Abstract: A control element for use in a graphical user interface, which combines the display features of the list box element and the pop-up menu element into a single GUI control element. The combined menu list control element is capable of displaying data in multiple states thereby allowing to it to optimally use the available display space for presenting data to the user. By allowing menu list control element to display data as either a list or a menu, it combines the advantages of lists and menus while avoiding their disadvantages.

Abstract: A system and method provide for synchronous operation of linked command objects in a general purpose software application. The software application provides a user with a variety of operations that manipulate available data objects. The software application manages the data objects in a number of contexts. Each context manages the existence and execution of a number of command objects. Each command object operates on one or more data objects in its context. To support synchronous operations that affect the state of data objects in more than one context, command objects are linked to each other. When one command object is executed, the context of the command object identifies a command object linked to the executed command object and initiates the execution of the linked command object via the context that manages that command object. This synchronization allows for synchronous undo and redone operations. The delete states of the command objects are also synchronized.

Abstract: In a computer display system, data structures or views are organized in a hierarchical manner. Each view has stored therein: (1) display information; (2) information pertaining to how that view is linked to other views in the hierarchy; (3) relative coordinates; (4) global coordinates indicating where on the display the view should be drawn; and (5) a valid flag indicating whether the global coordinates are currently valid. When a view is moved, its global coordinates are no longer valid. Thus, the valid flag in the view is reset to so indicate. In addition, the valid flag of all of that view's subviews are reset (if they are not already reset). The global coordinates of the view and subviews, however, are not immediately recomputed. Rather, the global coordinates of these views are recomputed only when they are needed, such as when they are accessed for display.