Class Member Callback

DrDeath (3)
Hi, im new programming in C++ and i got a problem with my 2 classes. First class was supposed to keep some data as well as calling a specific function member from a specific class when the function member "draw" was called. That specific function member should be defined only by the second class through "hDraw" that would be a private member except for the second class, of course. But when i try to call "hDraw" from the second class constructor, an error with Access Violation appears. What should i do? Below is my full code

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".h"

typedef struct
{
	short x;
	short y;
	short z;
} STR0, *PSTR0;

typedef struct
{
	short x;
	short y;
	short h;
	short w;
} STR1, *PSTR1;

typedef char *STR2;

class CLS1;

class CLS0
{
	public:
		CLS0(void)
		{
			pos.x = 0;
			pos.y = 0;
			pos.z = 0;
				
			rct.x = 0;
			rct.y = 0;
			rct.h = 0;
			rct.w = 0;

			pid = "NULL\0";

			drw = false;
			cmd = false;
			hdw = false;
		}

		STR0 getPosition(void)
		{
			return pos;
		}

		void setPosition(STR0 p)
		{
			pos.x = p.x;
			pos.y = p.y;
			pos.z = p.z;
		}

		STR1 getSize(void)
		{
			return rct;
		}

		void setSize(STR1 p)
		{
			rct.x = p.x;
			rct.y = p.y;
			rct.h = p.h;
			rct.w = p.w;
		}

		STR2 getName(void)
		{
			return pid;
		}

		void setName(STR2 p)
		{
			pid = p;
		}

		void draw(bool p)
		{
			drw = true;

			if (p) cmd = true;
			else cmd = false;

			if (hdw)
				(ph->*hw)(pos,rct,pid,cmd);
		}

		friend CLS1;

	private:
		void hDraw(void (CLS1::*h)(STR0,STR1,STR2,bool), CLS1 *hp)
		{
			ph = hp;
			hw = h;
			hdw = true;
		}

		STR0 pos;
		STR1 rct;
		STR2 pid;
		bool drw;
		bool cmd;
		bool hdw;
		CLS1 *ph;
		void (CLS1::*hw)(STR0,STR1,STR2,bool);
};

typedef CLS0 *PCLS0;

class CLS1
{
	public:
		CLS1()
		{
			conf.hDraw(&CLS1::buildFrame, this);
		}

	public:
		friend CLS0;
		CLS0 conf;

	private:
		void buildFrame(STR0 p1, STR1 p2, STR2 p3, bool p4)
		{
			std::cout << "Complete" << std::endl;
		}
};

typedef CLS1 *PCLS1;


".cpp"

int main(void) 
{
	CLS1 win
	win.conf.draw(true);

	system("PAUSE");

	return 0;
}
Last edited on
Bazzy (6281)
Line 87: friend CLS1; add 'class' : friend class CLS1;
DrDeath (3)
yes indeed.... now works... thx
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