How do I make an attributed string using Swift?

Question

I am trying to make a simple Coffee Calculator. I need to display the amount of coffee in grams. The \"g\" symbol for grams needs to be attached to my UILabel that I am usin

Answer 1

Swift 4.2

extension UILabel {

    func boldSubstring(_ substr: String) {
        guard substr.isEmpty == false,
            let text = attributedText,
            let range = text.string.range(of: substr, options: .caseInsensitive) else {
                return
        }
        let attr = NSMutableAttributedString(attributedString: text)
        let start = text.string.distance(from: text.string.startIndex, to: range.lowerBound)
        let length = text.string.distance(from: range.lowerBound, to: range.upperBound)
        attr.addAttributes([NSAttributedStringKey.font: UIFont.boldSystemFont(ofSize: self.font.pointSize)],
                           range: NSMakeRange(start, length))
        attributedText = attr
    }
}