CFrameWnd::LoadFrame

The following is a summary of what CFrameWnd::LoadFrame does.

• First it sets CFrameWnd::m_nIDHelp to the nIDResource parameter for use by context-help.
• Then it gets the resource string with resource id nIDResource.
• Then it calls the AfxDeferRegisterClass macro to register the window class if it is not already registered.
• Then LoadFrame calls CFrameWnd::Create(Parameters) which does:
  • loads the menu with resource id of the LoadFrame nIDResource parameter
  • Sets CFrameWnd::m_strTitle to the lpszWindowName parameter
  • Then Create calls CFrameWnd::CreateEx (Parameters) which does:
    • PreCreateWindow
    • AfxHookWindowCreate(this)
    • ::CreateWindowEx(Parameters)
    • AfxUnhookWindowCreate()
• Sets m_hMenuDefault to the menu for the window
• Loads the accelerator table with resource id nIDResource
• if a context was not supplied, it sends a WM_INITIALUPDATE message to all descendant windows

MFC WindowCreate Hook

That does not appear to be much that LoadFrame does; it might appear that a view is never created by LoadFrame. However AfxHookWindowCreate sets a hook that does do more. I do not know the details of how it works but based on the call stack when the view is constructed, the hook results in CFrameWnd::OnCreate being called. I assume this is the mechanism always used to execute OnCreate when a window is created. CFrameWnd::OnCreate calls OnCreateHelper using the LPCREATESTRUCT parameter and the pContext from the LPCREATESTRUCT parameter.

CFrameWnd::OnCreateHelper does the following:

• Calls CWnd::OnCreate
• Calls OnCreateClient, which, if a context with a new view class is supplied, calls CreateView (and that is where the view is created) with the context and an id of AFX_IDW_PANE_FIRST
• Sends (using PostMessage) a WM_SETMESSAGESTRING message to set the status bar message to the string with a resource id of AFX_IDS_IDLEMESSAGE
• Calls RecalcLayout

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