A method and apparatus for a menu based system containing size and location information is disclosed. Each menu contains a list of menu items containing a command and variables that reflect the command's current appearance. This includes status information determinative of the menu item's state (enabled/disabled), its name, its associated graphic, and whether its appearance is currently valid. Each of these were initialized when the menu item was created. The invention creates a menu item from a command, where a menu item is another object data structure containing a command sequence. The menu item is added to a list of menu items, and initialized as an invalid appearance. Later when the menu item is selected from a pull down menu, the appearance state is recomputed based on the system state.

A system of the present invention includes a PC-based relational database management system (PC RDBMS) with data integrity facilities. Methods are described for maintaining referential integrity between data tables which may be freely moved to various remote workstations--ones which do not have ready access to a centrally-maintained data dictionary. The system provides each table with descriptors for tracking referential integrity links or relationships among various tables, regardless of a particular situs where a table resides. A preferred interface is also described for permitting end-users to easily define referential integrity links between data tables.

orkspaces provided by an object-based user interface appear to share windows and other display objects. Each workspace's data structure includes, for each window in that workspace, a linking data structure called a placement which links to the display system object which provides that window, which may be a display system object in a preexisting window system. The placement also contains display characteristics of the window when displayed in that workspace, such as position and size. Therefore, a display system object can be linked to several workspaces by a placement in each of the workspaces' data structures, and the window it provides to each of those workspaces can have unique display characteristics. The display system object can operate continuously despite switching between one workspace and another, and the windows it provides in successive workspaces can share features so that they appear to the user to be the same window or versions of the same window. As a result, the workspaces appear to be sharing a window. Workspaces can also appear to share a window if each workspace's data structure includes data linking to another workspace with a placement to the shared window.

Workspaces provided by an object-based user interface appear to share windows and other display objects. Each workspace's data structure includes, for each window in that workspace, a linking data structure called a placement which links to the display system object which provides that window, which may be a display system object in a preexisting window system. The placement also contains display characteristics of the window when displayed in that workspace, such as position and size. Therefore, a display system object can be linked to several workspaces by a placement in each of the workspaces' data structures, and the window it provides to each of those workspaces can have unique display characteristics. The display system object can operate continuously despite switching between one workspace and another, and the windows it provides in successive workspaces can share features so that they appear to the user to be the same window or versions of the same window. As a result, the workspaces appear to be sharing a window.

Activation of the action handle signals the CPU of selections associated with the data object. Tapping or clicking on the action handle causes display of a context menu containing at least one command that may be invoked with respect to the data object. Dragging the action handle indicates movement or dragging of the action handle and the corresponding data object for an operation associated with dragging such as drag-and-drop. The use of action handles in association with data objects eliminates ambiguity between actions intended to create digital ink with respect to a pen-based computer system and actions intended to invoke a command or other interaction with the computer system.

A system for a multimedia slide presentation having a computer, display screen, sound system, video disc, video cassette recorder, photo compact disc drive, compact disc read only memory (CD ROM), and a pointing device (trackball or mouse). Each slide may contain photographs, text, graphics, and charts, or any combination of various media. By actuating and releasing the second control button of the mouse or trackball, a tracked, popup menu is displayed in the multimedia slide system and aids the user to make selections that operate on the slides and objects on the slides. The popup menu contains a button bar, a title bar, and a list of textual menu items. Buttons in the button bar provide an appealing "shortcut" to frequently used commands. The text menu items may also indicate another cascaded, popup menu when selected.

A method and apparatus is described for using directional gestures in popup menus to enter data and control a computer system. A popup menu contains a number of items (50-61, 70, 72, 74, 134, 136-141, 151-156) represented by images (165) or labels (167) positioned on a regular grid around a popup position. When an operator requests a popup menu using a trigger event, the appropriate menu for the operator, trigger, and the system state is selected and is displayed with the popup position (54, 132, 133, 135, 150, 158) centered over the current cursor position. The operator scans through the items by dragging the cursor (46) and selects one to initiate the associated action. The operator can design menus containing the commands he or she uses most frequently and use these menus with existing applications without revising the applications.

Method and apparatus for creating a movable enhanced tracked popup menu (200) in response to actuation of a secondary button (102) on a pointing device (10) in a computer system (100) having a graphics user interface. The popup menu (200, 300) comprises a title bar (201), a button bar (202), and a menu list.

The CPU is further coupled to a cursor control device which permits a user to selectively position a cursor at adesired location on the display, and signal the CPU of selections in accordance with the teachings of the present invention. Images are generated in the form of "windows" by the CPU which include standard window features as well as text, icons, and buttons which correspond to functions to be executed by the CPU.

A method or process is disclosed for displaying help information to users of computer programs. The process is application independent and provides context sensitive help information for a particular subject selected by the user. The help information is customized to the needs of an individual user. The process also automatically provides help information for the particular subject matter selected by the user from other contexts without having the user select the other contexts or even know about the existence of the other contexts. The help information is displayed to the user without interrupting the application currently being run by the user.

This paper describes the design and implementation of a Computer Process Control System for a High Temperature Workstation performing Selective Laser Sintering of metal and .ceramic powders. The increased complexity and sophistication of the new workstation requires a variety of measurement and control devices which are interfaced to a process control computer. This process control system incorporates a XView (a X Window System Toolkit) based Graphical User Interface which allows the user to set and change process parameters on-line as well as receive graphical feedback on the process.

A workspace data structure, such as a window hierarchy or network, includes functional data units that include data relating to workspace functionality. These functional data units are associated with data units corresponding to the workspaces such that a functional data unit can be replaced by a functional data unit compatible with a different set of functions without modifying the structure of other data units. Each workspace data unit may have a replaceably associated functional data unit called an input contract relating to its input functions and another called an output contract relating to its output functions.