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Archive for the 'Accessibility' Category

Accessible Flash Oxymoron? (FITC 2007)

Posted by Brett Tackaberry on April 24th, 2007 Comments Comments Off

Speaker: Niqui Merret

Contrary to popular belief, making a Flash movie accessible to a wider selection of users does not require cartwheels and back flips. A few basic usability and accessibility considerations can take your movie to the next level and reach a wider audience. The most basic step of embedding a SWF into a page incorrectly could cause a screen-reader to hang.

This session will take a cause and effect look at accessibility covering a selection of common problems and possible solutions. Niqui will cover visual, audio, mobility and cognitive disabilities and demonstrate how Flash can help or hinder access.

Notes:

Any information provided along a timeline should include synchronized text based description such as captions accompanying a video. For exmaple, weebls toons have captions.

Accessibility in the real world: no technology can be 100% accessible to all users. Level accesibility is directly proportional to level of effort put in.

Barriers to accessibility: technology (flash, browser, screen reader), developer (interface designer, programmers, copyrighters). Content developers cause barriers by not being aware of accessibility considerations.

Technology - Flash player interfaces with screen readers and keyboard well. Focus (big yellow box around object) is clear to user and focus is made available and is fed through to assistive technology.

Standards and guidelines? Current documentation is difficult to comprehend and digest. The key is to understand the user - its not a case of understanding rules and guides.

Simple tests. Take away the mouse and attempt to follow similar paths.

Simple disability categories. Visual (vision, colour blindness, etc). Audio (lack or partial). Motor (hands and holding). Cognitive (understanding).

Screen readers. Needs to gain access and report back to assistive technology. Not fully integrated with OS and sometimes unreliable - they are stuck in the middle of a chain of information.

Tips for flash: set the name of buttons; specify the reading order; avoid using wmode(!); and, test with screen reader and Microsoft Active Accessibility 2.0 Software Development Kit Tools. Tab index (found on accessibility panel in flash) is very useful in providing proper experience in flash - note this only applies to dynamic text fields. Flash also provides ability to program shortcuts for elements.

Tip: put tab index right on mockups.

As compared to AJAX, flash accessibility can send screen updates to the screen reader. HTML pages are treated as linear and do not send updates to the screen reader.

Microsoft Active Accessibility Tools allow deveoper to view the screen reader output in realtime.

On windows, OS contrast adjustment does not affect flash movies. On Mac, adjusting contrast settings affects the colours on the screen. Another possibility is to provide accessibility controls that allows the user to adjust the contrast - the flash object in turn adjusts the colour scheme in the movie.

Font size controls in browser do not affect flash movies. However, a particular approach (see Text-Resize Detection), is to listen to when a user adjusts the font size n the browser, and using javascript, pass that information back into the flash movie.

The creators of SWFObject and UFO have are working on SWFfix.

Keep in mind: Progressive enhancement != accessibility.

Also see: Adobe DevNet