Multipath Transformational Development of User Interfaces with Graph Transformations

In software engineering, transformational development is aimed at developing computer systems by transforming a coarse-grained specification of a system to its final code through a series of transformation steps. Transformational development is known to bring benefits such as: correctness by construction, explicit mappings between development steps, and reversibility of transformations. No comparable piece exists in the literature that provides a formal system applying transformational development in the area of user interface engineering. This chapter defines such a system. For this purpose, a mathematical system for expressing specifications and transformation rules is introduced. This system is based on graph transformations. The problem of managing the transformation rules is detailed, e.g., how to enable a developer to access, define, extend, restrict or relax, test, verify, and apply appropriate transformations. A tool supporting this development paradigm is also described and exemplified. Transformational development, applied to the development of user interfaces of inter-