How to select a text in a textView having a NSRange in Swift?

Question

I have a UITextView where I would like to select a part of the text. I'm trying to use selectedTextRange, unfortunately I get this error:

Cannot convert value of type 'NSRange' (aka '_NSRange') to expected argument type 'UITextRange'

This is the code I'm trying to use:

mainTextField.becomeFirstResponder()
mainTextField.selectedTextRange = mainTextField.textInRange(matchRange) // matchRange is a NSRange

The range I'm using is coming from a Regex which I adapted from this tutorial 1:

EDIT: added the first line

if let regex =  NSRegularExpression(options: searchOptions){ // refers to an installed extension convenience init
let range = NSMakeRange(0, (mainTextField.text.characters.count))
let matches = regex.matchesInString(mainTextField.text, options: [], range: range)
[...]

Please share the declaration of your `regex` variable too – Victor Sigler Jun 20 '16 at 20:30 — Victor Sigler, Jun 20 '16 at 20:30
Thank you Victor Sigler, I added it. – Cue Jun 20 '16 at 21:58 — Cue, Jun 20 '16 at 21:58

beyowulf · Accepted Answer · 2016-06-20T22:10:18.993

You can add an extension on UITextView that will do the conversion.

    extension UITextView
    {
        func textRangeFromNSRange(range:NSRange) -> UITextRange?
        {
            let beginning = self.beginningOfDocument
            guard let start = self.positionFromPosition(beginning, offset: range.location), end = self.positionFromPosition(start, offset: range.length) else { return nil}

            return self.textRangeFromPosition(start, toPosition: end)
        }
    }

Use

    if let range = mainTextView.textRangeFromNSRange(range: matchRange){
        mainTextField.selectedTextRange = range
    }

Where matchRange is an NSRange and range is a UITextRange

score 1 · Answer 2 · answered Jan 22 '19 at 14:33

Swift 4 updated version of @beyowulf's answer:

extension UITextView {

    func textRangeFromNSRange(range:NSRange) -> UITextRange? {
        let beginning = beginningOfDocument
        guard let start = position(from: beginning, offset: range.location), let end = position(from: start, offset: range.length) else { return nil }

        return textRange(from: start, to: end)
    }
}

Cue · Answer 3 · 2016-06-20T23:41:39.450

Just to add a little more information, I found also an alternative way: instead of using selectedTextRange and doing the conversion, you can use selectedRange.

Note: matchRange is a NSRange

// this don't work because selectedTextRange requires an UITextRange
textField.selectedTextRange = textField.textInRange(matchRange) // don't work

// this works because selectedRange requires a NSRange
textField.selectedRange = matchRange // works

How to select a text in a textView having a NSRange in Swift?

3 Answers3