在Swift中根据字符串计算UILabel的大小

我试图计算基于不同字符串长度的UILabel的高度。

func calculateContentHeight() -> CGFloat{
    var maxLabelSize: CGSize = CGSizeMake(frame.size.width - 48, CGFloat(9999))
    var contentNSString = contentText as NSString
    var expectedLabelSize = contentNSString.boundingRectWithSize(maxLabelSize, options: NSStringDrawingOptions.UsesLineFragmentOrigin, attributes: [NSFontAttributeName: UIFont.systemFontOfSize(16.0)], context: nil)
    print("\(expectedLabelSize)")
    return expectedLabelSize.size.height

}

上面是我用来确定高度的当前函数，但它不起作用。如果能得到任何帮助，我将不胜感激。我更喜欢Swift的答案，而不是Objective C。

当前回答

extension String{

    func widthWithConstrainedHeight(_ height: CGFloat, font: UIFont) -> CGFloat {
        let constraintRect = CGSize(width: CGFloat.greatestFiniteMagnitude, height: height)

        let boundingBox = self.boundingRect(with: constraintRect, options: NSStringDrawingOptions.usesLineFragmentOrigin, attributes: [NSFontAttributeName: font], context: nil)

        return ceil(boundingBox.width)
    }

    func heightWithConstrainedWidth(_ width: CGFloat, font: UIFont) -> CGFloat? {
        let constraintRect = CGSize(width: width, height: CGFloat.greatestFiniteMagnitude)
        let boundingBox = self.boundingRect(with: constraintRect, options: NSStringDrawingOptions.usesLineFragmentOrigin, attributes: [NSFontAttributeName: font], context: nil)

        return ceil(boundingBox.height)
    }

}

2018-05-14 12:21:45

其他回答

检查标签文本的高度和它正在工作

let labelTextSize = ((labelDescription.text)! as NSString).boundingRect(
                with: CGSize(width: labelDescription.frame.width, height: .greatestFiniteMagnitude),
                options: .usesLineFragmentOrigin,
                attributes: [.font: labelDescription.font],
                context: nil).size
            if labelTextSize.height > labelDescription.bounds.height {
                viewMoreOrLess.hide(byHeight: false)
                viewLess.hide(byHeight: false)
            }
            else {
                viewMoreOrLess.hide(byHeight: true)
                viewLess.hide(byHeight: true)

            }

2019-03-20 05:11:15

这个解决方案将有助于在运行时计算高度和宽度。

    let messageText = "Your Text String"
    let size = CGSize.init(width: 250, height: 1000)
    let options = NSStringDrawingOptions.usesFontLeading.union(.usesLineFragmentOrigin)
    let estimateFrame = NSString(string: messageText).boundingRect(with:  size, options: options, attributes: [NSAttributedString.Key.font: UIFont(name: "HelveticaNeue", size: 17)!], context: nil)

在这里，你可以计算你的字符串的估计高度，并将其传递给UILabel框架。

estimateFrame.Width
estimateFrame.Height

2019-11-11 05:32:18

这里有一个简单的解决方案，对我来说很有用。类似于其他发布的一些，但它不需要sizeToFit

注意这是用Swift 5写的

let lbl = UILabel()
lbl.numberOfLines = 0
lbl.font = UIFont.systemFont(ofSize: 12) // make sure you set this correctly 
lbl.text = "My text that may or may not wrap lines..."

let width = 100.0 // the width of the view you are constraint to, keep in mind any applied margins here
 
let height = lbl.systemLayoutSizeFitting(CGSize(width: width, height: UIView.layoutFittingCompressedSize.height), withHorizontalFittingPriority: .required, verticalFittingPriority: .fittingSizeLevel).height

它处理行换行等。不是最优雅的代码，但它完成了工作。

2019-07-01 19:51:03

我创建了以下扩展来根据宽度计算字符串的高度。

   extension String {
    func heightWithConstrainedWidth(width: CGFloat, font: UIFont) -> CGFloat {
        let textView = UITextView()
        textView.text = self
        textView.font = font
        var newFrame = textView.frame
        newFrame.size = CGSize(width: width, height: .greatestFiniteMagnitude)
        textView.frame = newFrame
        return textView.contentSize.height
    }

2022-07-11 16:55:25

斯威夫特5:

如果你有UILabel和某种方式boundingRect不为你工作(我面临这个问题。它总是返回1行高)有一个扩展，可以轻松计算标签大小。

extension UILabel {
    func getSize(constrainedWidth: CGFloat) -> CGSize {
        return systemLayoutSizeFitting(CGSize(width: constrainedWidth, height: UIView.layoutFittingCompressedSize.height), withHorizontalFittingPriority: .required, verticalFittingPriority: .fittingSizeLevel)
    }
}

你可以这样使用它:

let label = UILabel()
label.text = "My text\nIs\nAwesome"
let labelSize = label.getSize(constrainedWidth:200.0)

对我有用

2020-05-21 11:27:52

在Swift中根据字符串计算UILabel的大小

推荐文章

最新文章

标签