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ios - Limit number of characters in uitextview

I am giving a text view to tweet some string .

I am applying the following method to restrict the number of characters to 140 in length.

- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text{
   return [[textView text] length] <= 140;
}

The code is working nicely except the first condition that backspace is not working. suppose that I have reached the limit of 140 characters so that the method will give me false and the user can not insert more characters but after that when I try to delete some characters the text view behave as it is disabled .

So the question is: "How to delete characters from textview.text or re-enable the text view?"

See Question&Answers more detail:os

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- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text
{
    return textView.text.length + (text.length - range.length) <= 140;
}

This accounts for users cutting text, or deleting strings longer than a single character (ie if they select and then hit backspace), or highlighting a range and pasting strings shorter or longer than it.

Swift 4.0 Version

 func textView(_ textView: UITextView, shouldChangeTextIn range: NSRange, replacementText text: String) -> Bool {
    return textView.text.count + (text.count - range.length) <= 140
}

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