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
为了解决这类问题，我在swift中创建了一个名为Atributika的库。
let str = "<r>first</r><g>second</g><b>third</b>".style(tags:
Style("r").foregroundColor(.red),
Style("g").foregroundColor(.green),
Style("b").foregroundColor(.blue)).attributedString
label.attributedText = str
你可以在这里找到它https://github.com/psharanda/Atributika
其他回答
带属性字符串扩展的更简单的解决方案。
extension NSMutableAttributedString {
// this function attaches color to string
func setColorForText(textToFind: String, withColor color: UIColor) {
let range: NSRange = self.mutableString.range(of: textToFind, options: .caseInsensitive)
self.addAttribute(NSAttributedStringKey.foregroundColor, value: color, range: range)
}
}
试试这个，看看(在Swift 3和4中测试)
let label = UILabel()
label.frame = CGRect(x: 120, y: 100, width: 200, height: 30)
let first = "first"
let second = "second"
let third = "third"
let stringValue = "\(first)\(second)\(third)" // or direct assign single string value like "firstsecondthird"
let attributedString: NSMutableAttributedString = NSMutableAttributedString(string: stringValue)
attributedString.setColorForText(textToFind: first, withColor: UIColor.red) // use variable for string "first"
attributedString.setColorForText(textToFind: "second", withColor: UIColor.green) // or direct string like this "second"
attributedString.setColorForText(textToFind: third, withColor: UIColor.blue)
label.font = UIFont.systemFont(ofSize: 26)
label.attributedText = attributedString
self.view.addSubview(label)
以下是预期结果:
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;
源
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
- (void)changeColorWithString:(UILabel *)uilabel stringToReplace:(NSString *) stringToReplace uiColor:(UIColor *) uiColor{
NSMutableAttributedString *text =
[[NSMutableAttributedString alloc]
initWithAttributedString: uilabel.attributedText];
[text addAttribute: NSForegroundColorAttributeName value:uiColor range:[uilabel.text rangeOfString:stringToReplace]];
[uilabel setAttributedText: text];
}
我总是发现使用带属性的字符串是一个令人难以置信的漫长而乏味的过程。
所以我做了一个Mac应用程序，为你创建所有的代码。
https://itunes.apple.com/us/app/attributed-string-creator/id730928349?mt=12
