How to set font size on NSAttributedString

Question

Edit - This has been marked as duplicate, but as I state below, I am looking for a Swift solution. Everything I've found is written in Objective C.

I am trying to convert HTML into an NSAttributedString, but can't figure how to set the font style and size. All of the examples are in Objective C which I'm not skilled in. How can I set the font style/size to System 15 (as an example)

private func stringFromHtml(string: String) -> NSAttributedString? {
        do {
            let data = string.data(using: String.Encoding.utf8, allowLossyConversion: true)
            if let d = data {
                let str = try NSAttributedString(data: d,
                                                 options: [NSDocumentTypeDocumentAttribute: NSHTMLTextDocumentType],                                                  documentAttributes: nil)
                return str
            }
        } catch {
        }
        return nil
    }

EDIT...... I've tried several ways. I can't get it to work. I'm now getting an error message: Type of expression is ambiguous without more context. It's pointing to the NSAttributedString I've tried the following:

let myAttribute = [ NSForegroundColorAttributeName: UIColor.blue ]
let data = string.data(using: String.Encoding.utf8, allowLossyConversion: true)
  if let d = data {
     let str = try NSAttributedString(data: d,
                       attributes: myAttribute,
                       options: [NSDocumentTypeDocumentAttribute: NSHTMLTextDocumentType], documentAttributes: nil)

Answer 1

let myString = "Swift Attributed String"
let myAttribute = [ NSForegroundColorAttributeName: UIColor.blue ]
let myAttrString = NSAttributedString(string: myString, attributes: myAttribute) 

// set attributed text on a UILabel
myLabel.attributedText = myAttrString

Font

let myAttribute = [ NSFontAttributeName: UIFont(name: "Chalkduster", size: 18.0)! ]

Shadow

let myShadow = NSShadow()
myShadow.shadowBlurRadius = 3
myShadow.shadowOffset = CGSize(width: 3, height: 3)
myShadow.shadowColor = UIColor.gray
let myAttribute = [ NSShadowAttributeName: myShadow ]

Underline

let myAttribute = [ NSUnderlineStyleAttributeName: NSUnderlineStyle.StyleSingle.rawValue ]

Textcolor

let myAttribute = [ NSForegroundColorAttributeName: UIColor.blue ]

Background Color

let myAttribute = [ NSBackgroundColorAttributeName: UIColor.yellow ]

Answer 2

In Swift you can use:

let stringWithAttribute = NSAttributedString(string: selectedFilter ?? "",
                                             attributes: [NSAttributedStringKey.font: UIFont.systemFont(ofSize: 14.0)])

Answer 3

The only thing that worked for me is to wrap the HTML in a <span> and apply the style there:

let modifiedFontString = "<span style=\"font-family: Lato-Regular; font-size: 14; color: rgb(60, 60, 60)\">" + originalHTMLString + "</span>"

Try this extension:

extension String {

    var htmlToAttributedString: NSAttributedString? {
        guard let data = data(using: .utf8) else { return NSAttributedString() }
        do {
            return try NSAttributedString(data: data, options: [.documentType: NSAttributedString.DocumentType.html, .characterEncoding:String.Encoding.utf8.rawValue], documentAttributes: nil)
        } catch {
            return NSAttributedString()
        }
    }

    var htmlToString: String {
        return htmlToAttributedString?.string ?? ""
    }

    func convertToAttributedString() -> NSAttributedString? {
        let modifiedFontString = "<span style=\"font-family: Lato-Regular; font-size: 14; color: rgb(60, 60, 60)\">" + self + "</span>"
        return modifiedFontString.htmlToAttributedString
    }
}

And you use it like this:

someLabel.attributedString = someHTMLString.convertToAttributedString()

Hope it helps!

Answer 4

Please Check this one

var attrString = NSAttributedString(string: "labelText", attributes: [NSForegroundColorAttributeName: UIColor.red, NSFontAttributeName: UIFont(name: "system", size: 12)])
label.attributedText = attrString

Answer 5

Check this for swift 5:

extension String {
    func getAttributedString<T>(_ key: NSAttributedString.Key, value: T) -> NSAttributedString {
       let applyAttribute = [ key: T.self ]
       let attrString = NSAttributedString(string: self, attributes: applyAttribute)
       return attrString
    }
}

You can check more attributes styles here: https://developer.apple.com/documentation/foundation/nsattributedstring/key

USE

// Background Color
let attributedString = "YOUR_STRING".getAttributedString(.backgroundColor, value: UIColor.blue)

// Forground Color
let attributedString = "YOUR_STRING".getAttributedString(.foregroundColor, value: UIColor.red)

// Font
let attributedString = "YOUR_STRING".getAttributedString(.font, value: UIFont.boldSystemFont(ofSize: 15))

// Underline
let attributedString = "YOUR_STRING".getAttributedString(.underlineStyle, value: NSUnderlineStyle.single)

// Underline Color
let attributedString = "YOUR_STRING".getAttributedString(.underlineColor, value: UIColor.black)

    
// set attributed text on a UILabel
yourLabel.attributedText = attributedString

Answer 6

First you need to convert data to string then use this peice of code

let  attributes = [
   NSForegroundColorAttributeName: UIColor.black,
            ]
try NSAttributedString(string: "", attributes: attributes)

Answer 7

you can set this way

let attribute: [String : Any] = [NSFontAttributeName: UIFont.systemFont(ofSize: UIFont.systemFontSize, weight: UIFontWeightThin),
    NSForegroundColorAttributeName: UIColor.red]

let attributedText = NSAttributedString(string: "Your String", attributes: attribute)