Back to For Beginners

Error in my app

For Beginners

Started by logout April 29, 2003 05:49 PM

8 comments, last by logout 20 years, 11 months ago

logout

122

Author

April 29, 2003 05:49 PM

  

class CKeeper;
class CChild
{
	public:
		virtual void Execute(int icode){}
};
class CTestClass : public CChild
{
	public:
		virtual void Execute(int icode);
};

CKeeper
{
	public:
		void Attach(CChild *cc);

	private:
		vector<CChild*> vC;
};

Now the problem comes when i want to attach CTestClass into the CKeeper class

  
void CKeeper::Attach(CChild *cc)
{
	vC.push_back(cc);
}

Later in the code i call vC->Execute(some_var); So can anyone spot the problem ? btw this is a re type, cause my original code is too long and to unclear

Miserable

606

April 29, 2003 05:51 PM

quote:Original post by logout
So can anyone spot the problem ?

What is the problem?

The Corner of Misery Artwork and writing

logout

122

Author

April 29, 2003 06:12 PM

sorry.. i did forget that

it crashes .. thats the error

micepick

122

April 29, 2003 07:26 PM

Your code looks fine. Crashes involving constructs like that are almost always caused by invalid pointers.

Have you created the class you're passing to Attach using new? If you just took the address of a static object, you may be calling Execute on something that has quietly gone out of scope and died!

Are you sure you never changed the pointer, (i.e. set it to NULL) before you passed it?

Are you sure you didn't delete the object before you passed it?

[edited by - micepick on April 29, 2003 8:29:06 PM]

Infuscare

139

April 29, 2003 07:31 PM

doesn''t the program have to have a ''main'' function? or is that just a piece of the program...?

_________________________________________
"Why, why why does everyone ask ''''why'''' when ''''how'''' is so much more fun"
-Spawn 1997

_________________________________________"You're just jelous because the voices only talk to me"

Sneftel

1,788

April 29, 2003 07:35 PM

When you run it in the debugger, what line does it crash on?

How appropriate. You fight like a cow.

logout

122

Author

April 29, 2003 07:37 PM

well the code crash on the line:
vC.push_back(cc);

is there anyway i can get a more description of the error ?
using a debuger or something ?

edit:
I tryed using the debuger and got this error:

iside the vector header file

  	size_type size() const		{	// return length of sequence		return (_Myfirst == 0 ? 0 : _Mylast - _Myfirst); // the error is on this line		}

I also got this:
Unhandled exception at 0x0041a8b6 in GfxEngine.exe: 0xC0000005: Access violation reading location 0x00000004.

[edited by - LogouT on April 29, 2003 8:42:31 PM]

micepick

122

April 29, 2003 07:41 PM

Whoa, it crashes when you push a pointer into a vector? That''s very bizarre.

Sneftel

1,788

April 29, 2003 08:10 PM

It''s not bizarre at all, if vC is not valid, which happens if ''this'' is not valid, which happens if you call Attach() on a CKeeper pointer that is NULL. Which, dollars to donuts, is what you are doing. Go down in the traceback and find out what is calling Attach on a pointer that is set to NULL, and fix it.

How appropriate. You fight like a cow.

logout

122

Author

April 30, 2003 10:51 AM

how can i ensure that i got a legal this if CKeeper is a singleton ?

[edited by - LogouT on May 1, 2003 5:51:55 PM]

Error in my app

This topic is closed to new replies.

Popular Topics

Recommended Tutorials

Error in my app

This topic is closed to new replies.

Popular Topics

Recommended Tutorials

Reticulating splines