DOCUMENT:Q141499 02-JUL-2002 [visualc] TITLE :VWRPLC32 Replacing a View in a CMDIChildWnd Window PRODUCT :Microsoft C Compiler PROD/VER::4.0,4.1,4.2,5.0,6.0 OPER/SYS: KEYWORDS:kbcode kbfile kbSample kbDocView kbMDI kbMFC kbVC400 kbVC500 kbVC600 kbGrpDSMFCATL ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - The Microsoft Foundation Classes (MFC), used with: - Microsoft Visual C++, 32-bit Editions, versions 4.0, 4.1, 4.2, 5.0, 6.0 ------------------------------------------------------------------------------- This is the 32-bit version of this sample. SUMMARY ======= The VWRPLC32 sample demonstrates how, in a Multidocument Interface (MDI) application, a programmer can write a ReplaceView() member function for a CMDIChildWnd-derived class. NOTE: The following samples, which also replace various views, exist: SPLIT32 (SDI) COLLECT (MDI) ENROLL (SDI) VSWAP32 (SDI) The following files are available for download from the Microsoft Download Center: Visual C++ 6.0: DownloadDownload Vwrplc32.exe now (http://download.microsoft.com/download/vc60pro/Sample/2/WIN98/EN-US/Vwrplc32.exe) For additional information about how to download Microsoft Support files, click the following article number to view the article in the Microsoft Knowledge Base: Q119591 How to Obtain Microsoft Support Files from Online Services Microsoft scanned this file for viruses. Microsoft used the most current virus-detection software that was available on the date that the file was posted. The file is stored on secure servers that prevent any unauthorized changes to the file. Visual C++ .NET: DownloadDownload Vwrplc32vcnet.exe now (http://download.microsoft.com/download/VisualStudioNET/sample/1.19/WIN98MeXP/EN-US/Vwrplc32vcnet.exe) Release Date: June 26, 2002 For additional information about how to download Microsoft Support files, click the following article number to view the article in the Microsoft Knowledge Base: Q119591 How to Obtain Microsoft Support Files from Online Services Microsoft scanned this file for viruses. Microsoft used the most current virus-detection software that was available on the date that the file was posted. The file is stored on secure servers that prevent any unauthorized changes to the file. NOTE: Use the -d option when running VWRPLC32.EXE to decompress the file and re-create the proper directory structure. MORE INFORMATION ================ The core of the sample can be found in FRAME.CPP. You will see the following function: BOOL CFrame::ReplaceView(CRuntimeClass * pViewClass) { CCreateContext context; CView * pCurrentView; // If no active view for the frame, return FALSE because // thisfunction retrieves the current document from the active // view. if ((pCurrentView=GetActiveView())==NULL) return FALSE; // If we're already displaying this kind of view, no need // to go further. if ((pCurrentView->IsKindOf(pViewClass))==TRUE) return TRUE; // Get pointer to CDocument object so that it can be used // in the creation process of the new view. CDocument * pDoc= pCurrentView->GetDocument(); // Set flag so that document will not be deleted when // view is destroyed. BOOL bAutoDelete=pDoc->m_bAutoDelete; pDoc->m_bAutoDelete=FALSE; // Delete existing view pCurrentView->DestroyWindow(); // restore flag pDoc->m_bAutoDelete=bAutoDelete; // Create new view and redraw. context.m_pNewViewClass=pViewClass; context.m_pCurrentDoc=pDoc; context.m_pNewDocTemplate=NULL; context.m_pLastView=NULL; context.m_pCurrentFrame=this; CView * pNewView = (CView *) pViewClass->CreateObject(); if (pNewView == NULL) { TRACE1("Warning: Dynamic create of view type %Fs failed\n", pViewClass->m_lpszClassName); return FALSE; } if (!pNewView->Create(NULL, NULL, AFX_WS_DEFAULT_VIEW, CRect(0,0,0,0), this, AFX_IDW_PANE_FIRST, &context)) { TRACE0("Warning: couldn't create view for frame\n"); return FALSE; // Programmer can assume FALSE return value // from this function means that there // isn't a view. } // WM_INITIALUPDATE is define in AFXPRIV.H. pNewView->SendMessage(WM_INITIALUPDATE, 0, 0); RecalcLayout(); pNewView->UpdateWindow(); SetActiveView(pNewView); return TRUE; } The function receives a pointer to CRuntimeClass object for the new view that is desired. It destroys the old view and replaces it with a new view of the same CDocument. When DestroyWindow() is called for the old view, this causes a "delete this" in the CView::PostNcDestroy() function. Also, the CView::~CView destructor calls CView::RemoveView(), which removes the view from the document's view list. REFERENCES ========== For additional information, please see the following article in the Microsoft Knowledge Base: Q102829 Replacing a View in a CMDIChildWnd Window Additional query words: MDI Vwrplc32 Vwrplc32vcnet ====================================================================== Keywords : kbcode kbfile kbSample kbDocView kbMDI kbMFC kbVC400 kbVC500 kbVC600 kbGrpDSMFCATL Technology : kbAudDeveloper kbMFC Version : :4.0,4.1,4.2,5.0,6.0 ============================================================================= 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 2002.