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Article: Q151894
Product(s): Microsoft C Compiler
Version(s): winnt:4.0,4.1
Operating System(s): 
Keyword(s): kbMFC kbToolbar kbToolTip kbVC400 kbVC410 kbGrpDSMFCATL kbMFCCtrlBar
Last Modified: 06-MAY-2001

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

- The Microsoft Foundation Classes (MFC), used with:
   - Microsoft Visual C++, 32-bit Editions, versions 4.0, 4.1 
-------------------------------------------------------------------------------

SYMPTOMS
========

Accessing the CToolTipCtrl for a CToolBar with CBRS_TOOLTIPS style, using
GetToolBarCtrl() and subsequently using that pointer to call GetToolTips(),
returns a NULL value.

CAUSE
=====

GetToolTips() returns the pointer to a CToolTipCtrl associated specifically with
the CToolBar. The CToolTipCtrl created for a CToolBar by setting the
CBRS_TOOLTIPS style is not specific to the CToolBar, but rather, is MFC's
CToolTipCtrl common to the entire application.

RESOLUTION
==========

The common CToolTipCtrl is kept as a part of the MFC thread state information.
To access the MFC's common CToolTipCtrl, access m_pToolTip public member of the
current thread state:

     _AFX_THREAD_STATE* pThreadState = AfxGetThreadState();
      CToolTipCtrl* pToolTip = pThreadState->m_pToolTip;

STATUS
======

This behavior is by design.

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

In order to provide ToolTip support for a CToolBar, the CBRS_TOOLTIPS style has
to be set during creation or by using CControlBar::SetBarStyle(). This style
results in the ToolBar using MFC's thread specific common CToolTipCtrl rather
than a unique one for the ToolBar. Since the ToolTip is not specific to the
ToolBar, GetToolTips() returns NULL.

Note that a CToolTipCtrl specific to a CToolBar can be created by overriding the
CToolBar::PreCreateWindow() and setting the TBSTYLE_TOOLTIPS. In this case, the
return value of GetToolTips() will be valid.

REFERENCES
==========

For additional information, please see the following article in the Microsoft
Knowledge Base:

  Q151162 PRB: CToolBarCtrl Styles Fail with CToolBar

Additional query words: 4.00 4.10

======================================================================
Keywords          : kbMFC kbToolbar kbToolTip kbVC400 kbVC410 kbGrpDSMFCATL kbMFCCtrlBar 
Technology        : kbAudDeveloper kbMFC
Version           : winnt:4.0,4.1
Issue type        : kbprb

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

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Q151894: PRB: CToolBarCtrl::GetToolTips() May Return NULL for a ToolBar