Visual C++ and MFC Programming 2nd Edition

Visual C++ and MFC Fundamentals Chapter 5: The Document/View Architecture

return TRUE;

}

The above code allows only creating a window frame for the parent window. To allow

the user to interact with the computer through your MDI, you must provide a template for

a document. The child document must have its own frame, distinct from that of the

parent. To provide this frame, you have two main alternatives. You can directly use the

CMDIChildWnd class or you can derive your own class from CMDIChildWnd:

class CChildFrame : public CMDIChildWnd

{

DECLARE_DYNCREATE(CChildFrame)

DECLARE_MESSAGE_MAP()

};

As opposed to a Single Document Interface application, to create a Multiple Document

Interface (MDI) application, you use the CMultiDocTemplate class which, like the

CSingleDocTemplate class, is derived from CDocTemplate. Therefore, you must declare

a pointer variable to CMultiDocTemplate using the new operator, then use its constructor

to initialize the template. The syntax of the CMultiDocTemplate constructor is:

CMultiDocTemplate(UINT nIDResource,

CRuntimeClass* pDocClass,

CRuntimeClass* pFrameClass,

CRuntimeClass* pViewClass);

To make a document different from the parent, you must create an additional series of

resources that share a common name other than IDR_MAINFRAME. The most basic

resources you should create are a menu and an icon. There are two main types of MDI

applications.

One kind of application may use only one particular category of documents such as only

text-based. Because text-based documents can include ASCII text files, rich text

documents (RTF), HTML files, script-based documents (JavaScript, VCScript, Perl,

PHP, etc), etc, such an application may be configured to open only that type of document.

To create such an MDI application, in the constructor of the CMultiDocTemplate object

that you are using, specify a CView derived class (CEditView, CListView, etc) or your

own class you derived from CView or one of its children. Here is an example:

BOOL CMultiEdit1App::InitInstance()

{

CMultiDocTemplate* pDocEdit;

pDocEdit = new CMultiDocTemplate(

IDR_EDITTYPE,

RUNTIME_CLASS(CMultiEdit1Doc),

RUNTIME_CLASS(CChildFrame),

RUNTIME_CLASS(CEditView));

AddDocTemplate(pDocEdit);

// create main MDI Frame window

CMainFrame* pMainFrame = new CMainFrame;

if (!pMainFrame->LoadFrame(IDR_MAINFRAME))

return FALSE;

m_pMainWnd = pMainFrame;

CCommandLineInfo cmdInfo;