31

所以我有一个NSAttributedString我想在bullet point一段文本的开头插入一个。我怎样才能做到这一点？当我显示文本时，如何创建一个CTPAragraphStyle创建此项目符号点的？

编辑： 应该在iOS上可用

4

6 回答 6

39

这是一种适用于 iOS6 的更现代的方法：

NSMutableAttributedString * string = [[NSMutableAttributedString alloc] initWithString:@"•\texample bullet fill out the text to check what happens on the second line and make sure it is lining up OK"];

NSMutableParagraphStyle *paragraphStyle;
paragraphStyle = [[NSParagraphStyle defaultParagraphStyle] mutableCopy];
[paragraphStyle setTabStops:@[[[NSTextTab alloc] initWithTextAlignment:NSTextAlignmentLeft location:15 options:nil]]];
[paragraphStyle setDefaultTabInterval:15];
[paragraphStyle setFirstLineHeadIndent:0];
[paragraphStyle setHeadIndent:15];

[string addAttributes:@{NSParagraphStyleAttributeName: paragraphStyle} range:NSMakeRange(0,[string length])];
于 2014-09-12T07:52:25.363 回答
36

最简单的一点： [mutableAttributedString insertAttributedString: @"•\t" atIndex:0];

难点。大致如下。（这是从一个更大的项目中提取的，但它可能会给你一个不错的开始。）

NSMutableAttributedString * string = [[NSMutableAttributedString alloc] initWithString:@"•\texample bullet fill out the text to check what happens on the second line and make sure it is lining up OK"];

CTTextAlignment alignment = kCTLeftTextAlignment;
CGFloat paragraphSpacing = 0.0;
CGFloat paragraphSpacingBefore = 0.0;
CGFloat firstLineHeadIndent = 15.0;
CGFloat headIndent = 30.0;

CGFloat firstTabStop = 15.0; // width of your indent
CGFloat lineSpacing = 0.45;

CTTextTabRef tabArray[] = { CTTextTabCreate(0, firstTabStop, NULL) };

CFArrayRef tabStops = CFArrayCreate( kCFAllocatorDefault, (const void**) tabArray, 1, &kCFTypeArrayCallBacks );
CFRelease(tabArray[0]);

CTParagraphStyleSetting altSettings[] = 
{
    { kCTParagraphStyleSpecifierLineSpacing, sizeof(CGFloat), &lineSpacing},
    { kCTParagraphStyleSpecifierAlignment, sizeof(CTTextAlignment), &alignment},
    { kCTParagraphStyleSpecifierFirstLineHeadIndent, sizeof(CGFloat), &firstLineHeadIndent},
    { kCTParagraphStyleSpecifierHeadIndent, sizeof(CGFloat), &headIndent},
    { kCTParagraphStyleSpecifierTabStops, sizeof(CFArrayRef), &tabStops},
    { kCTParagraphStyleSpecifierParagraphSpacing, sizeof(CGFloat), &paragraphSpacing},
    { kCTParagraphStyleSpecifierParagraphSpacingBefore, sizeof(CGFloat), &paragraphSpacingBefore}
}; 

CTParagraphStyleRef style;
style = CTParagraphStyleCreate( altSettings, sizeof(altSettings) / sizeof(CTParagraphStyleSetting) );

if ( style == NULL )
{
    NSLog(@"*** Unable To Create CTParagraphStyle in apply paragraph formatting" );
    return;
}

[string addAttributes:[NSDictionary dictionaryWithObjectsAndKeys:(NSObject*)style,(NSString*) kCTParagraphStyleAttributeName, nil] range:NSMakeRange(0,[string length])];

CFRelease(tabStops);
CFRelease(style);

您需要包含 CoreText 框架，然后导入 CoreText/CoreText.h

于 2011-07-11T00:28:52.713 回答
35

这是 Swift 的一个很好的解决方案

let label = UILabel()
label.frame = CGRect(x: 40, y: 100, width: 280, height: 600)
label.textColor = UIColor.lightGray
label.numberOfLines = 0

let arrayString = [
    "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.",
    "Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.",
    "Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur.",
    "Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum."
]

label.attributedText = add(stringList: arrayString, font: label.font, bullet: "")

self.view.addSubview(label)

添加项目符号属性

斯威夫特 4.2++

func add(stringList: [String],
         font: UIFont,
         bullet: String = "\u{2022}",
         indentation: CGFloat = 20,
         lineSpacing: CGFloat = 2,
         paragraphSpacing: CGFloat = 12,
         textColor: UIColor = .gray,
         bulletColor: UIColor = .green) -> NSAttributedString {

    let textAttributes: [NSAttributedString.Key: Any] = [NSAttributedString.Key.font: font, NSAttributedString.Key.foregroundColor: textColor]
    let bulletAttributes: [NSAttributedString.Key: Any] = [NSAttributedString.Key.font: font, NSAttributedString.Key.foregroundColor: bulletColor]

    let paragraphStyle = NSMutableParagraphStyle()
    let nonOptions = [NSTextTab.OptionKey: Any]()
    paragraphStyle.tabStops = [
        NSTextTab(textAlignment: .left, location: indentation, options: nonOptions)]
    paragraphStyle.defaultTabInterval = indentation
    //paragraphStyle.firstLineHeadIndent = 0
    //paragraphStyle.headIndent = 20
    //paragraphStyle.tailIndent = 1
    paragraphStyle.lineSpacing = lineSpacing
    paragraphStyle.paragraphSpacing = paragraphSpacing
    paragraphStyle.headIndent = indentation

    let bulletList = NSMutableAttributedString()
    for string in stringList {
        let formattedString = "\(bullet)\t\(string)\n"
        let attributedString = NSMutableAttributedString(string: formattedString)

        attributedString.addAttributes(
            [NSAttributedString.Key.paragraphStyle : paragraphStyle],
            range: NSMakeRange(0, attributedString.length))

        attributedString.addAttributes(
            textAttributes,
            range: NSMakeRange(0, attributedString.length))

        let string:NSString = NSString(string: formattedString)
        let rangeForBullet:NSRange = string.range(of: bullet)
        attributedString.addAttributes(bulletAttributes, range: rangeForBullet)
        bulletList.append(attributedString)
    }

    return bulletList
}

斯威夫特 4.0 & 4.1

func add(stringList: [String],
         font: UIFont,
         bullet: String = "\u{2022}",
         indentation: CGFloat = 20,
         lineSpacing: CGFloat = 2,
         paragraphSpacing: CGFloat = 12,
         textColor: UIColor = .gray,
         bulletColor: UIColor = .green) -> NSAttributedString {

    let textAttributes: [NSAttributedStringKey: Any] = [NSAttributedStringKey.font: font, NSAttributedStringKey.foregroundColor: textColor]
    let bulletAttributes: [NSAttributedStringKey: Any] = [NSAttributedStringKey.font: font, NSAttributedStringKey.foregroundColor: bulletColor]

    let paragraphStyle = NSMutableParagraphStyle()
    let nonOptions = [NSTextTab.OptionKey: Any]()
    paragraphStyle.tabStops = [
        NSTextTab(textAlignment: .left, location: indentation, options: nonOptions)]
    paragraphStyle.defaultTabInterval = indentation
    //paragraphStyle.firstLineHeadIndent = 0
    //paragraphStyle.headIndent = 20
    //paragraphStyle.tailIndent = 1
    paragraphStyle.lineSpacing = lineSpacing
    paragraphStyle.paragraphSpacing = paragraphSpacing
    paragraphStyle.headIndent = indentation

    let bulletList = NSMutableAttributedString()
    for string in stringList {
        let formattedString = "\(bullet)\t\(string)\n"
        let attributedString = NSMutableAttributedString(string: formattedString)

        attributedString.addAttributes(
            [NSAttributedStringKey.paragraphStyle : paragraphStyle],
            range: NSMakeRange(0, attributedString.length))

        attributedString.addAttributes(
            textAttributes,
            range: NSMakeRange(0, attributedString.length))

        let string:NSString = NSString(string: formattedString)
        let rangeForBullet:NSRange = string.range(of: bullet)
        attributedString.addAttributes(bulletAttributes, range: rangeForBullet)
        bulletList.append(attributedString)
    }

    return bulletList
}

这是结果：

在此处输入图像描述

于 2017-10-26T10:32:31.230 回答
5

您不会在 iOS 中实现带有段落样式的项目符号列表。根据需要设置制表位，然后在段落开头插入制表符、项目符号、制表符。

CTParagraphStyle非常不灵活，因此您不能只添加您选择的新样式。但是，您可以将您喜欢的任何属性 ( MYBulletStyle) 添加到NSAttributedString. 这对于传递项目符号列表信息非常有用，NSAttributedString然后在您准备好显示项目符号时重建字符串以包含项目符号。但 Core Text 不会自动为您呈现项目符号。

于 2011-07-11T00:05:27.547 回答
4

这是 Krunal 在Objective-C中的出色回答。它还删除了最后一个项目符号上的段落间距，以避免 UILabel 上的额外底部填充。

UILabel *label = [UILabel new];
label.frame = CGRectMake(40, 100, 280, 600);
label.textColor = UIColor.lightGrayColor;
label.numberOfLines = 0;

NSArray *stringArray = @[@"Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.",
                         @"Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.",
                         @"Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur.",
                         @"Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum."
                         ];

label.attributedText = [self attributedStringForBulletTexts:stringArray
                                                   withFont:label.font
                                               bulletString:@""
                                                indentation:20
                                                lineSpacing:2
                                           paragraphSpacing:12
                                                  textColor:UIColor.grayColor
                                                bulletColor:UIColor.greenColor];

这是创建实际属性文本的函数：

- (NSAttributedString *)attributedStringForBulletTexts:(NSArray *)stringList
                                              withFont:(UIFont *)font
                                          bulletString:(NSString *)bullet
                                           indentation:(CGFloat)indentation
                                           lineSpacing:(CGFloat)lineSpacing
                                      paragraphSpacing:(CGFloat)paragraphSpacing
                                             textColor:(UIColor *)textColor
                                           bulletColor:(UIColor *)bulletColor {

    NSDictionary *textAttributes = @{NSFontAttributeName: font,
                                 NSForegroundColorAttributeName: textColor};
    NSDictionary *bulletAttributes = @{NSFontAttributeName: font, NSForegroundColorAttributeName: bulletColor};

    NSMutableParagraphStyle *paragraphStyle = [NSMutableParagraphStyle new];
    paragraphStyle.tabStops = @[[[NSTextTab alloc] initWithTextAlignment: NSTextAlignmentLeft location:indentation options:@{}]];
    paragraphStyle.defaultTabInterval = indentation;
    paragraphStyle.lineSpacing = lineSpacing;
    paragraphStyle.paragraphSpacing = paragraphSpacing;
    paragraphStyle.headIndent = indentation;

    NSMutableAttributedString *bulletList = [NSMutableAttributedString new];

    for (NSString *string in stringList) {
        NSString *formattedString = [NSString stringWithFormat:@"%@\t%@\n", bullet, string];
        NSMutableAttributedString *attributedString = [[NSMutableAttributedString alloc] initWithString:formattedString];
        if ([string isEqualToString: stringList.lastObject]) {
            paragraphStyle = [paragraphStyle mutableCopy];
            paragraphStyle.paragraphSpacing = 0;
        }
        [attributedString addAttributes:@{NSParagraphStyleAttributeName: paragraphStyle} range:NSMakeRange(0, attributedString.length)];
        [attributedString addAttributes:textAttributes range:NSMakeRange(0, attributedString.length)];

        NSRange rangeForBullet = [formattedString rangeOfString:bullet];
        [attributedString addAttributes:bulletAttributes range:rangeForBullet];
        [bulletList appendAttributedString:attributedString];
    }

    return bulletList;
}
于 2018-07-18T16:10:56.800 回答
2

不是这个问题的实际答案，但这可以提供帮助。

只需添加“•”

甚至我也在为我的 textView 寻找类似的东西。我所做的，只需在上面的字符串中附加我的字符​​串并将其传递给我的 textView，标签也可以这样做。我为未来的观众回答了这个问题。

于 2013-07-23T15:21:00.123 回答