How to set color of templated image in NSTextAttachment

Question

How can I set the color of a templated image that is an attachment on an attributed string?

Background:

I\'ve got a UILabel and I\'m setting its attributedTe

Answer 1

I use this NSMutableAttributedString extension for Swift.

extension NSMutableAttributedString {
    func addImageAttachment(image: UIImage, font: UIFont, textColor: UIColor, size: CGSize? = nil) {
        let textAttributes: [NSAttributedString.Key: Any] = [
            .strokeColor: textColor,
            .foregroundColor: textColor,
            .font: font
        ]

        self.append(
            NSAttributedString.init(
                //U+200C (zero-width non-joiner) is a non-printing character. It will not paste unnecessary space.
                string: "\u{200c}",
                attributes: textAttributes
            )
        )

        let attachment = NSTextAttachment()
        attachment.image = image.withRenderingMode(.alwaysTemplate)
        //Uncomment to set size of image. 
        //P.S. font.capHeight sets height of image equal to font size.
        //let imageSize = size ?? CGSize.init(width: font.capHeight, height: font.capHeight)
        //attachment.bounds = CGRect(
        //    x: 0,
        //    y: 0,
        //    width: imageSize.width,
        //    height: imageSize.height
        //)
        let attachmentString = NSMutableAttributedString(attachment: attachment)
        attachmentString.addAttributes(
            textAttributes,
            range: NSMakeRange(
                0,
                attachmentString.length
            )
        )
        self.append(attachmentString)
    }
}

This is how to use it.

let attributedString = NSMutableAttributedString()
if let image = UIImage.init(named: "image") {
    attributedString.addImageAttachment(image: image, font: .systemFont(ofSize: 14), textColor: .red)
}

You can also change addImageAttachment's parameter image: UIImage to image: UIImage? and check the nullability in extension.