Info: Avoid ws_clipchildren and ActiveX Control painting Problems

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For more information about the MFC container methods, see common examples of the ATL container methods.

Summary

For Windows, in order to avoid the re-painting problem, it is used as the parent ActiveX control. In the local container, the ws_clipchildren window style must be used.

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More information

When the ws_clipchildren style exclusion area is drawn in the parent window by the Child window:

Http://msdn.microsoft.com/library/psdk/winui/windows_2v90.htm (http://msdn.microsoft.com/library/psdk/winui/windows_2v90.htm)

The style must be used for the parent window object instead of being output by the local object. For Microsoft basic class (MFC) Ole (and ActiveDirectory) Documentation containers, the Framework implicitly sets the style during local activation. However, the style must be explicitly added. In other cases, local activation is involved. This is usually from the perspective of the MFC and the Active Template Library (ATL) container, when carrying ActiveX controls.

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MFC container Methods

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For ActiveX Control bearing (including cview and cdialog), you can add the style of the MFC cwnd derived class by adding a rewrite for the virtual precreatewindow () function and modifying the precreatewindow! Alink (settings. For example, precreatewindow will show the appearance in the cview derived class: BOOL CMyView::PreCreateWindow(CREATESTRUCT& cs){// Add the WS_CLIPCHILDREN style to avoid repaint problems:cs.style |= WS_CLIPCHILDREN;return CView::PreCreateWindow(cs);}

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In the dialog box Editor, On the Style tab, you can add the ws_clipchildren style to the cdialog derived class by cutting the child level.

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About the ATL container Method

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For the container window ws_clipchildren style originating from csf-wimpl, the window feature can be specified. The ccontrolwintraits class of the cwindowimpl derived class does not include the default features specified in the ws_clipchildren style by default. For the ATL window class and window features, see the following Microsoft Web page: ATL 3.0 window class: An Introduction) subtopic uses window properties to specify a style (: http://msdn.microsoft.com/library/techart/atlwindow.htm#atlwindow_topic13 (http://msdn.microsoft.com/library/techart/atlwindow.htm#atlwindow_topic13)

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For an ATL-based dialog box, the caxdialogimpl base class is not derived from cwindowimpl, so it does not have these features. You cannot specify caxdialogimpl or custom cwintraits. You can add the ws_clipchildren style through the style tab in the dialog box editor.

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Common Methods of MFC and ATL

•	If the window uses cwnd: Create (for MFC) or cwindow: Create (for ATL), you are creating a clear ws_clipchildren style specified by the dwstyle parameter.
•	For an MFC window or cwindow: modifystyle, the style is dynamically modified for an ATL window. Once the window has been created and has a valid hwnd, you can use cwnd: modifystyle.

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Reference

Cwnd: precreatewindow http://msdn.microsoft.com/library/devprods/vs6/visualc/vcmfc/_mfc_cwnd.3a3a.precreatewindow.htm (http://msdn.microsoft.com/library/devprods/vs6/visualc/vcmfc/_mfc_cwnd.3a3a.precreatewindow.htm) cwnd: Create http://msdn.microsoft.com/library/devprods/vs6/visualc/vcmfc/_mfc_cwnd.3a3a.create.htm (http://msdn.microsoft.com/library/devprods/vs6/visualc/vcmfc/_mfc_cwnd.3a3a.create.htm) cwindow: Create http://msdn.microsoft.com/library/devprods/vs6/visualc/vcmfc/vcrefcwindowcreate.htm (http://msdn.microsoft.com/library/devprods/vs6/visualc/vcmfc/vcrefcwindowcreate.htm) cwnd: modifystyle http://msdn.microsoft.com/library/devprods/vs6/visualc/vcmfc/_mfc_cwnd.3a3a.modifystyle.htm (http://msdn.microsoft.com/library/devprods/vs6/visualc/vcmfc/_mfc_cwnd.3a3a.modifystyle.htm) cwindow: modifystyle http://msdn.microsoft.com/library/devprods/vs6/visualc/vcmfc/_atl_cwindow.3a3a.modifystyle.htm (http://msdn.microsoft.com/library/devprods/vs6/visualc/vcmfc/_atl_cwindow.3a3a.modifystyle.htm) for specific examples of correct painting, see the following Microsoft Knowledge Base Article:

220021 (http://support.microsoft.com/kb/220021/EN-US/) BUG: The chtmlview is not drawn correctly in the app MDI Application Wizard

The container window chtmlview acts as the Microsoft webbrowser control:

Http://msdn.microsoft.com/workshop/browser/webbrowser/WebBrowser.asp (http://msdn.microsoft.com/workshop/browser/webbrowser/WebBrowser.asp)

(C) Microsoft Corporation 2000 reserves all rights. Writer S. Ganesh, Microsoft Corporation.

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The information in this article applies:

•	Microsoft ActiveX template library 3.0
•	Microsoft Foundation Class Library 4.2

 

 

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