To limit max lengt of CCTexFieldTTF what should I do?

UITextField it done by

Implement the UITextFieldDelegate protocol
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {
if ([textField.text length] > MAXLENGTH) {
textField.text = [textField.text substringToIndex:MAXLENGTH-1];
return NO;
}
return YES;
}

I was try using CCTextFieldDelegate but still work strange when it's length over MAX_LENGTH.
It seem to not working with IME.

#define MAX_LENGTH = 5;

class UITextFieldDelegate: public CCTextFieldDelegate {
virtual bool onTextFieldInsertText(CCTextFieldTTF * sender, const char * text, int nLen) {
if (_calcCharCount(sender->getString()) > MAX_LENGTH)
return true;

CC_UNUSED_PARAM(sender);
CC_UNUSED_PARAM(text);
CC_UNUSED_PARAM(nLen);
return false;
}
};

Thank you.

I check it for "number input",i think it also can be check for input length.

/**
@brief If the sender doesn't want to insert the text, return true;
*/
bool CCPageIndicator::onTextFieldInsertText(CCTextFieldTTF * sender, const char * text, int nLen) {
bool isValid = false;
int intValue = atoi(text);
const char * curValueChar = sender->getString();
std::string curValueStr(curValueChar);

if (intValue >=0 && intValue<=9) {
        curValueStr.append(text);
        int curValue = atoi(curValueStr.c_str());
        if (curValue>0 && curValue <= this->getMaxPage())
    {
            isValid = true;
            curPage = curValue;
        }
    }
    return !isValid;
}

It dosen't work completely.

I was try using CCTextFieldDelegate but still work strange when it's length over 5.
It seem to not working with IME.

class UITextFieldDelegate: public CCTextFieldDelegate {
virtual bool onTextFieldInsertText(CCTextFieldTTF * sender, const char * text, int nLen) {
if (_calcCharCount(sender->getString()) > 5)
return true;

CC_UNUSED_PARAM(sender);
        CC_UNUSED_PARAM(text);
        CC_UNUSED_PARAM(nLen);
        return false;
    }
};

Ok. I got it.

'Return' button on soft keyboard does not mean 'detachIME'.
It just put '\n' character.

So I had to check '\n' character before check the length of sender->getString().

if(strcmp(text, "\n") == 0) {
sender->detachWithIME();
return true;
}