Data to attributedString with font attributes Swift

Question

I have an RTF file with which I was able to get contents as Data (i want it to be in Data to use it elsewhere in code). Howeever, I would like to add styling to the attributedString like font before assigning to label. Im struck on how to apply these attributes in below code. Please advice how i can achieve same. Here's my code

let rtfData = getRTFData()
guard let data = rtfData else {
        return
    }
if let attributedString = try? NSAttributedString(data: data, options: [.documentType: NSAttributedString.DocumentType.rtf], documentAttributes: nil) {
        myLabel.attributedText = attributedString
 }

Here i wanted to add attributes to attributedString like let boldAttributes: [NSAttributedString.Key: Any] = [.font: UIFont.boldSystemFont(ofSize: 14)] and apply these attributes to attributedText

Answer 1

If you want to append font attribute to existing attributes this one should work:

if let attributedString = try? NSMutableAttributedString(data: data, options: [.documentType: NSAttributedString.DocumentType.rtf], documentAttributes: nil) {
   var attrs = attributedString.attributes(at: 0, effectiveRange: nil)
   attrs[NSAttributedString.Key.font] = UIFont.boldSystemFont(ofSize: 14)
   attributedString.setAttributes(attrs, range: NSRange(location: 0, length: attributedString.length))
   myLabel.attributedText = attributedString
}