Abstract. To cope with the ever increasing diversity of markup languages, programming languages, tool kits and interface development environments, conceptual modeling of user interfaces could bring a framework for specifying, designing, and developing user interfaces at a level of abstraction that is higher than the level where code is merely manipulated. For this purpose, a complete environment is presented based on conceptual modeling of user interfaces of information systems structured around three axes: the models that characterize a user interface from the end user’s viewpoint and the specification language that allows designers to specify such interfaces, the method for developing interfaces in forward, reverse, and lateral engineering based on these models, and a suite of tools that support designers in applying the method based on the models. This environment is compatible with the Model-Driven Architecture recommendations in the sense that all models adhere to the principle of separation of concerns and are based on model transformation between the MDA levels. The models and the transformations of these models are all expressed in UsiXML (User Interface eXtensible Markup Language) and maintained in a model repository that can be accessed by the suite of tools. Thanks to this environment, it is possible to quickly develop and deploy a wide array of user interfaces for different computing platforms, for different interaction modalities, for different markup and programming languages, and for various contexts of use. 1

The mapping problem has been defined as any method aimed at mapping models capturing various aspects of an interactive system throughout their development life cycle to support model-based design of user interfaces. This field has followed a long tradition of establishing models and maintaining mappings between them so as to create and maintain accurate specifications of a user interface. In this paper, potential mappings between models are defined so as to create a uniform and integrated framework of adding, removing, and modifying mappings throughout the development life cycle of interactive systems. The mappings can be established from any source model to any target model, one or many, in the same formalism, or from any model element to any other. Those models include task, domain, presentation, dialog, and context of use. The context of use is itself decomposed into user, platform, and environment. To support the manipulation of mappings between models, two examples of supporting software are detailed. TRANSFORMIXML consists of a Java application that triggers transformations of models expressed by graph grammars. IDEALXML consists of a Java application allowing the designer to edit any model at any time, and element of any model and to establish a set of mappings. Both software are based on UsiXML, a

Multi-fidelity prototyping combines within a single user interface prototype several elements whose representations are reproduced with different levels of fidelity with respect to the final user interface: no fidelity at all, low fidelity, medium fidelity, and high fidelity. In order to effectively and efficiently support multi-fidelity, an original set of techniques is defined and discussed: multiple representation manipulation by sketching and gesture recognition, smooth transition between any representation at any time, prototype reusability, multi-platform support, and multiple user interface prototyping facilities. The full implementation of these techniques in prototyping software provides designers and developers with a unique environment for exploring multiple designs with unprecedented support for quickly designing interfaces from scratch or from previously existing design templates. An experimental study reveals that the multiple representation manipulation together with smooth transition represents a valuable advantage for naturally designing user interfaces. The prototyping software supports several aspects involved in the user interface development life cycle and is convenient for non-WIMP user interfaces.

Abstract. Sketching activities are widely adopted during early design phases of user interface development to convey informal specifications of the interface presentation and dialog. Designers or even end users can sketch some or all of the future interface they want. With the ever increasing availability of different computing platforms, a need arises to continuously support sketching across these platforms with their various programming languages, interface development environments and operating systems. To address needs along these dimensions, which pose new challenges to user interface sketching tools, SketchiXML is a multi-platform multi-agent interactive application that enable designers and end users to sketch user interfaces with different levels of details and support for different contexts of use. The results of the sketching are then analyzed to produce interface specifications independently of any context, including user and platform. These specifications are exploited to progressively produce one or several interfaces, for one or many users, platforms, and environments. 1

The mapping problem has been defined as the way to map models involved throughout the development life cycle of user interfaces. Model-based design of user interfaces has followed a long tradition of establishing models and maintaining mappings between them. This paper introduces a formal definition of potential mappings between models with its corresponding syntax so as to create a uniform and integrated framework for adding, removing, and modifying mappings throughout the development life cycle. For the first time, the mappings can be established from any source model to any target model, one or many, in the same formalism. Those models include task, domain, presentation, dialog, and context of use, which is itself decomposed into user, platform, and environment. IDEALXML consists of a Java application allowing the designer to edit any model at any time, and any element of any model, but also to establish a set of mappings, either manually or automatically based on a mapping model.

This paper aims to provide a discussion of how model-based approaches and related tools have been used to address important issues for obtaining usable interactive software and the new challenges for this research area. The paper provides an analysis of the logical descriptions that can be used in the design of interactive systems and how they can be manipulated in order to obtain useful results. This type of approach has recently raised further interest in the ubiquitous computing field for supporting the design of multi-device interfaces. The new challenges currently considered are mainly in the area of end-user development, ambient intelligence, and multimodal interfaces.

During these last years, many researchers have proposed new alternatives for early interface design based on handsketch. But these new alternatives seem to be dedicated to obsolescence as they only offer the possibility to generate user interfaces for a single platform in a unique language. Indeed, in a context where the number of computingplatforms and system environments is exploding, new alternatives should be considered. This paper presents an innovating alternative with SketchiXML, a multi-agent application able to handle several kinds of hand-drawn sources as input, and to provide the corresponding specification in USIXML (USer Interface eXtensible Markup Language), a platform-independent user interface description language.

Developing advanced User Interfaces (UI) is very challenging, in particular when many variants of a same UI are to be produced for different platforms. The development of plastic user interfaces is even more demanding. In Human Computer Interaction, plasticity denotes the capacity of a UI to withstand variations of the context of use while preserving usability. A context of use is a triplet < user, platform, environment>. Plasticity raises many issues for both the design and run time of UIs. This paper shows how Model Driven Engineering concepts can be used in this area. 1.

Today a large variety of mobile interaction devices such as PDAs and mobile phones enforce the development of a wide range of user interfaces for each platform. The complexity even grows, when multiple interaction devices are used to perform the same task and when different modalities have to be supported. We introduce a new dialog model for the abstraction of concrete user interfaces with a separate advanced control layer for the integration of different modalities. In this context, we present the Dialog and Interface Specification Language (DISL), which comes with a proofof-concept implementation.

In ubiquitous computing, interactive applications are shipped with different variations of its user interface depending on the constraints imposed by the context in which they are running, such as the user, the computing platform and environment. A multi-presentation user interface is composed of a series of interconnected user interfaces for the same task to be carried out in different contexts of use. When access to software applications must be guaranteed in more than one context of use, it is necessary to automatically adapt the interface in order to preserve their usability when context switching occurs, for instance, a switch from a desktop to a pocket computer. To achieve this goal, this paper proposes a model and a visualization technique to express and manipulate the plasticity domains of a multipresentation user interface. The plasticity domain denotes the set