Website Accessibility

I'm currently developing a new website using ASP.NET and trying to get it to the highest level of accessibility W3C's WAI AAA.

I have a JavaScript scroller user control on one page that I need to ensure is accessible to everybody. Currently the majority of users will see a scrolling rows of images on screen. If a user has JavaScript disabled then this scroller gracefully becomes a scrolling div containing the images used in the scroller. If the user cannot view images then descriptions of all images in order are shown.

This is great but forgets one group - people who view websites normally through a well known browser but don't use a mouse (but still have JavaScript enabled). Therefore mouse events in JavaScript are useless. In my scroller control mouseover and mouseout events are used to track the direction the mouse is moving and therefore scroll in the direction desired.

To overcome this problem I have added a keyListener function which allows users to move the scroller using the arrow keys. However I am not 100% sure if the arrow keys play a vital part in keyboard navigation of a website and therefore if my scroller would interfere with this.

Basically should I use the arrow keys or choose other keys to manipulate the scroller?

DJ

The arrow keys are for scrolling. However, does your scrolling mechanism interfere with other things that need scrolling? Will, for example, an attempt to scroll the complete window (assuming it's small enough to require scrolling) also or (worse) instead scroll the images? Does your scrolling somehow interfere with the browser's own functions? (I know, for example, a page that catches keys in a way that Firefox's type-ahead-find doesn't work anymore.) Does Firefox's caret browsing still work? (Press F7 to activate it.) When exactly do you scroll the images? Whenever a key is pressed, or only if something inside that area has the keyboard focus? (Personally, I'd expect the latter, but I don't know about people who aren't as familiar with computers. My suggestion is that you get a bunch of people, some friends and family, and ask them to navigate your site without a mouse. If they can do it, you've passed. If they don't, ask them to navigate any other site without a mouse. If they can't do that either, then they're unsuitable testers; if they can, you screwed up.)

I think that about covers everything.