This method is used to get the number of child applications which belong to the current parent MDI container. This method accepts no parameters. It does not count all the child applications linked to the given MDI container, it counts only the currently running child applications. This method must be called from within the program serving as the MDI container. It returns an integer specifying the number of all child applications currently running. It returns 0, if no child applications are running:
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MENU
COMMAND "RUN_child"
RUN "child_app" WITHOUT WAITING
COMMAND "Exit"
IF ui.Interface.getChildCount()>0 THEN
ERROR "Yo have to close all child applications before exit"
ELSE
EXIT MENU
END IF
END MENU
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