Testing GUI accessibility using the Eclipse Raven method

Validate Java-based GUI accessibility with IBM rule-based Accessibility validation Environment

Introduction: ibm®rule-based Accessibility Validation Environment (RAVEN) is an Eclipse plug-in that provides run-time checking of GUI components to ensure continuous use of Java™ accessibility features 。 This article examines the RAVEN tool and illustrates how it can be used to validate Java Swing applications.

Creating a graphical user interface for software systems presents a dual challenge to adaptive technologies in terms of usability and design. These types of interfaces will create difficulties for individuals with visual, auditory or physical disabilities. Although the Eclipse platform supports a rich client interface based on Java, Swing, or Standard Widget Toolkit (SWT), it does not validate these interfaces directly, making it impossible to ensure that adaptive technologies, such as screen readers, can access all visual elements.

One of the greatest achievements in computer science is the invention of the GUI. By combining common icons and visible command representations, such as using a mouse click button, the computer is becoming familiar to people and becoming as commonplace as a phone. However, for people with disabilities, especially those with visual impairment, this advantage poses great difficulties. A large proportion of people will not be able to enjoy the right to use the computer without making adjustments to enable such people to use the computer's functions.

There are some other regulatory reasons for creating an accessible interface. In 1998, the United States Congress passed an amendment to the rehabilitation Act, which ordered all federal agencies to enable disabled people to use computer technology. The code applies to all software used by the federal government, including software developed by itself, Software purchased, or software obtained by other means. Therefore, if your company is one of many software development companies bidding on federal government projects, you must ensure that the delivered applications meet regulatory requirements.

There are three major categories of disabled people who need to use adaptive technology:

Blind or visually impaired users-the following support is required: A textual description of all graphical control elements, a sound hint for the action result, a prompt for focus transfer (representing the selected graphical element), and a way to prompt for the default action.

Hearing impaired users-for such individuals, you must provide a visual cue for sound prompts, or provide a textual description of what you hear.

Users with mobility impairments-for such individuals, other input devices, such as eye-tracking technology (eye-tracking) and oral input, must be provided.

Fortunately, the computer interface that caused this kind of distress can be designed to facilitate interaction with assistive devices. For example, the Java programming language supports many features that enable visually impaired users to use devices, such as screen readers, refreshing Braille representations, and high-contrast graphics. To take advantage of these features, steps must be taken to ensure that all elements of the interface are accessible, which is challenging for most developers who do not understand these features. It takes a lot of effort to check whether each GUI element meets the requirements individually, and few software development companies have tested the assistive devices.