In this paper we argue that while there exist several
approaches to modeling user interfaces of web ap-
plications when adopting a Model Driven Devel-
opment methodology, too little attention is payed
to the actual abstract behavior of the interface. In
the UML-IDEA approach we adopt the UML as
a modeling language and start from a very abstract
view of the UI specified in terms of state machines.
We claim that expressivity of the language is suf-
ficient to capture, even at the abstract level, many
usability problems. At the same time, transforma-
tions of models into more concrete levels generate
executable code and test cases, wireframe proto-
types and representations suitable also for accessi-
bility assessments. In this way usability and acces-
sibility investigations could be carried out during
conceptual design.
