Re: Adding text to a listbox from main frame

I am a new poster here, so I hope this is the correct group to put this
in...

I am a beginner to VC++, and I'm trying to accomplish something that
seems like it should be simple. I have a main frame that I've added a
child dialog to, called TabCtrlHolder, which acts as a holder for the
various pages in my tab control.

I then have 6 pages that I can switch through with tab control. On one
of these pages, I have a listbox that I need to add data to every time
an event occurs. But I can't seem to access the listbox! I've tried
the following:

classWithListBox cwlb;

mainFrm: mainFrm()
{
}

void mainFrm::OnClientStatus(DWORD status)
{
         CString msg;
         msg.Format("{%02d:%02d:%02d} Connection
Established",theTime.GetHour(),
            theTime.GetMinute(),theTime.GetSecond());
         // add the string to the listbox
         vc.m_clientLB.AddString(msg);
}

and I get an assertion error:

    ASSERT(::IsWindow(m_hWnd));

I assume that the problem I'm having is that cwlb is not actually
assigned to any real object yet...which may make this more of a
fundamental C++ question than an MFC question. But how would I get the
main frame to recognize that I am trying to access the members of my
tab control, of which there are no references within the actual main
frame class?

I appreciate the help and apologize for my ignorance.

-Matt