iOS Set text range in textview UIColor
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I am looking for all the text in my text view to be gray and then the first sentence to be black. How do I set that range to black. I already have the first sentence string/range. Thank You.

        [tv setTextColor:[UIColor grayColor]];
        
        id<UITextInputTokenizer> tokenizer = tv.tokenizer;
        UITextRange *range = [tokenizer rangeEnclosingPosition:tv.beginningOfDocument
                                               withGranularity:UITextGranularitySentence
                                                   inDirection:UITextStorageDirectionForward];
        NSString *firstSentence = [tv textInRange:range];
        NSLog(@"%@",firstSentence);