The Main Frame Window and Document Classes
Up to now, we've been using a view window as if it were the application's only window. In a Single Document Interface (SDI) application, the view window sits inside another window—the application's main frame window. The main frame window has the title bar and the menu bar. Various child windows, including the toolbar window, the view window, and the status bar window, occupy the main frame window's client area, as shown in Figure 12-1. The application framework controls the interaction between the frame and the view by routing messages from the frame to the view.

Figure 12-1: The child windows within an SDI main frame window.
Look again at any project files generated by the MFC Application Wizard. The
