AddSubMenuAddSubMenu — creates a submenu on a parent menu.
AddSubMenu (parent, pos, label)
parentThe parent menu for this submenu, such as that returned by a call
to CreateSystemMenu or AddSubMenu.
posAn integer designating the position of this item on the menu.
labelThe name of the submenu, as a text string, that will actually appear.
The value of the ._CustomSubmenu class variable, a positive
integer.
This method adds a submenu to the DataHub system tray menu. The submenu can then be used for adding menu items or other submenus.