Technique G10:Creating components using a technology that supports the accessibility API features of the platforms on which the user agents will be run to expose the names and roles, allow user-settable properties to be directly set, and provide notification of changes

Applicability

Programming technologies that have standard components programmed to interface with accessibility APIs.

This technique relates to 4.1.2: Name, Role, Value (Sufficient using a more specific technique).

Description

The objective of this technique is to allow assistive technology to understand Web content so that it can convey equivalent information to the user through an alternate user interface.

Sometimes content is not created using markup language but rather using a programming language or tools. In many cases, these technologies have interface components that are already programmed to interface with accessibility APIs. If an author uses these components and fills in the properties (e.g., name, etc.), the resulting user interface components in the content will be accessible to assistive technology.

However, if an author wants to create a user interface component that is new and they cannot use standard components, then they need to be sure to add the accessibility provisions themselves - and implement them in a way that is compatible with the accessibility API.

After completion, the custom component should be tested for Accessibility Support.

Examples

  • A Web page uses java to create an applet. A group of authors wants to create an entirely new type of interface component so they cannot use existing Java objects. They use Java swing classes to create their component because the Java swing classes already have provisions for connecting to different accessibility APIs. Using the Java swing classes they are able to create an interface component that exposes its name and role, is able to be set by AT and alerts AT to any updates.
  • A Web page uses an original ActiveX control that is written in the C++ programming language. The control is written to explicitly support the Microsoft Active Accessibility (MSAA) API to expose information about accept commands. The control then interacts directly with assistive technology running the user agent on systems that support MSAA.

Tests

Procedure

  1. Render content using an accessible User Agent.
  2. Use an Accessibility Tool designed for the Accessibility API of the User agent to evaluate each user interface component.
  3. Check that name and role for each user interface component is found by the tool.
  4. Change the values on the component.
  5. Check that the Accessibility tool is alerted.
  6. Check that the component works with assistive technologies.

Expected Results

  • Checks #3, #5 and #6 are true for each user interface component.