FWD: feedback on guidelines from DHTML developer

>From: Jeff Rouyer <rouyer@iex.net>
>To: Wendy A Chisholm <chisholm@trace.wisc.edu>
>Subject: Re: W3C WAI page author guidelines co-editor interested in your
>> For all images (IMG) provide alt-text (via the "alt" attribute).
>     Using the ALT tag for all images causes design conflicts in several
>ways. In older browsers the ALT tag was only shown when images are
>turned off. Now they appear automatically in a tool tip when you mouse
>flies over any image. These tool tips are platform specific and you cant
>control how they look, positioned or sized and look just ugly or come
>into visual conflict if you are building a custom interface.
>A great feature of DHTML is the ability to overlap transparent layers. I
>use this ability to build compound images and animations, meaning that
>several partial images may overlap to form a composite image.
>With DHTML, you can now load one large image but only allow a portion of
>that image to show through using a clipping window. I use this clipping
>often to simulate multiple button animations but using only one image.
>An ALT tag here would only be relevant once and not represent all the
>possible button displays. Using multiple images (even small sized) is
>prohibitive in that they are difficult to position in the DHTML world
>compared to a single image, and the fact it requires mutliple server
>socket connections to get numerous images which slows things down a lot and
>invites server lag.
>> A d-link (or invisible d-link). [Priority 1]
>     As a page designer control freak, I am very sensitive to adding any
>visual elements that may detract or simply ruin the design effect. An
>invisible d-link could work as long as there is a easy way of displaying
>that information avoiding having to create a description page, etc.
>Perhaps triggering a popup. The problem is that I only would want this
>option available to people who need it. In fact the ability to know if
>the user is using special aids, enhancements or is disabled in some way
>would be the biggest benefit to my design efforts. For example if a
>setting on the users browser said "Accessibility Level 1 Desired" and I
>can detect that setting with JavaScript, I then can dynamically adjust
>my page to suit the needs of that viewer, while others see the default
>designs. The fact that web sites can be adjusted on the fly on a visitor
>per visitor basis will allow for very strong accessibility
>customization. This could be accomplished now in my Guru site by
>including a checkbox to tell me what the user requirements are, then the
>page can be displayed. The problem is that most sites don't use a "gate
>keeper" page as their content is normally served up right away. Having
>the ability to check accessibility preference settings with JavaScript
>can be done before any page or content is displayed. This is similar to
>existing methods for checking browser versions, browser languages, and

>system. That information is then used to adjust the dynamic properties
>of the page while being viewed.
>> A.7. Ensure that moving, blinking, scrolling, or auto-updating objects
>or pages may be paused or frozen. [Priority 1] 
>     This becomes a big problem with advanced sites that use a lot of
>complex timing routines to perform animated events. Many of the animated
>events in my sites are a result of waiting for something to happen such
>as a loading an external page or preloading images. I use a lot of
>animated popup graphics that are also controlled by timers. After a
>certain period of time the pop-up will go away. Again things can be
>adjusted to be slower, bigger, brighter, only if I can detect what the
>user needs are in advance.
>-------------- Summary
>Browser support HTML 4.0 will be welcomed as a lot of useful techniques
>can be added such as long description. An alternate to ALT tag is
>needed to allow for design control. From a pure design stand point I am
>unwilling to create a default site design to accommodate everyone needs,
>but I am willing to modify the site on the fly using dynamic page
>methods if I can detect the users specific needs, devices, etc. This
>would be tremendous.

Received on Wednesday, 13 January 1999 10:28:48 UTC