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Re: media:Fw: Accessible Websites -- Making Sure That All Your Visitors Can Access All Your Site

From: David Woolley <david@djwhome.demon.co.uk>
Date: Sat, 19 Jan 2002 11:27:01 +0000 (GMT)
Message-Id: <200201191127.g0JBR1V01733@djwhome.demon.co.uk>
To: w3c-wai-ig@w3.org
> 1. Make sure you have "alt" tags for every image.  If a screen-reading

I wish people would use proper terminology.  There are no alt tags, only
alt attributes.

"All" could imply that alt="" was not acceptable.

> &lt;img src="frank.gif"  ALT="Picture of Frank Jones, our

"Picture" is a current hot potato!

> it reports to the user exactly what the image is. (Note: this is also

I think I could actually claim that there is a consensus that this
is wrong.  It's the message of the image that is important.

>     &lt;img src="frank.gif" ALT="see d-link for long description"&gt;

This forces the user to go out of line.

> planned.  Most "text to speech" readers read across a page, rather than

Pure text to speech tools are likely to be used with browser like Lynx
which will not exhibit the effect described.

(How do pure text to speech tools work on windowing systems - I would
have thought that they would have to, at least, use cut and paste
interfaces, as the normal windowing system design has the window
manager only know about the bitmapped form of the screen and delegate
to applications to recreate this from their private document data
structures, when a repaint is needed.  If they use cut and paste
interfaces, they ought to read the table the right way anyway.)

> This table will be read as "Activities Requirements....swimming and a
> red
> cross card boating without or other proof or supervision qualification"
> 
> There are several accessible design strategies to help with this
> problem.
> First, try to make sure that each table element has one and only one
> line

Loose terminology makes nonsense of this.  I think they mean "cell", or
possibly "table data or heading element".

This is also generally not possible because you can't control font sizes
and window widths.

> of text; it can also help to rearrange the table so that the headings
> go
> down the left column, and content down the right.

I would think that it was rather rare to have tables with only
one header and only one detail row, anyway.  Even from a purely visual
point of view, they are likely to force scrolling when a DL structure
or a two column design would be more natural.  

> 3. Bypass Repetitive Navigation Links. Well designed sites generally
> include a navigation bar at the top, or down the side of every page.

But he's just said that one should not have multi-line table (cells).
A left hand navigation bar will cause problems in pure text to speech
systems on any browser that successfully reconstructs this layout!
(For the reasons given above, this may be a non-issue.)

For browsers that give the linearised order, both CSS-positioning,
and the current tables fallback, can put the left hand navigation bar
to the end of the document, which is a much better place for search
engines, as well.

It's not really possible to back fill top panels with tables and
CSS Positioning (and frames!) can't properly cope with font size
and window width overrides.

> this is to insert a 1 pixel by 1 pixel gif, with an alt tag "Bypass

Hiding the bypass is bound to be controversial.  However what really
irritates me is an attempt to hide, or tone down almost to the point
of hiding, links to text only and low graphics alternative pages.
I may will often use them even in GUI browsers.

> navigation bar", that includes a link to an anchor further down the

Anything that puts text before the, hopefully front loaded, first 
paragraph of the real content of the page, is bad for those search
engines that return the start of the page as the description. There
is a danger that this will become almost as common as "you need to upgrade"
as the summary of a page in search results.

However, if you are doing so, it seems to me that this wording is
overly technical - one is going to the start of the main text.

(Advertising issues get in here:  sites paid for by third party advertising
don't actually want people to skip to the main text!)

>  Instead, do use
>  &lt;a href="index.shtml"&gt;jump back to our home page&lt;/a&gt;

Provided that links are clearly identified (and unfortunately one of
the major design games is hiding the links!) it should not be
necessary to have link marker words, like "jump" or "click". 

Also, "back" assumes the no-deep linking model of web sites.  On a
well designed site, what is much more likely to happen is that someone
comes in at the page from a search engine, or external link, decides the
page is useful, and wants to know more about the site, so wants to go
up the hierarchy, so, if you really do have to have tell people, in gory
detail, how hypertext works, "up to" is probably better than "back to".
In the past, a technical user could trim back the URL, but nowadays,
a lot of sites have forgotten the meaning of index in index.html and
simply return 403 Forbidden.

For these basic Up, Next, etc. links, one should also include them
as Link elements.  Lynx and recent versions of Mozilla support them.
Unfortuanately Mozilla doesn't turn on the relevant navigation bar by
default, even though it can be configured only to show on pages with at
least one such link element, as well as permanently.

At the very least, you need one level up and organisation home page links, 
but a common good practice is actually to include the complete path from
the home page, so that you can skip up multiple levels.

(The use of server parsed HTML for essentially static pages should be
discouraged.)
Received on Saturday, 19 January 2002 06:59:49 GMT

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