Class TMDIFrame     Inherits from Class TWindow
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 DATA
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 oWndClient           The TMDIFrame's client window, an instance of TMDIClient.
 oWndActive           The TMDIFrame's active MDI child window.
 nMenuPos             Contains the position in the TMDIFrame window menu
                      of the child window submenu.

 METHODS
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 New                  Generic constructor method
 Tile                 Tile Child windows
 Cascade              Cascade child windows
 ArrangeIcons         Arrange all minimized document child windows. It does
                      not affect child windows that are not minimized.
 NextWindow           Activate the child window immediately behind the
                      currently active child window and place the currently
                      active child window behind all other child windows.
 ChildNew             Creates an New TMDIChild.
 Release              Destroy a TMDIFrame window and all his child objects