DOCUMENT:Q191126 17-JUL-2001 [visualc] TITLE :PRB: Font Changes as ActiveX Control Resizes PRODUCT :Microsoft C Compiler PROD/VER:winnt:5.0,6.0 OPER/SYS: KEYWORDS:kbole kbActiveX kbMFC kbVC500 kbVC600 kbGrpDSMFCATL ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - The Microsoft Foundation Classes (MFC), used with: - Microsoft Visual C++, 32-bit Enterprise Edition, version 5.0 - Microsoft Visual C++, 32-bit Professional Edition, version 5.0 - Microsoft Visual C++, 32-bit Enterprise Edition, version 6.0 - Microsoft Visual C++, 32-bit Professional Edition, version 6.0 - Microsoft Visual C++, 32-bit Learning Edition, version 6.0 ------------------------------------------------------------------------------- SYMPTOMS ======== When you call SelectStockFont() to select a Stock font property to display text in an ActiveX control, the font of the text changes as the size of the control changes with SetWindowPos() or MoveWindow(). CAUSE ===== SelectStockFont() selects a scaled font into a device context. This causes the font size to change as the control resizes. However, the natural extent is not changed (m_rcBounds is bigger but m_cyExtent is not). As a result, the stock font doesn't scale perfectly with respect to the size of the control. RESOLUTION ========== Here are two possible workarounds for this problem: 1. Use SetControlSize() instead of SetWindowPos() or MoveWindow() to change the size of the control. 2. Replace SelectStockFont() with the following code: CFontHolder& fntHolder =InternalGetFont(); HFONT internalhFont = fntHolder.GetFontHandle(); HFONT hOldFont = (HFONT)::SelectObject(pdc->m_hDC,internalhFont); pdc->TextOut(20, 20, "Hello", 5); ::SelectObject(pdc->m_hDC,hOldFont); STATUS ====== This behavior is by design. MORE INFORMATION ================ Steps to Reproduce Behavior --------------------------- 1. Generate an MFC ActiveX control with the Control Wizard. 2. Add a Stock font property to the control. 3. Add a method called SizeControl() to the control. Call SetWindowPos() in this method to change the size of the control. For example: void CFontCtrl::SizeControl() { CRect r; GetWindowRect(&r); SetWindowPos(NULL, 0, 0, r.Width() + 100, r.Height() + 100, SWP_NOMOVE); } 4. Display a text string in the control's OnDraw() function with the Stock font property as shown here: void CFontCtrl::OnDraw(CDC* pdc, const CRect& rcBounds, const CRect& rcInvalid) { pdc->FillRect(rcBounds, CBrush::FromHandle((HBRUSH)GetStockObject(WHITE_BRUSH))); pdc->Ellipse(rcBounds); CFont* def_font = SelectStockFont(pdc); pdc->TextOut(20, 20, "Hello", 5); pdc->SelectObject(def_font); } 5. Build the control project, and then insert the control to the ActiveX Control Test Container. 6. Invoke the SizeControl() method in the ActiveX Control Test Container. The font of the text changes. Additional query words: ocx ====================================================================== Keywords : kbole kbActiveX kbMFC kbVC500 kbVC600 kbGrpDSMFCATL Technology : kbAudDeveloper kbMFC Version : winnt:5.0,6.0 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.