Using `textField:shouldChangeCharactersInRange:`, how do I get the text including the current typed character?

user_265961 0
Viewed 95478

I'm using the code below to try and have textField2's text content get updated to match textField1's whenever the user types in textField1.

- (BOOL) textField: (UITextField *)theTextField shouldChangeCharactersInRange: (NSRange)range replacementString: (NSString *)string {    
  if (theTextField == textField1){    
     [textField2 setText:[textField1 text]];    
  }
}

However, the output I observe is that...

textField2 is "12", when textField1 is "123"

textField2 is "123", when textField1 is "1234"

... when what I want is:

textField2 is "123", when textField1 is "123"

textField2 is "1234", when textField1 is "1234"

What am I doing wrong?

uitextfield objective-c ios
10 Answers

-shouldChangeCharactersInRange gets called before text field actually changes its text, that's why you're getting old text value. To get the text after update use:

[textField2 setText:[textField1.text stringByReplacingCharactersInRange:range withString:string]];
user_1373500

Instead of using the UITextFieldDelegate, try to use "Editing Changed" event of UITextField.

user_2505290

In Swift(4), without NSString (pure Swift):

func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {

    if let textFieldString = textField.text, let swtRange = Range(range, in: textFieldString) {

        let fullString = textFieldString.replacingCharacters(in: swtRange, with: string)

        print("FullString: \(fullString)")
    }

    return true
}

As an extension:

extension UITextField {

    func fullTextWith(range: NSRange, replacementString: String) -> String? {

        if let fullSearchString = self.text, let swtRange = Range(range, in: fullSearchString) {

            return fullSearchString.replacingCharacters(in: swtRange, with: replacementString)
        }

        return nil
    }
}

// Usage:

func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {

    if let textFieldString = textField.fullTextWith(range: range, replacementString: string) {
        print("FullString: \(textFieldString)")
    }

    return true
}
user_32765180

This is the code you need,

if ([textField isEqual:self.textField1])
  textField2.text = [textField1.text stringByReplacingCharactersInRange:range withString:string];
user_2507280
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