UILabel by WordWrapping 行为不端

Question

这是我的 UILabel 代码...

    var maximumLabelSize: CGSize = (chosenSpecies.identifyingCharacteristics![index] as NSString).sizeWithAttributes([NSFontAttributeName: UIFont.systemFontOfSize(16)])
    var identifyingCharacteristicsInformation = UILabel(frame: (CGRectMake(leftMargin, spacingValue, maximumLabelSize.width, maximumLabelSize.height))) 
    identifyingCharacteristicsInformation.font = UIFont(name: "HelveticaNeue-Light", size: informationTextSize)
    identifyingCharacteristicsInformation.textAlignment = NSTextAlignment.Left
    identifyingCharacteristicsInformation.text = chosenSpecies.identifyingCharacteristics![index]
    identifyingCharacteristicsInformation.text = identifyingCharacteristicsInformation.text!.capitalizedString
    identifyingCharacteristicsInformation.textColor=UIColor(red:0.0, green:0.0, blue:0.0, alpha:1)
    identifyingCharacteristicsInformation.numberOfLines = 0
    identifyingCharacteristicsInformation.lineBreakMode = NSLineBreakMode.ByWordWrapping
    identifyingCharacteristicsInformation.preferredMaxLayoutWidth = pictureContainer.frame.width                  
    ScrollView.addSubview(identifyingCharacteristicsInformation)
    spacingValue += identifyingCharacteristicsInformation.frame.height
    scrollView.contentSize.height += identifyingCharacteristicsInformation.frame.height

这就是发生的事情。这些“特征”中的每一个都是使用上面的代码在 for 循环中打印的。正如您所看到的，那些在屏幕上长时间运行的特征。

http://imgur.com/hbinE5n

我一直在网上搜索为什么这可能会发生几个小时并且一直没有结果。有没有人知道为什么会发生这种情况？我在使用自动换行时遇到了困难，因为我的理解并不完整。只需实现这两行代码，我就可以将它应用到代码中的其他地方。

label.numberOfLines = 0
label.lineBreakMode = NSLineBreakMode.ByWordWrapping

这是我对 Eric Qian 建议的尝试。我目前正在申请它。

var maxSize: CGSize = CGSize(width: 320, height: 100)
var maximumLabelSize: CGRect = (chosenSpecies.identifyingCharacteristics![index] as NSString).boundingRectWithSize(maxSize, options: NSStringDrawingOptions.UsesLineFragmentOrigin, attributes: [NSFontAttributeName: UIFont.systemFontOfSize(16)], context: nil)

Answer 1

检查标签的宽度。我相信它超出了屏幕范围。你需要使用

CGSize maxSize = CGSizeMake(320.0, 1000.0);
CGSize maximumLabelSize = [string boundingRectWithSize:maxSize
                     options:NSStringDrawingUsesLineFragmentOrigin
                  attributes:@{NSFontAttributeName: UIFont.systemFontOfSize(16)} 
                     context:nil];

而不是sizeWithAttributes 以获得正确的字符串大小。由于sizeWithAttributes 将整个字符串呈现在一行中。