在NSString或nsmutablestring中不可能有多种颜色。我听说过一点NSAttributedString,它是在iPad SDK 3.2(或大约3.2)中引入的,并且在iPhone SDK 4.0 beta版中可用。

我想要一根有三种颜色的绳子。

我不使用3个独立的NSString的原因,是因为三个NSAttributedString子字符串的长度经常改变,所以我宁愿,不使用任何计算重新定位3个独立的NSString对象。

如果使用NSAttributedString是可能的,我怎么做以下-(如果不可能使用NSAttributedString,你会怎么做):

编辑: 记住,@"first", @"second"和@"third"随时会被其他字符串替换。所以使用硬编码的NSRange值是行不通的。


当前回答

这个方法非常简单。

let text = "This is a colorful attributed string"
let attributedText = 
NSMutableAttributedString.getAttributedString(fromString: text)
attributedText.apply(color: .red, subString: "This")
//Apply yellow color on range
attributedText.apply(color: .yellow, onRange: NSMakeRange(5, 4))

更多详情请点击这里; https://github.com/iOSTechHub/AttributedString

其他回答

我写了helper来方便地添加属性:

- (void)addColor:(UIColor *)color substring:(NSString *)substring;
- (void)addBackgroundColor:(UIColor *)color substring:(NSString *)substring;
- (void)addUnderlineForSubstring:(NSString *)substring;
- (void)addStrikeThrough:(int)thickness substring:(NSString *)substring;
- (void)addShadowColor:(UIColor *)color width:(int)width height:(int)height radius:(int)radius substring:(NSString *)substring;
- (void)addFontWithName:(NSString *)fontName size:(int)fontSize substring:(NSString *)substring;
- (void)addAlignment:(NSTextAlignment)alignment substring:(NSString *)substring;
- (void)addColorToRussianText:(UIColor *)color;
- (void)addStrokeColor:(UIColor *)color thickness:(int)thickness substring:(NSString *)substring;
- (void)addVerticalGlyph:(BOOL)glyph substring:(NSString *)substring;

https://github.com/shmidt/MASAttributes

你也可以通过CocoaPods安装:pod 'MASAttributes', '~> 1.0.0'

我认为,使用正则表达式来查找应用属性的范围是一种非常方便的方法。我是这样做的:

NSMutableAttributedString *goodText = [[NSMutableAttributedString alloc] initWithString:articleText];

NSRange range = [articleText rangeOfString:@"\\[.+?\\]" options:NSRegularExpressionSearch|NSCaseInsensitiveSearch];
if (range.location != NSNotFound) {
    [goodText addAttribute:NSFontAttributeName value:[UIFont fontWithName:@"Georgia" size:16] range:range];
    [goodText addAttribute:NSForegroundColorAttributeName value:[UIColor brownColor] range:range];
}

NSString *regEx = [NSString stringWithFormat:@"%@.+?\\s", [self.article.titleText substringToIndex:0]];
range = [articleText rangeOfString:regEx options:NSRegularExpressionSearch|NSCaseInsensitiveSearch];
if (range.location != NSNotFound) {
    [goodText addAttribute:NSFontAttributeName value:[UIFont fontWithName:@"Georgia-Bold" size:20] range:range];
    [goodText addAttribute:NSForegroundColorAttributeName value:[UIColor blueColor] range:range];
}

[self.textView setAttributedText:goodText];

我正在搜索可用属性的列表,但在这里和类引用的第一页中都没有找到它们。所以我决定在这里发布相关信息。

标准属性

带属性字符串支持以下文本的标准属性。如果键不在字典中,则使用下面描述的默认值。

NSString *NSFontAttributeName;
NSString *NSParagraphStyleAttributeName;
NSString *NSForegroundColorAttributeName;
NSString *NSUnderlineStyleAttributeName;
NSString *NSSuperscriptAttributeName;
NSString *NSBackgroundColorAttributeName;
NSString *NSAttachmentAttributeName;
NSString *NSLigatureAttributeName;
NSString *NSBaselineOffsetAttributeName;
NSString *NSKernAttributeName;
NSString *NSLinkAttributeName;
NSString *NSStrokeWidthAttributeName;
NSString *NSStrokeColorAttributeName;
NSString *NSUnderlineColorAttributeName;
NSString *NSStrikethroughStyleAttributeName;
NSString *NSStrikethroughColorAttributeName;
NSString *NSShadowAttributeName;
NSString *NSObliquenessAttributeName;
NSString *NSExpansionAttributeName;
NSString *NSCursorAttributeName;
NSString *NSToolTipAttributeName;
NSString *NSMarkedClauseSegmentAttributeName;
NSString *NSWritingDirectionAttributeName;
NSString *NSVerticalGlyphFormAttributeName;
NSString *NSTextAlternativesAttributeName;

NSAttributedString编程指南

完整的类参考在这里。

自iOS 7以来,你可以使用NSAttributedString与HTML语法:

NSURL *htmlString = [[NSBundle mainBundle]  URLForResource: @"string"     withExtension:@"html"];
NSAttributedString *stringWithHTMLAttributes = [[NSAttributedString alloc] initWithFileURL:htmlString
                                                                                       options:@{NSDocumentTypeDocumentAttribute:NSHTMLTextDocumentType}
                                                                            documentAttributes:nil
                                                                                         error:nil];
textView.attributedText = stringWithHTMLAttributes;// you can use a label also

你必须添加文件"string.html"到你的项目中,html的内容可以是这样的:

<html>
  <head>
    <style type="text/css">
      body {
        font-size: 15px;
        font-family: Avenir, Arial, sans-serif;
      }
      .red {
        color: red;
      }
      .green {
        color: green;
      }
      .blue {
        color: blue;
      }
    </style>
  </head>
  <body>
    <span class="red">first</span><span class="green">second</span><span class="blue">third</span>
  </body>
</html>  

现在,你可以使用NSAttributedString作为你想要的,即使没有HTML文件,例如:

//At the top of your .m file
#define RED_OCCURENCE -red_occurence-
#define GREEN_OCCURENCE -green_occurence-
#define BLUE_OCCURENCE -blue_occurence-
#define HTML_TEMPLATE @"<span style=\"color:red\">-red_occurence-</span><span style=\"color:green\">-green_occurence-</span><span style=\"color:blue\">-blue_occurence-</span></body></html>"

//Where you need to use your attributed string
NSString *string = [HTML_TEMPLATE stringByReplacingOccurrencesOfString:RED_OCCURENCE withString:@"first"] ;
string = [string stringByReplacingOccurrencesOfString:GREEN_OCCURENCE   withString:@"second"];
string = [string stringByReplacingOccurrencesOfString:BLUE_OCCURENCE    withString:@"third"];

NSData* cData = [string dataUsingEncoding:NSUTF8StringEncoding];

NSAttributedString *stringWithHTMLAttributes = [[NSAttributedString alloc] initWithData:cData
                                                                                options:@{NSDocumentTypeDocumentAttribute:NSHTMLTextDocumentType}
                                                                        documentAttributes:nil
                                                                                     error:nil];
textView.attributedText = stringWithHTMLAttributes;

这个解对任何长度都适用

NSString *strFirst = @"Anylengthtext";
NSString *strSecond = @"Anylengthtext";
NSString *strThird = @"Anylengthtext";

NSString *strComplete = [NSString stringWithFormat:@"%@ %@ %@",strFirst,strSecond,strThird];

NSMutableAttributedString *attributedString =[[NSMutableAttributedString alloc] initWithString:strComplete];

[attributedString addAttribute:NSForegroundColorAttributeName
              value:[UIColor redColor]
              range:[strComplete rangeOfString:strFirst]];

[attributedString addAttribute:NSForegroundColorAttributeName
              value:[UIColor yellowColor]
              range:[strComplete rangeOfString:strSecond]];

[attributedString addAttribute:NSForegroundColorAttributeName
              value:[UIColor blueColor]
              range:[strComplete rangeOfString:strThird]];


self.lblName.attributedText = attributedString;

我做了一个库,使这更容易。看看ZenCopy吧。

您可以创建Style对象,和/或将它们设置为稍后引用的键。是这样的:

ZenCopy.manager.config.setStyles {
    return [
        "token": Style(
            color: .blueColor(), // optional
            // fontName: "Helvetica", // optional
            fontSize: 14 // optional
        )
    ]
}

然后,你可以很容易地构造字符串和样式,并有参数:)

label.attributedText = attributedString(
                                ["$0 ".style("token") "is dancing with ", "$1".style("token")], 
                          args: ["JP", "Brock"]
)

你也可以很容易地用正则表达式搜索样式!

let atUserRegex = "(@[A-Za-z0-9_]*)"
mutableAttributedString.regexFind(atUserRegex, addStyle: "token")

这将使用'token'样式对前面带有'@'的所有单词进行样式化。(例如@jpmcglone)

我需要仍然得到它工作w/一切NSAttributedString所提供的,但我认为fontName, fontSize和颜色涵盖了它的大部分。期待很快会有很多更新:)

如果你需要,我可以帮你开始。同时也在寻求反馈,所以如果它能让你的生活更轻松,我就说任务完成了。