Q133276: FIX: ClassWizard Generates Incorrect UDN_DELTAPOS Handler

Article: Q133276
Product(s): Microsoft C Compiler
Version(s): winnt:
Operating System(s): 
Keyword(s): kbwizard kbMFC KbUIDesign kbGrpDSUser kbVC500 kbVC600kbbuglist kbfixlist
Last Modified: 06-MAY-2001

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The information in this article applies to:

- The ClassWizard, used with:
   - Microsoft Visual C++ 32-bit Edition, versions 2.1, 2.2 
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SYMPTOMS
========

ClassWizard creates incorrect code for a handler for the UDN_DELTAPOS
notification message of the CSpinButtonCtrl common control.

RESOLUTION
==========

The generated handler function will look like this (assuming that the
CSpinButtonCtrl is in a dialog):

    void CAboutDlg::OnDeltaposSpin1(NMHDR* pNMHDR, LRESULT* pResult)
        {
        NM_UPDOWN;
        // TODO: Add your control notification handler code here

        *pResult = 0;
        }

Modify the code to look like this:

    void CAboutDlg::OnDeltaposSpin1(NMHDR* pNMHDR, LRESULT* pResult)
        {
        NM_UPDOWN* pUpDown = (NM_UPDOWN*)pNMHDR;

        // TODO: Add your control notification handler code here

        *pResult = 0;
        }

By typecasting the pointer to the NMHDR structure, you can access additional data
that is passed after the NMHDR.

STATUS
======

Microsoft has confirmed this to be a bug in the Microsoft products listed at the
beginning of this article. This problem was corrected in Visual C++, 32-bit
Edition, version 4.0.

REFERENCES
==========

For more information about the CSpinButtonCtrl and the up down common control,
please see the Class Library Reference in Books Online and the Win32 Software
Development Kit (SDK) documentation.

Additional query words: 2.10 3.10 ClassWizard

======================================================================
Keywords          : kbwizard kbMFC KbUIDesign kbGrpDSUser kbVC500 kbVC600 kbbuglist kbfixlist
Technology        : kbVCsearch kbAudDeveloper kbClassWizard
Version           : winnt:
Issue type        : kbbug
Solution Type     : kbfix

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