The information in this article applies to:
- The Microsoft Foundation Classes (MFC), included with:
- Microsoft Visual C++ for Windows, versions 1.0, 1.5, 1.51 1.52
- Microsoft Visual C++ 32-bit Edition, versions 1.0, 2.0, 2.1, 4.0,
4.1, 4.2, 5.0
SUMMARY
It is sometimes desirable to create a CMultiDocTemplate based window (in
other words, a CFrame/CDocument/CView combination) without using the
mechanism provided by CWinApp::OnFileNew.
For example, if the program has multiple document templates,
CWinApp::OnFileNew will prompt the user with a dialog box asking which type
of document to open. The programmer may already know which type of
CMultiDocTemplate to use, and therefore may not want to prompt the user
because it would be inappropriate in the given context of the application.
MORE INFORMATION
Assuming the application was originally created with AppWizard, the
undocumented CMultiDocTemplate::OpenDocumentFile function can be used to
create a new CMultiDocTemplate based window. There are several steps
involved:
- Add a CMultiDocTemplate pointer to your CWinApp derived class:
class CMyApp : public CWinApp
{
...
public:
CMultiDocTemplate* m_pDocTemplate;
...
}
NOTE: If you plan to use multiple document types, you must create a
CMultiDocTemplate pointer member variable for each document type.
- In the call to CWinApp::InitInstance, remove the creation of the
CMultiDocTemplate from the call to AddDocTemplate. Set the pointer to
point to the new CMultiDocTemplate. Use the pointer to call
AddDocTemplate:
BOOL CMyApp::InitInstance()
{
...
m_pDocTemplate = new CMultiDocTemplate(IDR_TEXTTYPE,
RUNTIME_CLASS(CMyDoc),
RUNTIME_CLASS(CMDIChildWnd),
RUNTIME_CLASS(CMyView));
AddDocTemplate(m_pDocTemplate);
...
}
- Use the pointer to call CMultiDocTemplate::OpenDocumentFile with a NULL
parameter to create the new window. For this example, assume there is a
button in a CView window. In the BN_CLICKED handler for the button, we
want to create a window based on m_pDocTemplate:
void CMyView::OnNewWindowButtonClicked()
{
CMyApp* pApp = (CMyApp*)AfxGetApp();
pApp->m_pDocTemplate->OpenDocumentFile(NULL);
}
This same technique could be used to create a CSingleDocTemplate based
window in a Single Document Interface (SDI) application. However, it is
not necessary. Because there is only one document template for the
application, calling OnFileNew() will create the new window without
prompting the user for the type of document.
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