Limit Text in UITextfield using a custom keyboard in Xcode
===

I just got a custom keyboard working.  I wanted to put one last touch on the App and I can't figure it out.  I want to limit the amount of text input.  I have used the method....

    - (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
    {
    NSLog(@"user is entering numbers");
    NSUInteger newLength = [textField.text length] + [string length] - range.length;
    return (newLength > 8) ? NO : YES;
    }

But it never gets called.  I can type on my actual keyboard and the text is limited to 8.  But if I use my custom keyboard in the simulator, I can put numbers in forever.  Any idea how to get this method called from my custom keyboard?  Thanks!!