iOS Swift: How to count the width of the UILabel. And how to size UICollectionViewCell dynamically with label.

UICollectionView.swift

func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
    let text = collections[indexPath.row].name
    let width = UILabel.textWidth(font: titleFont, text: text)
    return CGSize(width: width + left + right, height: height)
}

UILabel.swift

extension UILabel {
    func textWidth() -> CGFloat {
        return UILabel.textWidth(label: self)
    }
    
    class func textWidth(label: UILabel) -> CGFloat {
        return textWidth(label: label, text: label.text!)
    }
    
    class func textWidth(label: UILabel, text: String) -> CGFloat {
        return textWidth(font: label.font, text: text)
    }
    
    class func textWidth(font: UIFont, text: String) -> CGFloat {
        let myText = text as NSString
        
        let rect = CGSize(width: CGFloat.greatestFiniteMagnitude, height: CGFloat.greatestFiniteMagnitude)
        let labelSize = myText.boundingRect(with: rect, options: .usesLineFragmentOrigin, attributes: [NSFontAttributeName: font], context: nil)
        return ceil(labelSize.width)
    }
}