Ios 如何知道UILabel中的单词是否被剪切

我尝试开发自动收缩功能。我已将文本属性设置为固定大小

UILabel

。之后，我降低字体大小，检查文本是否适合给定的容器大小

问题是

UILabel

忽略

NSLineBreakByWordWrapping

，如果一个单词长于容器宽度。导致我有剪尾字

代码如下：

- (void) setCardText:(NSString *)txt {
    NSMutableAttributedString *attributedString = [[NSMutableAttributedString alloc] initWithString:txt];
    NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc] init];
    [paragraphStyle setLineBreakMode:NSLineBreakByWordWrapping];
    [paragraphStyle setAlignment:NSTextAlignmentCenter];
    [attributedString addAttribute:NSParagraphStyleAttributeName value:paragraphStyle range:NSMakeRange(0, [txt length])];
    self.cardLabel.attributedText = attributedString;

    for (CGFloat fontSize = 40; fontSize >=5; fontSize--) {
        [self.cardLabel setFont:[UIFont fontWithName:@"GothamPro-Light" size:fontSize]];
        [paragraphStyle setLineSpacing:fontSize*0.3f];
        [attributedString addAttribute:NSParagraphStyleAttributeName value:paragraphStyle range:NSMakeRange(0, [txt length])];
        self.cardLabel.lineBreakMode = NSLineBreakByWordWrapping;
        [self.cardLabel sizeToFit];
        if (self.cardLabel.frame.size.width <= 220) {
            [self.cardLabel setFrame:CGRectMake(40, 40, 220, self.cardLabel.frame.size.height)];
        }
        if (self.cardLabel.frame.size.height <= 210) {
            [self.cardLabel setFrame:CGRectMake(40, 40, self.cardLabel.frame.size.width, 210)];
        }
        if (self.cardLabel.frame.size.width <= 220 && self.cardLabel.frame.size.height <= 210) {
            [self.cardLabel setFrame:CGRectMake(40, 40, 220, 210)];
            break;
        }
    };

-（void）setCardText:（NSString*）txt{
NSMUTABLeAttributeString*AttributeString=[[NSMUTABLeAttributeString alloc]initWithString:txt]；
NSMutableParagraphStyle*paragraphStyle=[[NSMutableParagraphStyle alloc]init]；
[段落样式setLineBreakMode:NSLineBreakByWordWrapping]；
[段落样式setAlignment:NSTextAlignmentCenter]；
[attributedString addAttribute:NSParagraphStyleAttributeName值：段落样式范围：NSMakeRange（0，[txt长度]）；
self.cardLabel.attributedText=attributedString；
对于（CGFloat fontSize=40；fontSize>=5；fontSize--）{
[self.cardLabel setFont:[UIFont fontWithName:@“GothamPro Light”大小：fontSize]；
[段落样式设置行距：fontSize*0.3f]；
[attributedString addAttribute:NSParagraphStyleAttributeName值：段落样式范围：NSMakeRange（0，[txt长度]）；
self.cardLabel.lineBreakMode=NSLineBreakByWordWrapping；
[self.cardlelabel sizeToFit]；
如果（self.cardLabel.frame.size.width您尝试过该属性吗？
sizeToFit方法调用sizeThatFits:它返回“最佳”大小以适应当前的边界，然后调整标签的大小。因此，首先您约束标签，它必须适应给定的宽度。您可以看到-Wrapping的描述出现在单词边界处，除非单词本身不适合一行

出于您的目的，您应该允许标签的宽度比要求的宽度更宽。但这很困难，因为任务是找到最佳字体大小，而我们无法预测宽度。最好的方法是根据文本中最长的单词找到字体大小

因此，算法：

通过空格分隔来检测最长的单词
迭代地减小字体大小，并在单词大于所需宽度时计算最长单词的大小
将计算字体设置为全文，并调用sizeThatFits
请在下面找到示例代码（“Verdana”字体用于测试）

是的，但它在我的情况下不起作用，文字仍然被剪切。我尝试在我的
中对
循环使用
adjustsFontSizeToFit
，对
静音
adjustsFontSizeToFitWidth
是常用的解决方案，但它只对单行标签有效。是的，除了使用
组件部分，我做了相同的逻辑atedByCharactersInSet
，得到了没有附加标点符号的干净单词。但是你的方法更适合我。谢谢！
- (void) setText {
    NSString * text = @"Incidental, indirect, secondary, side rival - Побочный, косвенный, второстепенный, боковой соперник";
    CGFloat maxWidth = 300.;
    [self setText:text toLabel:self.label maxWidth:maxWidth];
}

- (void) setText:(NSString *)text
         toLabel:(UILabel*)label
        maxWidth:(CGFloat)maxWidth
{
    CGFloat fontSize = [self fontSizeOfWord:[self theLongestWord:text]
                            initialFontSize:40.
                         constrainedByWidth:maxWidth];

    NSMutableAttributedString * attributedString = [self attributedStringForText:text];
    [self setupAttributedStirng:attributedString withFontWithSize:fontSize];
    label.attributedText = attributedString;
    CGRect labelFrame = label.frame;
    labelFrame.size = [label sizeThatFits:[attributedString sizeAdaptedForWidth:maxWidth]];
    label.frame = labelFrame;
}

- (NSString*) theLongestWord:(NSString*)text {
    NSArray * words = [text componentsSeparatedByString:@" "];
    NSUInteger longestLength = 0;
    NSUInteger index = NSNotFound;
    for(int i = 0; i < words.count; i++) {
        NSString * word = words[i];
        CGFloat length = word.length;
        if(length > longestLength) {
            longestLength = length;
            index = i;
        }
    }
    return (index != NSNotFound ? words[index] : nil);
}

- (CGFloat)fontSizeOfWord:(NSString *)word
          initialFontSize:(CGFloat)initialFontSize
       constrainedByWidth:(CGFloat)maxWidth
{
    NSMutableAttributedString * wordString = [self attributedStringForText:word];
    CGFloat fontSize = initialFontSize;
    for (; fontSize >= 5.; --fontSize) {
        [self setupAttributedStirng:wordString
                   withFontWithSize:fontSize];
        CGSize wordSize = [wordString sizeAdaptedForWidth:CGFLOAT_MAX];
        if(wordSize.width <= maxWidth){
            break;
        }
    }
    return fontSize;
}

- (NSMutableAttributedString*) attributedStringForText:(NSString*)text {
    return (text&&text.length ? [[NSMutableAttributedString alloc] initWithString:text]:nil);
}

- (void)setupAttributedStirng:(NSMutableAttributedString *)attributedString
             withFontWithSize:(CGFloat)fontSize
{
    NSMutableParagraphStyle *paragraphStyle = [NSMutableParagraphStyle new];
    [paragraphStyle setLineBreakMode:NSLineBreakByWordWrapping];
    [paragraphStyle setAlignment:NSTextAlignmentCenter];
    UIFont * font = [UIFont fontWithName:@"Verdana" size:fontSize];
    [paragraphStyle setLineSpacing:fontSize*0.3f];
    NSDictionary * attributes = @{NSParagraphStyleAttributeName: paragraphStyle,
                                  NSFontAttributeName: font};
    [attributedString addAttributes:attributes
                              range:NSMakeRange(0, [attributedString length])];
}

@implementation NSAttributedString (AdaptedSize)

- (CGSize) sizeAdaptedForWidth:(CGFloat)width
{
    CTFramesetterRef framesetter = CTFramesetterCreateWithAttributedString((__bridge CFAttributedStringRef)self);
    CGSize targetSize = CGSizeMake(width, CGFLOAT_MAX);
    CGSize fitSize = CTFramesetterSuggestFrameSizeWithConstraints(framesetter,
                                                                  CFRangeMake(0, [self length]),
                                                                  NULL, targetSize, NULL);
    CFRelease(framesetter);
    return fitSize;
}

@end