Using ATL to Automate an MFC Application

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1. Lets start first to make the application visible. Add a property ‘Visible’ as a VARIANT_BOOL.
   The code should look like this:

   
   
   //———————————————–
   
   // get & put_Visible
   
   //———————————————–
   
   //
   
   STDMETHODIMP
   
   CAutoATLApp::get_Visible(VARIANT_BOOL *pVal)
   
   {
   
    METHOD_PROLOGUE_ATL
   
    CWnd* pMainWnd = AfxGetMainWnd();
   
    ASSERT(pMainWnd);
   
    *pVal = pMainWnd->IsWindowVisible();
    return S_OK;
   
   }
   STDMETHODIMP
   
   CAutoATLApp::put_Visible(VARIANT_BOOL newVal)
   
   {
   
    METHOD_PROLOGUE_ATL
    CWnd* pMainWnd = AfxGetMainWnd();
   
    ASSERT(pMainWnd);
   
    pMainWnd->ShowWindow(SW_SHOW);
   
    pMainWnd->UpdateWindow();
    return S_OK;
   
   }
   
   

2. When i document i created by a client no frame or views are created. To be able to do so we must override CreateNewDocument in CMultiDocTemplate. CreateNewDocument is called from OpenDocumentFile to create a new document. But the document already exists. CrateNewDocument should therefor be altered NOT to create a document.
   Create a new class that inherites from CMultiDocTemplate and override CreateNewDocument and add a member variable CDocument* m_pDocument. CreateNewDocument should look like this:

   
   
   CDocument*
   
   CAnotherMultiDocTemplate::CreateNewDocument()
   
   {
   
    // default implementation constructs one from CRuntimeClass
   
    if (m_pDocClass == NULL)
   
    {
   
     TRACE0(“Error: you must override ”
   
            “CDocTemplate::CreateNewDocument.n”);
   
     ASSERT(FALSE);
   
     return NULL;
   
    }
   
   //———————————————–
   
   //	BdL; Document has already been created!
   
   //
   
   //	CDocument* pDocument = 
   
   //	   (CDocument*)m_pDocClass->CreateObject();
   
   //———————————————–
   
    if (m_pDocument == NULL)
   
    {
   
     TRACE1(“Warning: Dynamic create of document ”
   
            “type %hs failed.n”,
   
     m_pDocClass->m_lpszClassName);
   
     return NULL;
   
    }
    ASSERT_KINDOF(CDocument, m_pDocument);
   
    AddDocument(m_pDocument);
   
    return m_pDocument;
   
   }
   
   

   To make your life a bit more easy, add the header file
   (AnotherMultiDocTemplate.h) of the new class to stdafx.h

3. Alter in InitInstance of the application the DocumentTemplate:
   

   
   
   // CMultiDocTemplate* pDocTemplate;		
   
   // pDocTemplate = new CMultiDocTemplate(
   
   to
   
   CAnotherMultiDocTemplate* pDocTemplate;
   
   pDocTemplate = new CAnotherMultiDocTemplate(
   
   

4. Add FinalConstruct and FinalRelease to CAutoATLDoc. FinalConstruct will continue to create Frame and View. FinalRelease will the necessary cleanup.

   Add the following lines to CAutoAtlDoc.h

   
   
   HRESULT	FinalConstruct();
   
   void	FinalRelease();
   
   

   Add the following lines to CAutoAtlDoc.cpp

   
   
   HRESULT
   
   CAutoATLDoc::FinalConstruct()
   
   {
   
    METHOD_PROLOGUE_ATL
   
    CAutoATLApp* pApp = (CAutoATLApp*)AfxGetApp();
   
    ASSERT_VALID(pApp);
    // Find document template
   
    POSITION pos = pApp->GetFirstDocTemplatePosition();
   
    CAnotherMultiDocTemplate* pDocClass =
   
     (CAnotherMultiDocTemplate*)pApp->GetNextDocTemplate(pos);
    ASSERT_VALID(pDocClass);
    // Create view and frame
   
    pDocClass->m_pDocument = this;
   
    pDocClass->OpenDocumentFile(NULL, true);
    return S_OK;
   
   }
   void
   
   CAutoATLDoc::FinalRelease()
   
   {
   
    // Do will still have a View connected?
   
    // (The frame will no longer exist if the document
   
    // has been closed manually, because the OnClose
   
    // message is passed BEFORE deleting the document)
   
    POSITION pos = GetFirstViewPosition();
   
    if (pos != NULL) {
   
     // Prevent the document from deleting itself already.
   
     m_bAutoDelete = false;
   
     OnCloseDocument();
   
     m_bAutoDelete = true;
   
    }
   
   }
   
   

5. In the application override OnFileOpen, OnFileNew and OpenDocumentFile. Normally OnFileOpen and OnFileNew create a document AND the frame and view. Now the frame and view are now created in the FinalConstruct of CAutoAtlDoc.
   

   
   
   //———————————————–
   
   // 
   
   //———————————————–
   
   //
   
   void
   
   CAutoATLApp::OnFileNew()
   
   {
   
    // Dynamically create a new CFuchiaDocument.
   
    // The document will continue to create itself
   
    // in the constructor.
   
    IMPLEMENT_CREATE_DOCUMENT;
   
   }
   
   void
   
   CAutoATLApp::OnFileOpen()
   
   {
   
    // prompt the user (with all document templates)
   
    CString _lpszPathName;
   
    if (!DoPromptFileName(_lpszPathName,
   
                          AFX_IDS_OPENFILE,
   
                          OFN_HIDEREADONLY | OFN_FILEMUSTEXIST,
   
                          TRUE, NULL))
   
     return; // open cancelled
    OpenDocumentFile(_lpszPathName);
   
   }
   CDocument*
   
   CAutoATLApp::OpenDocumentFile(LPCTSTR lpszFileName)
   
   {
   
    // Dynamically create a new CFuchiaDocument.
   
    // The document will continue to create itself
   
    // in the constructor.
   
    IMPLEMENT_CREATE_DOCUMENT;
    // Open an existing document
   
    CWaitCursor wait;
   
    if ( !pDoc->OnOpenDocument( lpszFileName ) )
   
    {
   
     // Unable to open the document.
   
     TRACE( “Unable to open the document
   
     in %s at %d.n”, THIS_FILE, __LINE__ );
   
     // We must delete the document instance.
   
     pDoc->Release();
   
     return NULL;
   
    }
    // Set the document file path and name.
   
    pDoc->SetPathName(lpszFileName);
   
    return pDoc;
   
   }
   
   

6. IMPLEMENT_CREATE_DOCUMENT is a macro you can put on top in the document header file.
   

   
   
   //———————————————–
   
   // Call this MACRO when you need to create a new Document.
   
   // The document will construct itself further inside
   
   // FinalConstruct.
   
   #define IMPLEMENT_CREATE_DOCUMENT
   
    CComObject* pDoc;
   
    HRESULT hr = CComObject::CreateInstance(&pDoc);
   
    ASSERT(SUCCEEDED(hr));
   
    pDoc->InternalAddRef();
   
   //———————————————–
   
   

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