Make half of the TextView's text color Different than other 50% of the text SWIFT

Question

I've got a large text in my UITextView and I want to make the 50% of the text's color red and the other 50% green . I've added NSMutableAttributedString in the TextView but it works's for the full range of the text . How to divide the textView's text into two sections and color them into red and green ?

let strNumber: NSString = self.text as NSString // TextView Text
        let range = (strNumber).range(of: strNumber as String)
        let attribute = NSMutableAttributedString.init(string: strNumber as String)
        attribute.addAttributes([NSAttributedString.Key.font : UIFont.systemFont(ofSize: 14) , NSAttributedString.Key.foregroundColor : UIColor.red], range: range)
        self.attributedText = attribute

Answer 1

It seems you have an extension to UITextView. The following extension function will make the existing attributed text of a text view be half red and half green. All other existing attributes, if any, will remain.

extension UITextView {
    func makeHalfRedGreen() {
        if let text = self.text {
            let half = text.count / 2
            let halfIndex = text.index(text.startIndex, offsetBy: half)
            let firstRange = NSRange(..<halfIndex, in: text)
            let secondRange = NSRange(halfIndex..., in: text)
            let attrTxt = NSMutableAttributedString(attributedString: attributedText)
            attrTxt.addAttribute(.foregroundColor, value: UIColor.red, range: firstRange)
            attrTxt.addAttribute(.foregroundColor, value: UIColor.green, range: secondRange)
            attributedText = attrTxt
        }
    }
}