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。
我发现公认的答案适用于固定的宽度,但不适用于固定的高度。对于固定的高度,它只会增加宽度以适应一行中的所有内容,除非文本中有换行符。
width函数多次调用height函数,但这是一个快速计算,在UITable的行中使用该函数时,我没有注意到性能问题。
extension String {
public func height(withConstrainedWidth width: CGFloat, font: UIFont) -> CGFloat {
let constraintRect = CGSize(width: width, height: .greatestFiniteMagnitude)
let boundingBox = self.boundingRect(with: constraintRect, options: .usesLineFragmentOrigin, attributes: [.font : font], context: nil)
return ceil(boundingBox.height)
}
public func width(withConstrainedHeight height: CGFloat, font: UIFont, minimumTextWrapWidth:CGFloat) -> CGFloat {
var textWidth:CGFloat = minimumTextWrapWidth
let incrementWidth:CGFloat = minimumTextWrapWidth * 0.1
var textHeight:CGFloat = self.height(withConstrainedWidth: textWidth, font: font)
//Increase width by 10% of minimumTextWrapWidth until minimum width found that makes the text fit within the specified height
while textHeight > height {
textWidth += incrementWidth
textHeight = self.height(withConstrainedWidth: textWidth, font: font)
}
return ceil(textWidth)
}
}
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
我发现公认的答案适用于固定的宽度,但不适用于固定的高度。对于固定的高度,它只会增加宽度以适应一行中的所有内容,除非文本中有换行符。
width函数多次调用height函数,但这是一个快速计算,在UITable的行中使用该函数时,我没有注意到性能问题。
extension String {
public func height(withConstrainedWidth width: CGFloat, font: UIFont) -> CGFloat {
let constraintRect = CGSize(width: width, height: .greatestFiniteMagnitude)
let boundingBox = self.boundingRect(with: constraintRect, options: .usesLineFragmentOrigin, attributes: [.font : font], context: nil)
return ceil(boundingBox.height)
}
public func width(withConstrainedHeight height: CGFloat, font: UIFont, minimumTextWrapWidth:CGFloat) -> CGFloat {
var textWidth:CGFloat = minimumTextWrapWidth
let incrementWidth:CGFloat = minimumTextWrapWidth * 0.1
var textHeight:CGFloat = self.height(withConstrainedWidth: textWidth, font: font)
//Increase width by 10% of minimumTextWrapWidth until minimum width found that makes the text fit within the specified height
while textHeight > height {
textWidth += incrementWidth
textHeight = self.height(withConstrainedWidth: textWidth, font: font)
}
return ceil(textWidth)
}
}
extension String {
func height(withConstrainedWidth width: CGFloat, font: UIFont) -> CGFloat {
let constraintRect = CGSize(width: width, height: .greatestFiniteMagnitude)
let boundingBox = self.boundingRect(with: constraintRect, options: .usesLineFragmentOrigin, attributes: [NSFontAttributeName: font], context: nil)
return ceil(boundingBox.height)
}
func width(withConstraintedHeight height: CGFloat, font: UIFont) -> CGFloat {
let constraintRect = CGSize(width: .greatestFiniteMagnitude, height: height)
let boundingBox = self.boundingRect(with: constraintRect, options: .usesLineFragmentOrigin, attributes: [NSFontAttributeName: font], context: nil)
return ceil(boundingBox.width)
}
}