Command routing beyond a split frame

Abstract: The article present a simple method
of routing WM_COMMAND messages through a number of views in a split
frame window. This simplifies dealing with command routing and UI updates for
inactive views.

The standard framework route does not include inactive
views, which causes toolbar buttons and menus to gray when their mother view is
deactivated. Users are confused. To bring back their happiness, I have
overridden the CCmdTarget::OnCmdMsg function in the main frame (obviously
derived from CFrameWnd):


BOOL CMainFrame::OnCmdMsg(UINT nID, int nCode, void* pExtra, AFX_CMDHANDLERINFO* pHandlerInfo)
{
    CDocument *pDoc = GetActiveDocument();
    if(pDoc)
    {
	POSITION pos = pDoc->GetFirstViewPosition();
	CView *pView = NULL;
	while(pView = pDoc->GetNextView(pos))
	{
	    if(pView != GetActiveView()
		&& pView->OnCmdMsg(nID, nCode, pExtra, pHandlerInfo))
		return TRUE;
	}
    }

    return CFrameWnd::OnCmdMsg(nID, nCode, pExtra, pHandlerInfo);
}

I used a list of views contained in the active document (if any).
The command message is passed to all views but the active one,
which had a chance to handle it before it was routed to the frame
window. If the message is handled by one of the views (OnCmdMsg indicates it by
returning TRUE), no further processing is needed and we can return. Otherwise,
the base class member is called to restore the conventional framework route.

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