On the design of a graphical transition network editor

Abstract

This paper describes a graphical editor for the SYNICS user-interface development system. SYNICS is based on transition network diagrams and uses a grammar to specify the pattern matching of user input. Complex SYNICS programs can be difficult for the designer to comprehend making development slow and prone to errors. The editor described here is intended to increase the designers comprehension by allowing him to define the user interface on a computer in terms of diagrams. Transition network diagrams are used to describe the control structure of the interface and railroad diagrams are used to describe associated syntax rules. These diagrams may be drawn and manipulated by the designer and the information extracted from them is used to check the design for errors and automatically generate their corresponding SYNICS description. The design considerations for this system are discussed.