Converting a CDialog to a CFormView

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You have just learned about CFormView.  You want to convert a dialog (perhaps your dialog from your old dialog-based app) to be a CFormView, without having to rewrite everything.

This essay is based on a couple assumptions:

• You have a blank CFormView that you want to transfer your CDialog to
• You want the same document for each CFormView

alternatively

• You have an existing document that you want to associate with a CFormView as an alternate view

By the time we are finished, you should see how we can extend this to multiple documents, views, etc.

Converting a dialog-based app to a CFormView-based SDI or MDI app

To convert a dialog-based app to an SDI or MDI CFormView-based app, first generate an app with a CFormView.  Move the projectView.h and projectView.cpp files to some other directory, and copy your oldprojectdlg.h and oldprojectdlg.cpp files over as the names proejctView.h and projectView.cpp files.

Open them up, and replace the class name with CprojectView as the class name; so if your dialog class was called CMyDlg it is renamed as CprojectView.

Note the name of the dialog of your CFormView class, such as IDR_PROJECTTYPE.  Write this down somewhere.

Delete the dialog from your SDI/MDI project.

Copy the dialog from your old project to your new project.

Rename it to the name that been used, such as IDR_PROJECTTYPE

Now proceed to the Common Conversion Section

Creating a CFormView-based additional view for a document

• In the CWinApp-derived class for your project, and add a declaration to the protected section of the header file:

  CMultiDocTemplate * YourClassNameHereTemplate;
  

• In the source file for the CWinApp-derived class, add the declaration, near where you declare your CMultiDocTemplate,

  YourClassNameHereTemplate = new CMultiDocTemplate(
          IDR_YOURCLASSNAMEHERE,
          RUNTIME_CLASS(YourExistingDocTemplateHere),
          RUNTIME_CLASS(CChildFrame),
          RUNTIME_CLASS(YourClassNameHere));

DO NOT call AddDocTemplate on this template!!!

• Add the header file to the header files included in the CWinApp-derived class

          #include "YourClassNameHere.h"

• Find the "parameter string" for your normal view in the STRINGTABLE, which will look like

  IDR_SOMETYPE  nnn   \nName\nName\n\n\nName.Document\nName Document

  Just duplicate it and rename it to

  IDR mmm\nName\nName\n\n\nName.Document\nName Document

  Note there is no change in content. The content doesn't really matter at this point, nor is it likely it ever will.

• Create a means, in the CWinApp-derived class, of creating the class. Where, formerly, you would do

          CYourClassNameHere dlg;
          dlg.DoModal();

  You now replace it with

          NewView(YourClassNameHereTemplate);

• Add the NewView method to your CWinApp-derived class:

  CDocument * CYourAppNameApp::NewView(CMultiDocTemplate * templ)
      {
       CDocument * doc = GetActiveDocument();
       if(doc == NULL)
          return NULL;
  
       CFrameWnd * frame = templ->CreateNewFrame(doc, NULL);
       if(frame == NULL)
          { /* failed to create */
           return NULL;
          } /* failed to create */
  
       templ->InitialUpdateFrame(frame, doc, TRUE);
       return doc;
      } // CFontExplorerApp::NewItem

Now proceed to the Common Conversion Section

Common Conversion (no matter which way you started)

• Convert the dialog template
  • Set the Border to "None"
  • Set the Style to "Child"
  • Set Visible to "Flase"
• Modify the header and source files for your dialog class
  • Add, at the front of the source file,

            IMPLEMENT_DYNCREATE(CYourClassName, CFormView)

  • In the header file, add, in the protected section

            DECLARE_DYNCREATE(CYourClassNameHere)

  • Change the constructor from

            CYourClassName::CYourClassName(CWnd * pParent)
                  : CDialog(CYourClassName::IDD, pParent)

    to

            CYourClassName::CYourClassName()
                  : CFormView(CYourClasName::IDD)

  • In the header file, change the constructor declaration accordingly.
  • Add the following methods to the .cpp file:

    #ifdef _DEBUG                        
    void CYourClassNameHere::AssertValid() const
    {                                                 
            CFormView::AssertValid();                 
    }                                                 
    
    void CYourClassNameHere::Dump(CDumpContext& dc) const
    {                                                  
            CFormView::Dump(dc);                       
    }                                                  
    #endif //_DEBUG                                    

  • Change the declaration

    BOOL CYourClassNameHere::OnInitDialog()
       {
        CDialog::OnInitDialog();
        ...
        return TRUE;  // return TRUE unless you set the focus to a control
                      // EXCEPTION: OCX Property Pages should return FALSE
       }

    to be

    void CYourClassNameHere::OnInitialUpdate()
       {
        CFormView::OnInitialUpdate();
        ...
        // Remove the return TRUE; and the comments
       } 

  • Change the declaration in the header file to match.
  • In the source file, replace all instances of "CDialog" with "CFormView" so the superclass calls all call the correct superclass

Compile and execute it.