Multiple Views for a Single Document (MDI)

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I add here the code that could be used to add multiple views to a document, in a MDI application. I usually make database applications, and I don’t want that the document to be created/destroyed by the framework, so I create the document myself (and of course I destroy it J ), and in document’s constructor I set the m_bAutoDelete flag to FALSE.

The CMyApp class contains as public member a pointer to my document. I also make document templates for all views, and I keep the pointers in CMyApp. You should have something like this in InitInstance():

m_pView1Templ=new CMultiDocTemplate( IDR_VIEW1TYPE,

RUNTIME_CLASS( CMyDoc ),

RUNTIME_CLASS( CChildFrame ),

RUNTIME_CLASS( CView1 ) );

AddDocTemplate(m_pView1Templ);

// m_pView1Templ is member of CMyApp

After you created all necessary document templates, add the following code:

// create main MDI Frame window

CMainFrame* pMainFrame = new CMainFrame;

mp_doc=new CTimeClkDoc;

mp_doc->SetTitle(“Just a demo”);

CCreateContext context;

context.m_pCurrentDoc=mp_doc;

context.m_pNewViewClass=NULL;

context.m_pNewDocTemplate=NULL;

context.m_pLastView=NULL;

context.m_pCurrentFrame=NULL;

if (!pMainFrame->LoadFrame(IDR_MAINFRAME,WS_OVERLAPPEDWINDOW |

                           FWS_ADDTOTITLE,NULL, &context ))

   return FALSE;

m_pMainWnd = pMainFrame;

This code will allow opening the application without any open view and also avoids the dialog box that asks to choose a document template. Add for each view command handlers similar with this one:

void CMyApp::OnView1()

{

   // TODO: Add your command handler code here

   CChildFrame* pFrame = new CChildFrame();

   CCreateContext context;

   context.m_pCurrentDoc=mp_doc;    //that’s the way I avoid creating

                                    //a new document every time I open

                                    //a new view

   context.m_pNewViewClass=RUNTIME_CLASS(CView1);

   context.m_pNewDocTemplate=m_pView1Templ;

   context.m_pLastView=(((CMainFrame *)m_pMainWnd)->

                        GetActiveFrame() ? ((CMainFrame *)m_pMainWnd)->

                        GetActiveFrame()->GetActiveView() : NULL);

   context.m_pCurrentFrame=((CMainFrame *)m_pMainWnd)->GetActiveFrame();

   if (!pFrame->LoadFrame(IDR_VIEW1TYPE,WS_OVERLAPPEDWINDOW |

                          FWS_PREFIXTITLE ,m_pMainWnd, &context ))return;

   pFrame->InitialUpdateFrame(mp_doc,TRUE);

}