DOCUMENT:Q147426 06-MAY-2001 [visualc] TITLE :PRB: DoSuperclassPaint Calls WM_PRINT for Windows 95 PRODUCT :Microsoft C Compiler PROD/VER:winnt: OPER/SYS: KEYWORDS:kbole kbCtrl kbMFC 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 ------------------------------------------------------------------------------- SYMPTOMS ======== In some cases, you may need to take a window's custom control and subclass it with an OLE control. However, when the control is built using MFC 4.0 and being used in Windows 95, the OLE control may paint incorrectly. CAUSE ===== A typical OnDraw() handler in an OLE control that subclasses a window's custom control makes a call to DoSuperclassPaint(). In Windows 95, The MFC 4.0 implementation of DoSuperClassPaint() has been changed to send a WM_PRINT message to the custom control's window procedure instead of a WM_PAINT message. If the original custom control does not handle WM_PRINT, the OLE control will not paint correctly. RESOLUTION ========== It is necessary for the original custom control to handle the WM_PRINTCLIENT message, which is what the DefWindowProc sends in response to receiving a WM_PRINT message. The WM_PRINTCLIENT message should be handled in the same manner as the WM_PAINT message except that the calls to BeginPaint() and EndPaint() should be removed. STATUS ====== This behavior is by design. Additional query words: 4.00 ====================================================================== Keywords : kbole kbCtrl kbMFC kbVC400 kbGrpDSMFCATL Technology : kbAudDeveloper kbMFC Version : winnt: Issue type : kbprb ============================================================================= 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. Copyright Microsoft Corporation 2001.