Thread: Problem with Listbox and Subclassing

The code in red is where I think the problem lies.

This is how I create the ListBox (I would specifiy "LISTBOX" in the pszType field):

Code:

void cCHILDWINDOW::Create(const char *pszType, HWND hwnd, int cx, int cy, int x, int y, DWORD dwStyle, DWORD dwExStyle)
{
	this->hParent=hwnd;
	this->hwnd=CreateWindowEx(dwExStyle, pszType, NULL, dwStyle | WS_CHILD | WS_VISIBLE, 
							x, y, cx, cy, hParent, NULL, 0, NULL);

	
	OldChildProc=(WNDPROC)SetWindowLong(this->hwnd, GWL_WNDPROC, (LONG)ChildProc);
	SendMessage(this->hwnd, WM_SETFONT, (WPARAM)GetStockObject(DEFAULT_GUI_FONT), TRUE);
}

Here is the procedure for the subclass:

Code:

LRESULT CALLBACK cCHILDWINDOW::ChildProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
	cCHILDWINDOW **TempChild;
	cLINKEDLIST<cCHILDWINDOW*> *ChildWindow=&cWINDOW::ChildWindow;

	if ( ChildWindow->Count() )
	{
		//Finds the window message was sent to
		ChildWindow->Reset();
		do
		{
			if ( hwnd==**(TempChild=ChildWindow->Node()) )
				break;
		}
		while ( ChildWindow->Next() );

		//Call the default function for default actions to happen
		CallWindowProc((*TempChild)->OldChildProc, (*TempChild)->hwnd, message, wParam, lParam);
		(*TempChild)->ProcessEvents(hwnd, message, wParam, lParam);
	}

	return 1;
}

The problem is that when I try to get the listbox count it always says its one. Even with the CallWindowProc included.

Does anyone know why this is happening?

Thanks

Try the following:

Code:

	if ( ChildWindow->Count() )
	{
		//Finds the window message was sent to
		ChildWindow->Reset();
		do
		{
			if ( hwnd==**(TempChild=ChildWindow->Node()) )
				break;
		}
		while ( ChildWindow->Next() );


		(*TempChild)->ProcessEvents(hwnd, message, wParam, lParam);
	}

	return CallWindowProc((*TempChild)->OldChildProc,hwnd, message, wParam, lParam);;

CallWindowProc needs to be called every time, not just when your if statement evaluates to true.

Thanks bithub! That worked

Joe