PRB: DoSuperclassPaint Calls WM_PRINT for Windows 95 (147426)
The information in this article applies to:
- The Microsoft Foundation Classes (MFC), when used with:
- Microsoft Visual C++, 32-bit Professional Edition 4.0
- Microsoft Visual C++, 32-bit Learning Edition 4.0
This article was previously published under Q147426 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.
| Modification Type: | Major | Last Reviewed: | 11/18/2003 |
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| Keywords: | kbCtrl kbprb KB147426 |
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