Silverlight and accessibility

About a year ago, a friend asked me how Microsoft planned to achieve world domination with Silverlight. Flash was already installed on practically every computer with a pulse, while Silverlight was yet another browser plugin asking users to install something they neither understood nor particularly wanted.

My guess was simple, cynical and unfortunately fairly obvious: Windows Update. Why waste time persuading people when you control the operating system?

And sure enough, yesterday Silverlight 1.0 began appearing as an optional Windows update, complete with browser plugins for Internet Explorer and Firefox. World domination probably requires a little more paperwork, but this is how these things start.

I first wrote about Silverlight back in March 2006, when it was still lumbering around under the spectacularly unsexy name WPF/E. Since then, Microsoft has given it a shiny new name, generated a respectable amount of hype and convinced considerably more people that they should care.

One problem remains, though: accessibility. Silverlight provides an Accessibility Object that can expose information to screen readers, which sounds promising until you examine what it actually does. Only the entire plugin area can receive focus, not the individual elements inside it. No individual focus means no useful tab order, poor keyboard navigation and generally the sort of experience that makes accessibility specialists reach quietly for the whisky. And if you’re using a Mac browser, the Accessibility Object isn’t available at all.

So yes, technically there is accessibility support. In much the same way that technically a deck chair is maritime equipment. Sites using Silverlight should also degrade gracefully when the plugin isn’t installed. One possible approach is SilverSpine, a framework by Todd Anthony Spatafore that allows you to provide an HTML version alongside the Silverlight experience. I’m generally suspicious of maintaining multiple versions of the same site. It tends to begin with noble intentions and end six months later with one version receiving all the attention while the other sits in a dark corner collecting dust and broken links. Still, it’s a start.

Accessibility and Rich Internet Applications have never exactly been a great romance. The same goes for SEO, and usability occasionally gets dragged into the alley and beaten up as well. To be fair, Silverlight isn’t necessarily worse than the other contenders in this particular circus.

There is some hope. Silverlight 2 is expected to support the same UI Automation accessibility model used by WPF, which should address at least some of these problems. Until then, Silverlight remains an impressive piece of technology with an awkward question hanging over it: What happens to the people who can’t, or won’t, experience it the way Microsoft intended?