如何制作具有多种颜色的单个 UILabel答案

【问题标题】：How to make a single UILabel with multiple colors如何制作具有多种颜色的单个 UILabel
【发布时间】：2014-07-11 08:26:15
【问题描述】：

我想创建一个具有 2 种颜色的 uilabel。第一种颜色是黑色，另一种是蓝色。

我可以在其中使用多个 uilabel，但我只想有一个 uilabel。有什么办法可以实现吗？

这应该是输出。

这是我的代码：

UILabel * lblPostContent = [[UILabel alloc] initWithFrame:CGRectMake((ICON_PADDING*1.5), 42, container.frame.size.width-30, 34)];
lblPostContent.numberOfLines =0;
[lblPostContent setFont:[UIFont systemFontOfSize:11]];
[lblPostContent setText:[NSString stringWithFormat:@"I just scored %d points at %@ using the iBowl app", score, LuckyStrikes]];
[container addSubview:lblPostContent];

【问题讨论】：

查看NSMutableAttributedString 的文档

标签： ios uilabel nsattributedstring uicolor textcolor

【解决方案1】：

你应该使用属性......像这样

NSMutableAttributedString *text = [[NSMutableAttributedString alloc] initWithString:yourString];
[text addAttribute: NSForegroundColorAttributeName value: [UIColor blackColor] range: NSMakeRange(0, TXTTOBEBLACKLENGTH)];
[text addAttribute: NSForegroundColorAttributeName value: [UIColor blueColor] range: NSMakeRange(TXTTOBEBLACKLENGTH, TXTTOBEBLBLUELENGTH)];
[lblPostContent setAttributedText: text];

【讨论】：

【解决方案2】：

为避免计算部分文本的长度并生成NSRanges，您可以使用appendAttributedString: 从组件NSAttributedString 对象组成最终的NSMutableAttributedString，如下所示：

UIColor *normalColor = [UIColor blackColor];
UIColor *highlightColor = [UIColor blueColor];
UIFont *font = [UIFont systemFontOfSize:12.0];        
NSDictionary *normalAttributes = @{NSFontAttributeName:font, NSForegroundColorAttributeName:normalColor};
NSDictionary *highlightAttributes = @{NSFontAttributeName:font, NSForegroundColorAttributeName:highlightColor};

NSAttributedString *normalText = [[NSAttributedString alloc] initWithString:@"Normal " attributes:normalAttributes];
NSAttributedString *highlightedText = [[NSAttributedString alloc] initWithString:@"Highlighted" attributes:highlightAttributes];

NSMutableAttributedString *finalAttributedString = [[NSMutableAttributedString alloc] initWithAttributedString:normalText];
[finalAttributedString appendAttributedString:highlightedText];

self.label.attributedText = finalAttributedString;

【讨论】：

【解决方案3】：

这里是 AttributedString 的扩展函数：

extension NSMutableAttributedString {

    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)
    }

}

使用标签试试：

let label = UILabel()
label.frame = CGRect(x: 40, y: 100, width: 280, height: 200)
let first = "89"
let second = "Lucky Strikes"
let third = "iBowl app"
let stringValue = "I just scored \(first) points at \(second) using the \(third)"  // or direct assign single string value like "firstsecondthird"
label.textColor = UIColor.lightGray
label.numberOfLines = 0
let attributedString: NSMutableAttributedString = NSMutableAttributedString(string: stringValue)
attributedString.setColorForText(textToFind: first, withColor: UIColor.blue)   // use variable for string "89"
attributedString.setColorForText(textToFind: second, withColor: UIColor.blue) // or direct string like this "Lucky Strikes"
attributedString.setColorForText(textToFind: third, withColor: UIColor.blue)
label.font = UIFont.systemFont(ofSize: 26)
label.attributedText = attributedString
self.view.addSubview(label)

结果如下：

【讨论】：