On the Software Structure of User Interface Management Systems

Abstract

Specific systems for the development of user interfaces (Uls) are used today for coping with the increasing problems of human-computer communication. Some of those systems are based on well-defined models for humancomputer interaction. Important requirements of such systems are: consideration of standards, most notably graphics functionality and windowing functionality, openness to all interaction styles, and provision of comfortable design tools that allow UI prototyping. An evaluation of the existing systems reveals that they fulfill only some of those requirements. We present a layered model for the interface between an application's functionality and its UI, which explicitly takes care of standards. Based on this model we implement a system for efficient design and administration of Uls. An internal interface among all tools, namely, a PROLOG-like formalism used for the description of UI objects, is of central importance. This formalism makes all tools independent from the dialog objects, hence our system is truly open. The core of our system consists of a comfortable graphically interactive editor for UI design and an interpreter. The interpreter is mainly responsible for the presentation of Uls which are described according to this formalism. The output of the editor will be a description of Uls according to the formalism. Our oal is the development of a functionally complete object-oriented set of formalism-based tools; these tools will also use artificial intelligence techniques for an adaptation of Uls to user needs.