Web Accessibility

Adobe AIR is a cross-operating system platform that allows developers to leverage their existing web development skills in HTML, Ajax, XML, Flash and Flex to build and deploy Rich Internet Applications for the desktop.

Christian asks what would be the open-source equivalent of AIR? XUL says Ian. Christian says that AIR is built on HTML, CSS and JavaScript so once the player gets keyboard access it will be quite accessible. Ian responds that he looked on the Adobe site for accessibility info on AIR and the fact that he found nothing scared him.

3. Easy conversion of existing Flex or HTML applications. It’s the same basic runtime. In the case of HTML, AIR apps rely on WebKit, the core component in Apple’s Safari web browser.

7. Rich design and multimedia. This is Flash, so ideal for highly customized UIs, animation, sound and video. Adobe is proving the point by creating a media player built with AIR. Existing Flash developers can easily use their skills to build AIR applications.

4. Proprietary technology. AIR applications depend on Adobe’s runtime.

We considered a few approaches, but decided to grow our new widget out of Adobe Flex and Adobe AIR. This is firstly because these tools met our requirements to work cross-platform and deliver the desktop experience we wanted, and also because they linked up with in-house skills in the team which manages them, making them simpler to manage.

BBC Future Media & Technology's pilot widget application BBC LiveUpdate uses the Adobe AIR runtime, which is dependent on users downloading and installing a plugin to their desktop, but which unfortunately does not currently support screenreaders (or other software which relies on the Microsoft Active Accessibility layer for assistive technologies). We're working with Adobe to make tools built with AIR more accessible than current products wherever possible and are committed to delivering accessible services. As this is a beta product, there are also other limitations in how much we have been able to establish accessibility support in the following areas:Colour contrast cannot be alteredText size cannot be alteredLacks consistent alt textLacks Title attributesIs not entirely tabbable.

Shorter line lengths and narrower text columns make reading easier.

Consider setting a percentage width for text areas and set the margins to “0 auto” via CSS. The page side margins will then increase proportionately on wider screens.

Most browsers have a default line-height of around 1em. This normally results in closely packed lines of text. Increasing the line-height to around 1.3em immediately makes longer lines of text easier to read. Likewise, ensure that paragraphs are visibly separated. Don’t be afraid of white space. Use it to enhance readability.

“Ensure that foreground and background color combinations provide sufficient contrast when viewed by someone having color deficits or when viewed on a black and white screen.”

Scoptic Sensitivity Syndrome

can make high contrast text difficult to read because the words seem to constantly move on the page.

The specific needs of dyslexics tend to be overshadowed by the more widely understood needs of the visually impaired. Unfortunately, design decisions that benefit the latter group tend create problems for the former. This is never more evident than in so-called “accessible” text only pages with their emphasis on high contrast and complete lack of images and colour.

What is Dyslexia?

The word “dyslexia” can be broken down into two parts: “Dys” meaning poor and “lexia” meaning language. Thus dyslexics have difficulties with words. Current theories suggest that

The BBC has developed a script called Betsie, which will convert pages to plain HTML.

There can be a fine line between enabling and excluding technology. All it takes is some careless HTML, the addition of a few unsupported images and some multimedia frills, and entire web sites can disappear from view for substantial numbers of users.

WysiHat is a WYSIWYG JavaScript framework that provides an extensible foundation to design your own rich text editor. WysiHat stays out of your way and leaves the UI design to you. Although WysiHat lets you get up and running with a few lines of code, the focus is on letting you customize it. We are giving developers early access to the project while we continue to work out the remaining issues. Note: It’s extremely early. Contributors are welcome so please check out the project on GitHub and send us your feedback.

In Boagworld podcast episode 130, I discovered that in order to help test web accessibility, Paul Boag wears glasses (that he doesn't need) and gloves and attempts to navigate through a site. Excellent idea!In order to better understand [the elderly's] experience I have bought a pair to ski gloves and some reading glasses (I don't need reading glasses). Every now and again, I surf the site I am designing wearing both the glasses and gloves. The glasses make the screen hard to read while the gloves hamper my use of the mouse and the keyboard. There is nothing more frustrating than trying to select something from a drop down menu wearing ski gloves!

One of the things that have long irritated me about HTML is the restriction on what elements are allowed inside lists. The specs for both HTML 4 and 5 allow only li for ul, ol, and only dt and dd are allowed inside dl definition lists. I’d like to expand that to allow h1…h6, section and div.