我想改变我在UITextField控件中设置的占位符文本的颜色,使其为黑色。

我更喜欢这样做,而不使用普通文本作为占位符,并且不得不重写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

那么我就能做这个了。但是我不确定如何从这个方法中访问实际的占位符对象。


当前回答

我能做的最好的iOS7和更少的是:

- (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];
  }
}

其他回答

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
    }
}

iOS 6及后续版本在UITextField上提供attributedPlaceholder。 iOS 3.2及更高版本提供了setAttributes:range: on 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;

我能做的最好的iOS7和更少的是:

- (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];
  }
}

对于设置属性文本字段占位符与多种颜色,

只要指定文本,

  //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:

对于那些使用Monotouch (Xamarin.iOS)的人,这里是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);
    }
}