Cursor move Automatically

/ wen cursor automatically go to next uitextfields*********
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
    NSString *strPassword = [textField.text stringByReplacingCharactersInRange:range withString:string];
    if( [strPassword length] > 0 ){
        textField.text = string;
        UIResponder* nextResponder = [textField.superview viewWithTag:(textField.tag + 1)];
        if (nextResponder) {
            [nextResponder becomeFirstResponder];
        }
        return NO;
    }
    return YES;
}