ios - 如何根据字体大小和文本计算标签的大小？

Question

我在我的应用程序的 View 上添加了一个标签。我给它指定了一些大小字体大小为 16.0。当标签中的文本很小时，它工作正常。但是当文本是更多标签我希望标签自动增加它的高度并更新约束。所以我不想要任何与约束相关的警告。最好的方法是什么？编辑

    cell.label_like_count.lineBreakMode = NSLineBreakByWordWrapping;
    cell.label_like_count.numberOfLines = 0;
    [cell.label_like_count sizeToFit];
    NSString *first_like_user=@"Some Name";
    int count=[first_like_user length];
    NSString *like_count=@"12";
    like_count=[like_count stringByAppendingString:@" others like your post"];
    first_like_user=[first_like_user stringByAppendingString:@" and "];
    first_like_user=[first_like_user stringByAppendingString:like_count];
    NSMutableAttributedString *mutableAttributeStr = [[NSMutableAttributedString alloc]initWithString:first_like_user];

    NSAttributedString *attributeStr = [[NSAttributedString alloc]initWithString:@"\n" attributes:@{NSFontAttributeName : [UIFont fontWithName:@"HelveticaNeue-Bold" size:8]}];

    [mutableAttributeStr addAttribute:NSFontAttributeName value: [UIFont fontWithName:@"Helvetica-Bold" size:14.0] range:NSMakeRange(0, count)];

    [mutableAttributeStr appendAttributedString:attributeStr];

我试过下面的代码

  CGSize maximumLabelSize = CGSizeMake(296,9999);

    CGSize expectedLabelSize = [first_like_user sizeWithFont:cell.label_like_count.font
                                      constrainedToSize:maximumLabelSize
                                          lineBreakMode:cell.label_like_count.lineBreakMode];

    //adjust the label the the new height.
    CGRect newFrame = cell.label_like_count.frame;
    newFrame.size.height = expectedLabelSize.height;
    cell.label_like_count.frame = newFrame;

    [cell.label_like_count setAttributedText:mutableAttributeStr];

但这不会增加标签高度&标签不会进入多行？

Answer 1

除非您指定明确的高度限制，否则 UILabel 会通过 intrinsicContentSize 自动计算它们的高度限制。您所要做的就是确定标签的宽度(通过显式宽度约束或通过左/右边缘约束)，它会根据内容调整其高度。