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Why it Matters |   How To... |   Testing |   Guidelines

Why it Matters

With the increase in interactive pages and alternative presentation methods, new accessibility challenges are created.

Screen reader users may be unable to get any information from a Flash website. Mobile phone users may not be able to access JavaScript based menus. Users who turn off Active X for security reasons may be unable to read parts of your website. Those with JavaScript disabled will not be able to access information presented using Ajax.

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How To...

Create Accessible Flash

Later versions of Macromedia Flash make it easy to add accessibility features to Flash videos. It is time consuming to create fully accessible flash, however these are some of the key elements to accessible Flash:

  • Provide text equivalents to graphics, animations, buttons, and videos
  • Embed audio into Flash rather than playing a separate file
  • Provide a logical tab order for Flash interface elements such as forms and content
  • Allow the user as much control as possible, such as being able to turn off background sounds,
Further information can be found in a detailed and well written tutorial on 'Creating Accessible Macromedia Flash Content' . Macromedia themselves also produce some useful guidance assistance and if you already have a basic understanding of accessible Flash there is a discussion of several more advanced topics at A List Apart.

Some examples of accessible Flash include:

Create Accessible Java

There are several accessibility features built into existing Java classes, in particular the Swing components.

The four main components that Sun provide to make accessible Java:

  • The Java Accessibility API - this defines what information is available in an application or applet that can be used by assistive technologies
  • The Java Accessibility Utilities - this allows assistive technology to get to the information offered up via the accessibility API
  • The Java Access Bridge allows assistive technology to access the JVM
  • The Java Foundation Classes - graphical user-interface components (including Swing) which fully implement the Java Accessibility API
Sun provide tutorials on accessible java as well as further details about implementation. IBM produce a set of guidelines on how to create accessible Java, supported by examples.

Some examples of these guidelines are:

  • Use dynamic GUI layout. Do not call setSize() with constant values
  • Provide access keys to provide easy access to each menu
  • Add components to Containers in the logical order that they should be read on screen
  • Avoid using keyboard shortcuts that are used elsewhere e.g. Ctrl+C, for cut
  • Extend a Swing class as far down the inheritance hierarchy as possible when creating custom components
  • Provide documentation on all accessibility features including keyboard access, as part of the regular product documentation.
  • Provide support for system settings

Many of the WCAG guidelines [link] are also still useful.

There are specific guidelines for the creation of applets.

Screen reader users will need to download and configure the Java Access Bridge in order to access Java.

Create Accessible JavaScript

The current WAI guidelines state that your pages should be usable even when JavaScript is turned off. Screen readers have been developed a lot since the guidelines were written however, and several of them can read out basic JavaScript.

The following articles give details of how to make JavaScript accessible or provide alternatives:

Create Accessible AJAX

AJAX is a relatively new combination of older technologies. It uses CSS, XHTML, and JavaScript to update content on a page without reloading the entire page.

There is currently no known way of ensuring AJAX is entirely accessible on all browsers. The following points should therefore be considered:

  • Provide alternatives to AJAX until it is accessible
  • Tell users they need to have JavaScript enabled to view the page correctly
  • Consider if the use of AJAX is really necessary and is what your users want

Some useful tutorials include:

Screen readers users are likely to find Ajax information particularly difficult to interact with because information on the screen is refreshed regularly with Ajax, but there is no simple way to inform screen readers that content has changed. See the article Making AJAX work with screen readers http://juicystudio.com/article/making-ajax-work-with-screen-readers.php for further details.

Create Other Active Content

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Testing

For Accessible Flash

Navigate the Flash Movie with sound turned off, with only a keyboard, and listen to the Movie through a screen reader.

For Accessible Java

IBM have created detailed instructions http://www-03.ibm.com/able/guidelines/java/accessjava.html for testing Java for accessibility. Techniques include altering system accessibility options, manual checking and using screen readers.

For Accessible JavaScript and AJAX

Turn off JavaScript in your browser and check that your website is still usable. Listen to your website using a screen reader.

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Guidelines

Checkpoint 6.3 Ensure that pages are usable when scripts, applets, or other programmatic objects are turned off or not supported. If this is not possible, provide equivalent information on an alternative accessible page.

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