A Seamless Development Process of Adaptive User Interfaces Explicitly Based on Usability Properties

This work is aimed at the specification of usable adaptive user interfaces. A model-based method is used, which have been proved useful to address this task. The specification created is described in terms of abstract interaction objects, which are translated into concrete interaction objects for each particular platform. An adaptive engine is also proposed to improve the usability at runtime by means of a multi-agent system. A seamless process for adaptation development Currently different interaction paradigms are emerging due to several factors, such as ubiquitous access to information, the consideration of different user expertise levels, accessibility criteria or the wide range of interaction devices with specific capabilities (screen size, memory size, computing power, etc). In this paper a method is introduced for the specification of user interfaces of highly interactive systems with the capability of self-adapting to the changes in the context-of-use. To fill the gap between model-based user interface development approaches and adaptive user interface frameworks, we propose enriching the usual model-based user interface development, to include, in a seamless manner, the development of the adaptation facilities required for adaptive user interfaces development. We propose a method for the development of adaptive user interfaces called AL-BASIT (Adaptive Model-Based User Interface Method), which extends usual model-based user interface development methods to support the development of adaptive user interfaces in a seamless way. Our proposal starts with requirements analysis to identify the tasks that will drive the design. Also user, physical environment and platform characteristics are collected to complete requirements analysis. In requirements analysis, use cases are used to identify the tasks and to establish a comprehensible channel of communication with the user, using an artefact understandable by the user and the designer. This stage is completed gathering the required data from the potential context-of-use for the application (user, platform and environment models). Analysis stage in aimed at the transformation of the requirements into a specification 310 Víctor López-Jaquero et. al. easier to handle, and usually in a more compact format. It also brings requirements analysis data closer to designer language. In our approach, we are using UML class diagrams to describe the domain model. To support human role multiplicity, we match each possible role a user can assume when using the user interface with the tasks they can perform. After analysis stage, design phase take place using the proposed tool. The design is based on the description of the identified tasks and their relationships with the domain elements they make use of. The task model is enriched describing the events to change from one task/action to another with the canonical abstract user interface tools [1]. From this data, an abstract user interface is generated which is independent of both modality and platform. Then, a translation is made to a concrete user interface (CUI) expressed in USIXML (http://www.usixml.org) user interface description language. The coordination between the CUI elements, the application functional core and the final running code is performed by means of connectors, as described in [2][3] This specification is adapted at runtime using a transformational approach. The adaptation engine reasons about the possible adaptation and preserves different usability properties according to the usability tradeoff specified in terms of I* specification technique [4].