DOCUMENT:Q145864  06-MAY-2001  [visualc]
TITLE   :PRB: Returning FALSE from OnSetActive Doesn't Set Correct Tab
PRODUCT :Microsoft C Compiler
PROD/VER:winnt:
OPER/SYS:
KEYWORDS:kbcode kbMFC kbPropSheet KbUIDesign kbVC400 kbGrpDSMFCATL

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

 - The Microsoft Foundation Classes (MFC), used with:
    - Microsoft Visual C++ 32-bit Edition, version 4.0 
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SYMPTOMS
========

To disallow activation of a CPropertyPage, you are supposed to be able to return
FALSE from OnSetActive(). This causes the next page to be activated instead of
the one the user clicked. This works fine as long as there is a next page and
the next page returns TRUE from OnSetActive(). If the next page is not
available, the tab you clicked will be activated but the page still points to
the previous one. In other words, the tab that is activated doesn't match the
page. Furthermore, the OnSetActive() function is called an additional ten times.

CAUSE
=====

Returning FALSE from OnSetActive() prompts MFC to return a -1 from
PSN_SETACTIVE. The PropertySheet control doesn't handle this correctly when the
next tab is not available.

RESOLUTION
==========

In OnSetActive(), post a message of PSM_SETCURSEL to activate a different page.
Then return TRUE.

Sample Code
-----------

   // CPage1 is derived from CPropertyPage
   BOOL CPage1::OnSetActive()
   {
      // always activate the first page instead
      GetParent()->PostMessage (PSM_SETCURSEL, 0);
      return CPropertyPage::OnSetActive();
   }

   /* Compile options needed: default
   */ 

STATUS
======

This behavior is by design.

Additional query words: 4.00 CPropertySheet CPropertyPage PSN_SETACTIVE OnSetActive FALSE

======================================================================
Keywords          : kbcode kbMFC kbPropSheet KbUIDesign kbVC400 kbGrpDSMFCATL 
Technology        : kbAudDeveloper kbMFC
Version           : winnt:
Issue type        : kbprb

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

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