Barrierefreiheit im virtuellen Raum - benutzungszentrierte und modellgetriebene Entwicklung von Weboberflächen

  • Accessibility in cyberspace - usage-centered and model-driven development of web user interfaces

Vieritz, Helmut; Fromhold-Eisebith, Martina (Thesis advisor); Jeschke, Sabina (Thesis advisor)

Aachen : Publikationsserver der RWTH Aachen University (2015)
Dissertation / PhD Thesis

Aachen, Techn. Hochsch., Diss., 2015


Since the 1990s, accessibility of Web applications plays an important role in the development of technology. Meanwhile, a web application requires a complex software development process with analysis, specification and design activities. Successful implementation of accessible user interfaces is based on their integration into early analysis and design activities. Since current accessibility guidelines address only runtime behavior, additional efforts are required to transform and integrate the requirements into analysis and design of Web applications. This research work investigates the requirements of accessibility for the user as well as the requirements of Web application design. A software process model for Web applications is defined that helps software architects and developers to meet the requirements of accessibility during analysis and design activities. The approach combines usage-centered design with model-driven development to bridge the gap between user and developer. The investigation starts with the analysis of accessible human-computer interaction and the state of the art in development of accessible Web applications. User’s tasks and workflow are taken as a starting point for user interface (UI) design based on the universal design paradigm. Current guidelines for accessible user interface behavior are refined for modeling. The relationship between software architecture and accessibility is examined to include complementary aspects of the software development process. The resulting software development process integrates the requirements of accessible interaction in early development activities. After investigating the Human-computer interaction (HCI) and software architecture for accessibility, a model-driven design approach for Web-based UI design is presented which overlaps the essential models in HCI including the task, dialog and presentation model. The Unified Modeling Language (UML) is used as a meta model and for notation. An additional chapter examines alternative access to UML diagrams. Pre-implementation accessibility evaluation is investigated based on rapid prototyping and model-driven tests. As a case study, the concept is used and tested for an accessible Web interface in data and information integration. The combination of usage-centered and model-driven design supports user’s needs for accessible interaction as well as the integration into modern Web application development. To follow commons conditions of recent Web development, standard UI software architecture and a reference framework for model-driven UI design are used. Finally, the research work is completed with the transfer of the process model to other domains of application with focus on multiplatform-development.