Formal Models for Informal GUI Designs

Many different methods exist for the design and implementation of software systems. These methods may be fully formal, such as the use of formal specification languages and refinement processes, or they may be totally informal, such as jotting design ideas down on paper prior to coding, or they may be somewhere in between these two extremes. Formal methods are naturally suited to underlying system behaviour while user-centred approaches to user interface design fit comfortably with more informal approaches. The challenge is to find ways of integrating user-centred design methods with formal methods so that the benefits of both are fully realised. This paper presents a way of capturing the intentions behind informal design artefacts within a formal environment and then shows several applications of this approach.