You create accessible content by using accessibility features included with Flex, by taking advantage of ActionScript designed to implement accessibility, and by following recommended design and development practices.

Visually impaired users, for example, might rely on assistive technology such as screen readers, which provide an audio version of screen content, or screen magnifiers, which display a small portion of the screen at a larger size, effectively reducing the visible screen area. Hearing-impaired users might read text and captions in the document in place of audio content. Other considerations arise for users with mobility or cognitive impairments.

The following list of recommended practices is not exhaustive, but suggests common issues to consider. Depending on your audience's needs, additional requirements may arise.

Visually impaired users 

For visually impaired users, keep in mind the following design recommendations:

• Design and implement a logical tab order for the tabs.
• Design the document so that constant changes in content do not unnecessarily cause screen readers to refresh. For example, you should group or hide looping elements.
• Provide captions for narrative audio. Be aware of audio in your document that might interfere with a user being able to listen to the screen reader.
• Use percentage sizing so that your applications scale properly at smaller screen sizes. This allows users of screen magnifiers to see more of your application at one time. Also take into account that many visually impaired users run applications with lower screen resolutions than other users.
• Ensure that foreground and background colors contrast sufficiently to make text readable for people with low vision.
• Ensure that controls don't depend on the use of a specific pointer device, such as a mouse or trackball.
• Ensure that components are accessible by keyboard. All Flex components defined as accessible include keyboard navigation. For a list of these components and the available keyboard commands for each, see Accessible components and containers.

Color-blind users 

For color-blind users, ensure that color is not the only means of conveying information.

Users with mobility impairment 

For users with mobility impairment, keep in mind the following design recommendations:

• Ensure that controls don't depend on the use of a specific pointer device.
• Ensure that components are accessible by keyboard. All Flex components defined as accessible include keyboard navigation. For a list of these components and the available keyboard commands for each, see Accessible components and containers.

Hearing-impaired users 

For hearing-impaired users, ensure that you add captions to audio content.

Users with cognitive impairment 

For users with cognitive impairments, such as dyslexia, keep in mind the following design recommendations:

• Ensure an uncluttered, easy-to-navigate design.
• Provide graphical imagery that helps convey the purpose and message of the application. These graphics should enhance, not replace, textual or audio content.
• Provide more than one method to accomplish common tasks.

About worldwide accessibility standards

Many countries, including the United States, Australia, Canada, Japan, and countries in the European Union, have adopted accessibility standards based on those developed by the World Wide Web Consortium (W3C). W3C publishes Web Content Accessibility Guidelines, a document that prioritizes actions that designers should take to make web content accessible. For information about the Web Accessibility Initiative, see the W3C website at www.w3.org/WAI.

In the United States, the law that governs accessibility is commonly known as Section 508, which is an amendment to the U.S. Rehabilitation Act. Section 508 prohibits federal agencies from buying, developing, maintaining, or using electronic technology that is not accessible to those with disabilities. In addition to mandating standards, Section 508 lets government employees and the public sue agencies in federal court for noncompliance.

For additional information about Section 508, see the U.S. government-sponsored website at www.section508.gov.

Viewing the Flex Accessibility web page

This topic contains an introduction to the accessibility features in Flex and to developing accessible applications. For the latest information on creating and viewing accessible Flex content, including supported platforms, known issues, screen reader compatibility, articles, and accessible examples, see the Flex Accessibility web page at www.adobe.com/go/flex_accessibility.