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Pointer undefined even thought it should be

May 30, 2015 at 3:13am
ZeHgS (37)
Hello,

I have something like this. Why is lastItem undefined? Is this not the correct syntax?

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Menu*   CreateItem() 
{
    Menu* menuPointer = new Menu;   
    //initialize values     
    return menuPointer; 
}

void AnotherFunction() 
{
    Menu* lastItem = CreateItem();
}


Thanks a lot!
Last edited on May 30, 2015 at 3:13am
May 30, 2015 at 3:34am
kong288 (245)
No idea. This works for me:

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class Menu
{
public:
	Menu(){}
	~Menu(){}
};

Menu* CreateMenu()
{
	Menu* menuPointer = new Menu;

	return menuPointer;
}

int main()
{
	Menu* menu = CreateMenu();

	return 0;
}


Maybe show more code?
May 30, 2015 at 3:51am
ZeHgS (37)
Thanks for your answer! I just figured it out, but I don't really understand why that wasn't working. The more complete context looks something like this

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Menu*   Content::CreateItem() 
{
    Menu* menuPointer = new Menu;   
    //initialize values     
    return menuPointer; 
}

void Content::CreateObject(Menu* curItem, Menu* lastItem)
{
	 lastItem = CreateItem();
	 curItem = lastItem;
}

void Content::Initialize()
{
	Menu*	curItem = 0;
	Menu*	lastItem = 0;

	while (...)
	{
		if (/*object is complete*/)
		{
			CreateObject(curItem, lastItem);
		}
		//create object little by little
	}
}


I changed

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	Menu*	curItem = 0;
	Menu*	lastItem = 0;


to
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	Menu*	curItem = new Menu;
	Menu*	lastItem = new Menu;


Why was this necessary?
May 30, 2015 at 7:22am
Gamer2015 (810)
no, it still does not work...
look at my last post in this topic: http://www.cplusplus.com/forum/beginner/165851/
May 30, 2015 at 10:58am
ZeHgS (37)
OMG, thank you so much! You were right, it only seemed to work but actually did not. It's finally working, thank you very much!
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