Re: Inheritance and MFC

From:

"Nobody" <Nobody@yahoo.com>

Newsgroups:

microsoft.public.vc.mfc

Date:

Tue, 3 Jul 2007 17:36:28 -0700

Message-ID:

<eN#7eNdvHHA.4796@TK2MSFTNGP04.phx.gbl>

Hi Tom,

You didn't post any of the code from your grid object,

I posted what was relevant.

if it is a control or displays anything I'll be it is already derived =

from or contains a CWnd at some point.
It does not.

Is this an object you created...

Yes.

I guess that is what I am doing.
I am trying to create a control.
It is a control, but does not contain any controls.
I am trying to add controls to my control. i.e. Scrollbars

I noticed that the more I use the grid object, the more I have to keep =
adding scroll bars for pan, zoom, etc.
So, my idea was to make a CWnd GridSB Class that implements Scrollbars.
That class inherits from the Grid CObject class.
Then, I can leave the scroll bars inside of the CGrid Object, instead of =
Creating scroll bars each time.

This is basically what I have.

CGrid : public CObject
{
   //Bunch of stuff
}

CGridSB: public CGrid, public CWnd
{
    CScrollbar sb;
    CreateScrollbars();
    SetScreenRect(){ PositionScrollbars(); }
}

CView::OnDraw()
{
    CGridSB sb;
    sb.SetScreenRect(Rect);
    sb.OnDraw(pDC);
}

Regards,
"Tom Serface" <tom.nospam@camaswood.com> wrote in message =
news:E1F2C36C-392C-49C3-B5A5-BD255AFAA8A4@microsoft.com...

You didn't post any of the code from your grid object, but if it is a
control or displays anything I'll be it is already derived from or =

contains

a CWnd at some point. Is this an object you created or one you can =

point us

to on the web so we could get a better look at what it's doing?

Tom

"Nobody" <Nobody@yahoo.com> wrote in message
news:ONG3vdVvHHA.3772@TK2MSFTNGP05.phx.gbl...
Hi,

I have a grid object. The Grid Object inherits from CObject.
There are no controls and I was thinking about adding some. Zoom, Pan, =

etc.

So, I have extantiated a new class that inherits from CGrid and CWnd.
class CGridSB : public CGrid, public CWnd

Now, I would like to add some controls to the Grid Object.
The problem is that the controls needs an m_hWnd
I am not sure what to do?

VERIFY(c_sbHZoom.Create(
     SBS_VERT | SBS_RIGHTALIGN | WS_CHILD |WS_BORDER,
  Rect,
  this,
  1234)
);

_AFXWIN_INLINE void CScrollBar::ShowScrollBar(BOOL bShow)
{ ASSERT(::IsWindow(m_hWnd)); ::ShowScrollBar(m_hWnd, SB_CTL, bShow); =

}

I understand that the CGridSB oject needs to handle the Scrollbar =

messages,

so I need a message map
and perphaps a DECLARE_DYNCREATE along with an IMPLEMENT_DYNCREATE =

member.

I just need to get past the m_hWnd error.

Thanks for your help,