Changing specific text's color using NSMutableAttributedString in Swift

Question

The issue I am having is that I want to be able to change the textColor of certain text in a TextView. I am using a concatenated string, and just want the strings I am appending into the TextView's text. It appears that what I want to use is NSMutableAttributedString, but I am not finding any resources of how to use this in Swift. What I have so far is something like this:

let string = "A \(stringOne) with \(stringTwo)"
var attributedString = NSMutableAttributedString(string: string)
textView.attributedText = attributedString

From here I know I need to find the range of words that need to have their textColor changed and then add them to the attributed string. What I need to know is how to find the correct strings from the attributedString, and then change their textColor.

Since I have too low of a rating I can't answer my own question, but here is the answer I found

I found my own answer by translating from translating some code from

Change attributes of substrings in a NSAttributedString

Here is the example of implementation in Swift:

let string = "A \(stringOne) and \(stringTwo)"
var attributedString = NSMutableAttributedString(string:string)

let stringOneRegex = NSRegularExpression(pattern: nameString, options: nil, error: nil)
let stringOneMatches = stringOneRegex.matchesInString(longString, options: nil, range: NSMakeRange(0, attributedString.length))
for stringOneMatch in stringOneMatches {
    let wordRange = stringOneMatch.rangeAtIndex(0)
    attributedString.addAttribute(NSForegroundColorAttributeName, value: UIColor.nameColor(), range: wordRange)
}

textView.attributedText = attributedString

Since I am wanting to change the textColor of multiple Strings I will make a helper function to handle this, but this works for changing the textColor.

Do you know how to do it in Objective-C? Have you attempted rewriting that same code in Swift? — Aaron Brager, Aug 08 '14 at 16:01
Here is a really good answer: https://stackoverflow.com/a/37992022/426571 — el_quick, Apr 29 '20 at 01:30

score 151 · Answer 1 · edited Sep 04 '20 at 14:41

let mainString = "Hello World"
let stringToColor = "World"

SWIFT 5

let range = (mainString as NSString).range(of: stringToColor)

let mutableAttributedString = NSMutableAttributedString.init(string: mainString)
mutableAttributedString.addAttribute(NSAttributedString.Key.foregroundColor, value: UIColor.red, range: range)

textField = UITextField.init(frame: CGRect(x:10, y:20, width:100, height: 100))
textField.attributedText = mutableAttributedString

SWIFT 4.2

let range = (mainString as NSString).range(of: stringToColor)
    

let mutableAttributedString = NSMutableAttributedString.init(string: mainString)
mutableAttributedString.addAttribute(NSAttributedStringKey.foregroundColor, value: UIColor.red, range: range)     
    
textField = UITextField.init(frame: CGRect(x:10, y:20, width:100, height: 100))
textField.attributedText = mutableAttributedString

what if the string is big, and has many duplicated (similar) words. will range(of: ... ) works? — Hatim, Feb 11 '20 at 15:03

score 113 · Answer 2 · edited Apr 10 '18 at 15:41

113

I see you have answered the question somewhat, but to provide a slightly more concise way without using regex to answer to the title question:

To change the colour of a length of text you need to know the start and end index of the coloured-to-be characters in the string e.g.

var main_string = "Hello World"
var string_to_color = "World"

var range = (main_string as NSString).rangeOfString(string_to_color)

Then you convert to attributed string and use 'add attribute' with NSForegroundColorAttributeName:

var attributedString = NSMutableAttributedString(string:main_string)
attributedString.addAttribute(NSForegroundColorAttributeName, value: UIColor.redColor() , range: range)

A list of further standard attributes you can set can be found in Apple's documentation

edited Apr 10 '18 at 15:41

brimstone

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answered Aug 11 '14 at 16:52

James Alvarez

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NSColor is OSX only - use UIColor for IOS – Stephen O'Connor Dec 20 '14 at 13:07
3

What if i have var main_string = "Hello World Hello World Hello World" and i need to apply color on "World" in whole string? – msmq Jun 14 '16 at 10:42
`main_string`, `string_to_color` and `range` were never mutated. Consider changing them to `let` constant? – Cesare May 07 '17 at 20:46

score 48 · Answer 3 · answered Jan 03 '16 at 12:45

48

Swift 2.1 Update:

 let text = "We tried to make this app as most intuitive as possible for you. If you have any questions don't hesitate to ask us. For a detailed manual just click here."
 let linkTextWithColor = "click here"

 let range = (text as NSString).rangeOfString(linkTextWithColor)

 let attributedString = NSMutableAttributedString(string:text)
 attributedString.addAttribute(NSForegroundColorAttributeName, value: UIColor.redColor() , range: range)

 self.helpText.attributedText = attributedString

self.helpText is a UILabel outlet.

answered Jan 03 '16 at 12:45

Chris

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Oh Chris, u are my hero. I am searching for this exactly code block for a long time. – Pan Mluvčí Aug 10 '16 at 10:10
@chris . I want to change nsmutableattributed string in textview ,is that possible – Uma Madhavi Mar 13 '17 at 06:48
it's work for single word.but in my string there are multiple word it's color change but then i write after that red color word that word's color is also red.so can you give any solution if you have. – Dhaval Solanki Feb 16 '18 at 11:18

Egzon P. · Answer 4 · 2021-05-18T08:29:10.427

Swift 4.2 and Swift 5 colorise parts of the string.

A very easy way to use NSMutableAttributedString while extending the String. This also can be used to colourize more than one word in the whole string.

import UIKit

extension String {
    func attributedStringWithColor(_ strings: [String], color: UIColor, characterSpacing: UInt? = nil) -> NSAttributedString {
        let attributedString = NSMutableAttributedString(string: self)
        for string in strings {
            let range = (self as NSString).range(of: string)
            attributedString.addAttribute(NSAttributedString.Key.foregroundColor, value: color, range: range)
        }

        guard let characterSpacing = characterSpacing else {return attributedString}

        attributedString.addAttribute(NSAttributedString.Key.kern, value: characterSpacing, range: NSRange(location: 0, length: attributedString.length))

        return attributedString
    }
}

Now you can use globally at any viewcontroller you want:

let attributedWithTextColor: NSAttributedString = "Doc, welcome back :)".attributedStringWithColor(["Doc", "back"], color: UIColor.black)

myLabel.attributedText = attributedWithTextColor

score 11 · Answer 5 · answered Jan 11 '17 at 10:49

11

Answer is already given in previous posts but i have a different way of doing this

Swift 3x :

var myMutableString = NSMutableAttributedString()

myMutableString = NSMutableAttributedString(string: "Your full label textString")

myMutableString.setAttributes([NSFontAttributeName : UIFont(name: "HelveticaNeue-Light", size: CGFloat(17.0))!
        , NSForegroundColorAttributeName : UIColor(red: 232 / 255.0, green: 117 / 255.0, blue: 40 / 255.0, alpha: 1.0)], range: NSRange(location:12,length:8)) // What ever range you want to give

yourLabel.attributedText = myMutableString

Hope this helps anybody!

answered Jan 11 '17 at 10:49

Anurag Sharma

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@UmaMadhavi What is your requirement exactly? – Anurag Sharma Mar 16 '17 at 05:47
I want to change font size & font color in textview. I am getting it in nsmutableattributedstring. – Uma Madhavi Mar 16 '17 at 07:42
@UmaMadhavi check out this [link1](http://stackoverflow.com/questions/31647653/bold-part-of-string-in-uitextview-swift) and [link2](http://stackoverflow.com/questions/40149122/how-to-change-color-of-text-stirngs-inside-uitextview-in-swift3). It may be helpful! – Anurag Sharma Mar 16 '17 at 09:19
Crashes if font isn't available. – SafeFastExpressive May 12 '20 at 22:53

score 10 · Answer 6 · answered Sep 22 '16 at 15:10

Chris' answer was a great help to me, so I used his approach and turned into a func that I can reuse. This let's me assign a color to a substring while giving the rest of the string another color.

static func createAttributedString(fullString: String, fullStringColor: UIColor, subString: String, subStringColor: UIColor) -> NSMutableAttributedString
{
    let range = (fullString as NSString).rangeOfString(subString)
    let attributedString = NSMutableAttributedString(string:fullString)
    attributedString.addAttribute(NSForegroundColorAttributeName, value: fullStringColor, range: NSRange(location: 0, length: fullString.characters.count))
    attributedString.addAttribute(NSForegroundColorAttributeName, value: subStringColor, range: range)
    return attributedString
}

score 8 · Answer 7 · edited May 15 '18 at 08:44

8

Swift 4.1

NSAttributedStringKey.foregroundColor

for example if you want to change font in NavBar:

self.navigationController?.navigationBar.titleTextAttributes = [ NSAttributedStringKey.font: UIFont.systemFont(ofSize: 22), NSAttributedStringKey.foregroundColor: UIColor.white]

edited May 15 '18 at 08:44

pacification

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answered May 10 '18 at 14:27

swift2geek

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score 6 · Answer 8 · edited Jun 20 '20 at 09:12

You can use this extension I test it over

swift 4.2

import Foundation
import UIKit

extension NSMutableAttributedString {

    convenience init (fullString: String, fullStringColor: UIColor, subString: String, subStringColor: UIColor) {
           let rangeOfSubString = (fullString as NSString).range(of: subString)
           let rangeOfFullString = NSRange(location: 0, length: fullString.count)//fullString.range(of: fullString)
           let attributedString = NSMutableAttributedString(string:fullString)
           attributedString.addAttribute(NSAttributedStringKey.foregroundColor, value: fullStringColor, range: rangeOfFullString)
           attributedString.addAttribute(NSAttributedStringKey.foregroundColor, value: subStringColor, range: rangeOfSubString)

           self.init(attributedString: attributedString)
   }

}

Sarabjit Singh · Answer 9 · 2017-01-02T04:09:37.943

4

Swift 2.2

var myMutableString = NSMutableAttributedString()

myMutableString = NSMutableAttributedString(string: "1234567890", attributes: [NSFontAttributeName:UIFont(name: kDefaultFontName, size: 14.0)!])

myMutableString.addAttribute(NSForegroundColorAttributeName, value: UIColor(red: 0.0/255.0, green: 125.0/255.0, blue: 179.0/255.0, alpha: 1.0), range: NSRange(location:0,length:5))

self.lblPhone.attributedText = myMutableString

edited Jan 02 '17 at 04:09

answered Oct 13 '16 at 09:01

Sarabjit Singh

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I get an error when I do this. I think you want this without `.CGColor`. – Bjorn Roche Dec 29 '16 at 03:30
@SarabjitSingh. how can this is possible for textview – Uma Madhavi Mar 15 '17 at 13:18
@UmaMadhavi ... You just need to add self.textView.attributedText = myMutableString ..... It will work... – Sarabjit Singh Mar 16 '17 at 10:57

score 4 · Answer 10 · answered Oct 07 '17 at 12:14

4

Easiest way to do label with different style such as color, font etc. is use property "Attributed" in Attributes Inspector. Just choose part of text and change it like you want

answered Oct 07 '17 at 12:14

jMelvins

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Suposing you're not changing the strings programatically – Alejandro Cumpa Jul 20 '18 at 01:30

score 4 · Answer 11 · answered Apr 26 '18 at 10:39

Based on the answers before I created a string extension

extension String {

func highlightWordsIn(highlightedWords: String, attributes: [[NSAttributedStringKey: Any]]) -> NSMutableAttributedString {
     let range = (self as NSString).range(of: highlightedWords)
     let result = NSMutableAttributedString(string: self)

     for attribute in attributes {
         result.addAttributes(attribute, range: range)
     }

     return result
    }
}

You can pass the attributes for the text to the method

Call like this

  let attributes = [[NSAttributedStringKey.foregroundColor:UIColor.red], [NSAttributedStringKey.font: UIFont.boldSystemFont(ofSize: 17)]]
  myLabel.attributedText = "This is a text".highlightWordsIn(highlightedWords: "is a text", attributes: attributes)

score 4 · Answer 12 · answered May 24 '18 at 08:05

Swift 4.1

I have changed from this In Swift 3

let str = "Welcome "
let welcomeAttribute = [ NSForegroundColorAttributeName: UIColor.blue()]
let welcomeAttrString = NSMutableAttributedString(string: str, attributes: welcomeAttribute)

And this in Swift 4.0

let str = "Welcome "
let welcomeAttribute = [ NSAttributedStringKey.foregroundColor: UIColor.blue()]
let welcomeAttrString = NSMutableAttributedString(string: str, attributes: welcomeAttribute)

to Swift 4.1

let str = "Welcome "
let welcomeAttribute = [ NSAttributedStringKey(rawValue: NSForegroundColorAttributeName): UIColor.blue()]
let welcomeAttrString = NSMutableAttributedString(string: str, attributes: welcomeAttribute)

Works fine

This is changing the entire string? This is the most readable to me, but Is there a way to change only specific words within the string like the OP asked. — Moondra, Aug 20 '18 at 00:20

score 3 · Answer 13 · answered Nov 06 '18 at 09:11

swift 4.2

    let textString = "Hello world"
    let range = (textString as NSString).range(of: "world")
    let attributedString = NSMutableAttributedString(string: textString)

    attributedString.addAttribute(NSAttributedStringKey.foregroundColor, value: UIColor.red, range: range)
    self.textUIlable.attributedText = attributedString

Davender Verma · Answer 14 · 2019-01-01T09:37:22.003

3

This might be work for you

let main_string = " User not found,Want to review ? Click here"
    let string_to_color = "Click here"

    let range = (main_string as NSString).range(of: string_to_color)

    let attribute = NSMutableAttributedString.init(string: main_string)
    attribute.addAttribute(NSAttributedStringKey.foregroundColor, value: UIColor.blue , range: range)

    lblClickHere.attributedText = attribute

edited Jan 01 '19 at 09:37

answered Jan 01 '19 at 07:55

Davender Verma

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While this code snippet may be the solution, [including an explanation](//meta.stackexchange.com/questions/114762/explaining-entirely-‌code-based-answers) really helps to improve the quality of your post. Remember that you are answering the question for readers in the future, and those people might not know the reasons for your code suggestion. – HMD Jan 01 '19 at 08:16

score 3 · Answer 15 · answered Jan 29 '20 at 17:26

With this simple function you can assign the text and highlight the chosen word.

You can also change the UITextView to UILabel, etc.

func highlightBoldWordAtLabel(textViewTotransform: UITextView, completeText: String, wordToBold: String){
    textViewToTransform.text = completeText
    let range = (completeText as NSString).range(of: wordToBold)
    let attribute = NSMutableAttributedString.init(string: completeText)

    attribute.addAttribute(NSAttributedString.Key.font, value: UIFont.boldSystemFont(ofSize: 16), range: range)
    attribute.addAttribute(NSAttributedString.Key.foregroundColor, value: UIColor.black , range: range)
    textViewToTransform.attributedText = attribute
}

cgeek · Answer 16 · 2018-09-07T06:38:33.643

For everyone who are looking for "Applying specific color to multiple words in text", we can do it using NSRegularExpression

 func highlight(matchingText: String, in text: String) {
    let attributedString  = NSMutableAttributedString(string: text)
    if let regularExpression = try? NSRegularExpression(pattern: "\(matchingText)", options: .caseInsensitive) {
        let matchedResults = regularExpression.matches(in: text, options: [], range: NSRange(location: 0, length: attributedString.length))
        for matched in matchedResults {
             attributedString.addAttributes([NSAttributedStringKey.backgroundColor : UIColor.yellow], range: matched.range)

        }
        yourLabel.attributedText = attributedString
    }
}

Reference link : https://gist.github.com/aquajach/4d9398b95a748fd37e88

Is it possible to use your code in MacOS cocoa app? I tried to use it in my cocoa project, but there's no .attributedText in cocoa NSTextView. — CaOs433, Dec 03 '18 at 20:10

score 2 · Answer 17 · answered Aug 05 '20 at 10:12

You can use as simple extension

extension String{

func attributedString(subStr: String) -> NSMutableAttributedString{
    let range = (self as NSString).range(of: subStr)
    let attributedString = NSMutableAttributedString(string:self)
    attributedString.addAttribute(NSAttributedString.Key.foregroundColor, value: UIColor.red , range: range)
    
    return attributedString
  }
}

myLable.attributedText = fullStr.attributedString(subStr: strToChange)

score 2 · Answer 18 · answered Jan 30 '21 at 09:29

This extension works well when configuring the text of a label with an already set default color.

public extension String {
    func setColor(_ color: UIColor, ofSubstring substring: String) -> NSMutableAttributedString {
        let range = (self as NSString).range(of: substring)
        let attributedString = NSMutableAttributedString(string: self)
        attributedString.addAttribute(NSAttributedString.Key.foregroundColor, value: color, range: range)
        return attributedString
    }
}

For example

let text = "Hello World!"
let attributedText = text.setColor(.blue, ofSubstring: "World")

let myLabel = UILabel()
myLabel.textColor = .white
myLabel.attributedText = attributedText

score 1 · Answer 19 · edited Nov 06 '18 at 09:37

1

To change color of the font colour, first select attributed instead of plain like in the image below

You then need to select the text in the attributed field and then select the color button on the right-hand side of the alignments. This will change the color.

edited Nov 06 '18 at 09:37

saurabh

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answered Aug 30 '18 at 00:33

Kingsley Mitchell

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Ashish Chauhan · Answer 20 · 2018-09-02T18:08:23.527

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Super easy way to do this.

let text = "This is a colorful attributed string"
let attributedText = 
NSMutableAttributedString.getAttributedString(fromString: text)
attributedText.apply(color: .red, subString: "This")
//Apply yellow color on range
attributedText.apply(color: .yellow, onRange: NSMakeRange(5, 4))

For more detail click here: https://github.com/iOSTechHub/AttributedString

edited Sep 02 '18 at 18:08

answered Sep 02 '18 at 17:54

Ashish Chauhan

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Excellent, thank you. After implementing the class referenced from the link on GitHub this did exactly what I was looking for. – Dominick Oct 29 '20 at 00:33

score 1 · Answer 21 · answered Nov 16 '18 at 11:09

You can use this method. I implemented this method in my common utility class to access globally.

func attributedString(with highlightString: String, normalString: String, highlightColor: UIColor) -> NSMutableAttributedString {
    let attributes = [NSAttributedString.Key.foregroundColor: highlightColor]
    let attributedString = NSMutableAttributedString(string: highlightString, attributes: attributes)
    attributedString.append(NSAttributedString(string: normalString))
    return attributedString
}

score 0 · Answer 22 · answered May 18 '17 at 19:30

If you are using Swift 3x and UITextView, maybe the NSForegroundColorAttributeName won't work (it didn't work for me no matter what approach I tried).

So, after some digging around I found a solution.

//Get the textView somehow
let textView = UITextView()
//Set the attributed string with links to it
textView.attributedString = attributedString
//Set the tint color. It will apply to the link only
textView.tintColor = UIColor.red

score 0 · Answer 23 · answered Feb 06 '19 at 13:53

You need to change textview parameters, not parameters of attributed string

textView.linkTextAttributes = [
        NSAttributedString.Key.foregroundColor: UIColor.red,
        NSAttributedString.Key.underlineColor: UIColor.red,
        NSAttributedString.Key.underlineStyle: NSUnderlineStyle.single.rawValue
    ]

score 0 · Answer 24 · answered Mar 04 '19 at 18:50

0

Please check cocoapod Prestyler:

Prestyler.defineRule("$", UIColor.orange)
label.attributedText = "This $text$ is orange".prestyled()

answered Mar 04 '19 at 18:50

Kruiller

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score 0 · Answer 25 · answered May 11 '20 at 16:39

extension String{
// to make text field mandatory * looks
mutating func markAsMandatoryField()-> NSAttributedString{

    let main_string = self
    let string_to_color = "*"
    let range = (main_string as NSString).range(of: string_to_color)
    print("The rang = \(range)")
    let attribute = NSMutableAttributedString.init(string: main_string)
    attribute.addAttribute(NSAttributedString.Key.foregroundColor, value: UIColor.rgbColor(red: 255.0, green: 0.0, blue: 23.0) , range: range)
     return attribute
}

}

use EmailLbl.attributedText = EmailLbl.text!.markAsMandatoryField()

Changing specific text's color using NSMutableAttributedString in Swift

25 Answers25

Swift 4.1

swift 4.2

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