byWordWrappingな文字列に必要な高さを求めてみる

gistfile1.txt

func heightForStringDrawing2(myString: String, myFont: NSFont, myWidth: CGFloat) -> CGFloat {
    let paragraphStyle = NSMutableParagraphStyle()
    paragraphStyle.lineBreakMode = .byWordWrapping
    let attribute: [String : Any] = [
        NSFontAttributeName: myFont,
        NSParagraphStyleAttributeName: paragraphStyle
    ]
    let constraintsSize = CGSize(width: myWidth, height: CGFloat(FLT_MAX))
    let textSize = NSString(string: myString).boundingRect(with: constraintsSize, options: .usesLineFragmentOrigin, attributes: attribute, context: nil)
    return textSize.height
}