10

有了这个，我们可以改变iOS中文本字段的占位符文本的颜色

[self.userNameTxt setValue:[UIColor colorWithRed:41.0/255.0 green:91.0/255.0 blue:106.0/255.0 alpha:1.0] forKeyPath:@"_placeholderLabel.textColor"];

Answer 11

我已经遇到过这个问题。在我的情况下，代码是正确的。

目标C

[textField setValue:[UIColor whiteColor] forKeyPath:@"_placeholderLabel.textColor"];

适用于Swift 4.X

tf_mobile.setValue(UIColor.white, forKeyPath: "_placeholderLabel.textColor")

希望，这可能会对你有帮助。

Answer 12

为什么不使用UIAppearance方法：

[[UILabel appearanceWhenContainedIn:[UITextField class], nil] setTextColor:[UIColor whateverColorYouNeed]];

Answer 13

同样在你的故事板中，没有单行代码

Answer 14

适用于iOS 6.0 +

[textfield setValue:your_color forKeyPath:@"_placeholderLabel.textColor"];

希望它有所帮助。

注意： 当我们访问私有API时，Apple可能拒绝（0.01％几率）您的应用。我在两年后的所有项目中都使用了这个，但Apple没有要求这样做。

Answer 15

对于Xamarin.iOS开发人员，我从本文档中找到了它 https://developer.xamarin.com/api/type/Foundation.NSAttributedString/

textField.AttributedPlaceholder = new NSAttributedString ("Hello, world",new UIStringAttributes () { ForegroundColor =  UIColor.Red });

Answer 16

Swift版本。可能会对某人有所帮助。

class TextField: UITextField {
   override var placeholder: String? {
        didSet {
            let placeholderString = NSAttributedString(string: placeholder!, attributes: [NSForegroundColorAttributeName: UIColor.whiteColor()])
            self.attributedPlaceholder = placeholderString
        }
    }
}

Answer 17

在iOS7中处理垂直和水平对齐以及占位符的颜色。 drawInRect和drawAtPoint不再使用当前上下文fillColor。

https://developer.apple.com/library/ios/documentation/StringsTextFonts/Conceptual/TextAndWebiPhoneOS/CustomTextProcessing/CustomTextProcessing.html

Obj-C

@interface CustomPlaceHolderTextColorTextField : UITextField

@end


@implementation CustomPlaceHolderTextColorTextField : UITextField


-(void) drawPlaceholderInRect:(CGRect)rect  {
    if (self.placeholder) {
        // color of placeholder text
        UIColor *placeHolderTextColor = [UIColor redColor];

        CGSize drawSize = [self.placeholder sizeWithAttributes:[NSDictionary dictionaryWithObject:self.font forKey:NSFontAttributeName]];
        CGRect drawRect = rect;

        // verticially align text
        drawRect.origin.y = (rect.size.height - drawSize.height) * 0.5;

        // set alignment
        NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc] init];
        paragraphStyle.alignment = self.textAlignment;

        // dictionary of attributes, font, paragraphstyle, and color
        NSDictionary *drawAttributes = @{NSFontAttributeName: self.font,
                                     NSParagraphStyleAttributeName : paragraphStyle,
                                     NSForegroundColorAttributeName : placeHolderTextColor};


        // draw
        [self.placeholder drawInRect:drawRect withAttributes:drawAttributes];
    }
}

@end

Answer 18

分类FTW。可以进行优化以检查有效的颜色变化。

---

#import <UIKit/UIKit.h>

@interface UITextField (OPConvenience)

@property (strong, nonatomic) UIColor* placeholderColor;

@end

#import "UITextField+OPConvenience.h"

@implementation UITextField (OPConvenience)

- (void) setPlaceholderColor: (UIColor*) color {
    if (color) {
        NSMutableAttributedString* attrString = [self.attributedPlaceholder mutableCopy];
        [attrString setAttributes: @{NSForegroundColorAttributeName: color} range: NSMakeRange(0,  attrString.length)];
        self.attributedPlaceholder =  attrString;
    }
}

- (UIColor*) placeholderColor {
    return [self.attributedPlaceholder attribute: NSForegroundColorAttributeName atIndex: 0 effectiveRange: NULL];
}

@end

Answer 19

iOS 6及更高版本在attributedPlaceholder上提供UITextField。 iOS 3.2及更高版本在setAttributes:range:上提供NSMutableAttributedString。

您可以执行以下操作：

NSMutableAttributedString *ms = [[NSMutableAttributedString alloc] initWithString:self.yourInput.placeholder];
UIFont *placeholderFont = self.yourInput.font;
NSRange fullRange = NSMakeRange(0, ms.length);
NSDictionary *newProps = @{NSForegroundColorAttributeName:[UIColor yourColor], NSFontAttributeName:placeholderFont};
[ms setAttributes:newProps range:fullRange];
self.yourInput.attributedPlaceholder = ms;

Answer 20

覆盖drawPlaceholderInRect:将是正确的方法，但由于API（或文档）中的错误，它无法正常工作。

永远不会在UITextField上调用该方法。

另见drawTextInRect on UITextField not called

您可以使用digdog的解决方案。由于我不确定这是否超过了Apples评论，我选择了另一种解决方案：使用我自己的标签覆盖文本字段，模仿占位符行为。

但这有点乱。 代码看起来像这样（注意我在TextField的子类中执行此操作）：

@implementation PlaceholderChangingTextField

- (void) changePlaceholderColor:(UIColor*)color
{    
    // Need to place the overlay placeholder exactly above the original placeholder
    UILabel *overlayPlaceholderLabel = [[[UILabel alloc] initWithFrame:CGRectMake(self.frame.origin.x + 8, self.frame.origin.y + 4, self.frame.size.width - 16, self.frame.size.height - 8)] autorelease];
    overlayPlaceholderLabel.backgroundColor = [UIColor whiteColor];
    overlayPlaceholderLabel.opaque = YES;
    overlayPlaceholderLabel.text = self.placeholder;
    overlayPlaceholderLabel.textColor = color;
    overlayPlaceholderLabel.font = self.font;
    // Need to add it to the superview, as otherwise we cannot overlay the buildin text label.
    [self.superview addSubview:overlayPlaceholderLabel];
    self.placeholder = nil;
}

Answer 21

我是xcode的新手，我找到了解决相同效果的方法。

我用一个uilabel代替了所需格式的占位符并将其隐藏在

中

- (void)textFieldDidBeginEditing:(UITextField *)textField
{
    switch (textField.tag)
    {
        case 0:
            lblUserName.hidden=YES;
            break;

        case 1:
            lblPassword.hidden=YES;
            break;

        default:
            break;
    }
}

我同意它的解决方案而不是真正的解决方案，但效果与此相同link

注意：仍适用于iOS 7：|

Answer 22

此Swift 4.1解决方案

    textName.attributedPlaceholder = NSAttributedString(string: textName.placeholder!, attributes: [NSAttributedStringKey.foregroundColor : UIColor.red])

Answer 23

[txt_field setValue:ColorFromHEX(@"#525252") forKeyPath:@"_placeholderLabel.textColor"];

Answer 24

我能为iOS7及更低版本做的最好的是：

- (CGRect)placeholderRectForBounds:(CGRect)bounds {
  return [self textRectForBounds:bounds];
}

- (CGRect)editingRectForBounds:(CGRect)bounds {
  return [self textRectForBounds:bounds];
}

- (CGRect)textRectForBounds:(CGRect)bounds {
  CGRect rect = CGRectInset(bounds, 0, 6); //TODO: can be improved by comparing font size versus bounds.size.height
  return rect;
}

- (void)drawPlaceholderInRect:(CGRect)rect {
  UIColor *color =RGBColor(65, 65, 65);
  if (SYSTEM_VERSION_GREATER_THAN_OR_EQUAL_TO(@"7.0")) {
    [self.placeholder drawInRect:rect withAttributes:@{NSFontAttributeName:self.font, UITextAttributeTextColor:color}];
  } else {
    [color setFill];
    [self.placeholder drawInRect:rect withFont:self.font];
  }
}

Answer 25

对于那些使用Monotouch（Xamarin.iOS）的人来说，这是Adam的答案，翻译成C＃：

public class MyTextBox : UITextField
{
    public override void DrawPlaceholder(RectangleF rect)
    {
        UIColor.FromWhiteAlpha(0.5f, 1f).SetFill();
        new NSString(this.Placeholder).DrawString(rect, Font);
    }
}

Answer 26

在swift 3.X中

/assets/fonts/glyphicons-halflings-regular.woff

Answer 27

带CAVEAT的Swift 5。

let attributes = [ NSAttributedString.Key.foregroundColor: UIColor.someColor ]
let placeHolderString = NSAttributedString(string: "DON'T_DELETE", attributes: attributes)
txtField.attributedPlaceholder = placeHolderString

告诫您必须输入一个非空的String，其中“ DON'T_DELETE”在哪，即使该字符串是在其他代码中设置的也是如此。可能省去您五分钟的时间。

Answer 28

我需要保持占位符一致，所以亚当的回答对我来说还不够。

为了解决这个问题，我使用了一个小变体，希望对你们有些帮助：

- (void) drawPlaceholderInRect:(CGRect)rect {
    //search field placeholder color
    UIColor* color = [UIColor whiteColor];

    [color setFill];
    [self.placeholder drawInRect:rect withFont:self.font lineBreakMode:UILineBreakModeTailTruncation alignment:self.textAlignment];
}

Answer 29

设置具有多种颜色的属性文本字段占位符

只需指定文字

即可

  //txtServiceText is your Textfield
 _txtServiceText.placeholder=@"Badal/ Shah";
    NSMutableAttributedString *mutable = [[NSMutableAttributedString alloc] initWithString:_txtServiceText.placeholder];
     [mutable addAttribute: NSForegroundColorAttributeName value:[UIColor whiteColor] range:[_txtServiceText.placeholder rangeOfString:@"Badal/"]]; //Replace it with your first color Text
    [mutable addAttribute: NSForegroundColorAttributeName value:[UIColor orangeColor] range:[_txtServiceText.placeholder rangeOfString:@"Shah"]]; // Replace it with your secondcolor string.
    _txtServiceText.attributedPlaceholder=mutable;

输出： -

Answer 30

另一个不需要子类化的选项 - 将占位符留空，并在编辑按钮的顶部放置一个标签。像管理占位符一样管理标签（清除一旦用户输入任何内容......）

Answer 31

在Swift 3中

import UIKit

let TEXTFIELD_BLUE  = UIColor.blue
let TEXTFIELD_GRAY  = UIColor.gray

class DBTextField: UITextField {
    /// Tetxfield Placeholder Color
    @IBInspectable var palceHolderColor: UIColor = TEXTFIELD_GRAY
    func setupTextField () {
        self.attributedPlaceholder = NSAttributedString(string:self.placeholder != nil ? self.placeholder! : "",
                                                            attributes:[NSForegroundColorAttributeName: palceHolderColor])
    }
}

class DBLocalizedTextField : UITextField {
    override func awakeFromNib() {
        super.awakeFromNib()
        self.placeholder = self.placeholder
    }
}

Answer 32

我建议另一个解决方案。由于占位符文本使用文本字段的默认字体设置，因此只需将初始字体颜色设置为所需的占位符字体颜色即可。然后设置UITextField的委托并实现以下方法：

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
    //set color for text input
    textField.textColor = [UIColor blackColor];
    return YES;
}

- (BOOL)textFieldShouldClear:(UITextField *)textField
{
    //set color for placeholder text
    textField.textColor = [UIColor redColor];
    return YES;
}

因此，如果用户开始在文本字段中键入内容，则文本颜色会变为黑色，并且在文本字段再次清除后，占位符文本将再次显示为红色。

干杯， ANKA