KnowledgeBase Archive

An Archive of Early Microsoft KnowledgeBase Articles

View on GitHub

Q259404: BUG: MFC OLE Container May Merge Server Menus Incorrectly

Article: Q259404
Product(s): Microsoft C Compiler
Version(s): winnt:6.0
Operating System(s): 
Keyword(s): kbole kbContainer kbMFC kbVC600bug kbDSupport kbGrpDSMFCATLkbbuglist
Last Modified: 07-MAY-2001

-------------------------------------------------------------------------------
The information in this article applies to:

- Microsoft Visual C++, 32-bit Enterprise Edition, version 6.0 
- Microsoft Visual C++, 32-bit Professional Edition, version 6.0 
- Microsoft Visual C++, 32-bit Learning Edition, version 6.0 
-------------------------------------------------------------------------------

SYMPTOMS
========

Microsoft Foundation Class Library (MFC) Active Document Container programs may
improperly merge server menus when in-place activating an Active Document
object. Top-level menu items may not appear in the expected order.

CAUSE
=====

Some Active Document Servers (such as Microsoft Excel) do not always pass a
zero-initialized array of OLEMENUGROUPWIDTHS to the container's
IOleInPlaceFrame::SetMenus function. The way in which MFC implements
IOleInPlaceFrame::SetMenus makes use of the AfxMergeMenus function, which is
used by both MFC containers and servers. When the OLEMENUGROUPWIDTHS array
contains non-zeros, the AfxMergeMenus call runs the server code path instead of
the code path for containers, which causes the menus to be merged in the wrong
order.

RESOLUTION
==========

To work around this problem, override the container's COleDocObjectItem-derived
class's OnInsertMenus function, initialize the OLEMENUGROUPWIDTHS structure with
zeros, and then call the base COleDocObjectItem::OnInsertMenus. For example:

  void CTestAppCntrItem::OnInsertMenus(CMenu* pMenuShared, LPOLEMENUGROUPWIDTHS lpMenuWidths)
  {
     memset(lpMenuWidths,0,sizeof(OLEMENUGROUPWIDTHS));
     COleDocObjectItem::OnInsertMenus(pMenuShared,lpMenuWidths);	
  }

STATUS
======

Microsoft has confirmed that this is a bug in the Microsoft products that are
listed at the beginning of this article.

MORE INFORMATION
================

Steps to Reproduce Behavior
---------------------------

1. Create a generic MFC (MDI) Active Document Container with the MFC AppWizard.

2. Build and run the application, and then insert an Excel Chart object into the
  document. Note that the menu items are merged properly.

3. Switch from the Chart tab to the Sheet tab, and note that the menus are no
  longer in the proper order.

When you click the Sheet tab, a different view of the object is displayed, which
causes a different set of menus to be displayed. This problem occurs for any MFC
container that supports more than just the File group of menu items. A
wizard-generated MDI application contains both the File and Window groups of
menus. You can also have a Window group if you add it manually. If you only have
a File group, however, the menus merge properly.

This problem does not occur in a generic SDI application, because the AppWizard
only adds the File menu group to your menu resource.

REFERENCES
==========

Chapter 22, Inside OLE 2nd Edition. Kraig Brockschmidt, Microsoft Press.

Additional query words: OLEMENUGROUPWIDTHS COleDocObjectItem codepath

======================================================================
Keywords          : kbole kbContainer kbMFC kbVC600bug kbDSupport kbGrpDSMFCATL kbbuglist
Technology        : kbVCsearch kbAudDeveloper kbVC600 kbVC32bitSearch
Version           : winnt:6.0
Issue type        : kbbug
Solution Type     : kbnofix

=============================================================================

THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY.