Legacy Interface Migration: A Task-Centered Approach

User Interface Specification After the analysis of a task, URGenT specifies an abstract GUI, which requires the user to input her data items (user variables and user input problem variables) only once, and buffers them appropriately to deliver them to all screens that use them. This GUI also retrieves from the legacy interface the asked data items” and feeds them to the appropriate screens. So in the above example, the user will enter her personal data and the customer name only. This interaction process is drastically simpler than the original one, where the user enters her personal data twice (to the two subsystems), writes down the claim number on paper and then enters this same number in three different screens to get different elements of the final report. At this point, for all data items to be manipulated, depending on their type, URGenT identifies a class of graphical interaction objects appropriate for the data−entry action at hand (Lewis & Rieman 1993). For example, for a tell action manipulating a date, appropriate graphical objects might be a calendar, a combination of three scrolling lists for year, month and day selection, a simple text entry box, etc. Graphical User Interface Generation The final step in the URGenT process is the actual generation of a GUI for implementing the user’s task. Having identified a class of graphical objects appropriate for each data item, URGenT proceeds to develop a dynamic HTML GUI with graphical objects appropriate for the users for which this GUI is intended. At this point, since we are dealing with report tasks, which are fairly small, this problem is simple in that only a single screen is needed with a few objects placed in a simple sequence according to the order of their use in the process. More complex tasks will require more elaborate approaches to the object layout problem. 4 Summary and Discussion In this paper, we discussed a process for the migration of a legacy system’s interface to a GUI. This process is based on the understanding of the user’s information−processing task, as extracted from traces of the user’s interaction with the system, and results in the design of task− and user− specific GUIs. We are currently working to extend this method from deterministic tasks, for which all traces of the same task consist of the same sequences of screens and actions, to more complex, non−deterministic tasks. Acknowledgements: This work has benefited from a lot of lively and in− depth discussions with the rest of the CelLest group, Paul Sorenson, Mohammad ElRamly and Roland Penner. It was supported by NSERC CRD 215451−98.