BUG: MFC OLE Container Support May Merge Server Menus Incorrectly (259404)

The information in this article applies to:

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

This article was previously published under Q259404

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

Create a generic MFC (MDI) Active Document Container with the MFC AppWizard.
Build and run the application, and then insert an Excel Chart object into the document. Note that the menu items are merged properly.
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.

Modification Type:	Major	Last Reviewed:	11/18/2003
Keywords:	kbBug kbContainer kbnofix KB259404