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From: Leo Smith
Date: Wed, Jul 25 2001 6:57AM
Subject: CSS-P, layers, links and accessibility
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Hi everyone,
I had a couple of questions regarding CSS absolute positioning and accessibility that I was hoping someone could clear up for me.
I am hoping to implement CSS-P (absolute positioning or what Dreamweaver calls layers) as much as possible in the site that I am presently redesigning, as I would very much like to get away from using tables for complex layouts.
I have read a good deal of literature about web accessibility and the fact that CSS should be used as much as possible for presentation and layout. The W3C techniques section for checkpoints 3.3 and 5.3 states that:
Layout, positioning, layering, and alignment should be done through style sheets (notably by using CSS floats and absolute positioning):
'float', 'position', 'top', 'right', 'bottom', 'left'. With these properties, the user can control the visual position of almost any element in a manner independent of where the element appears in the document. Authors should always design documents that make sense without style sheets (i.e., the document should be written in a "logical" order) and then apply style sheets to achieve visual effects.
However, I have found that when using layers, that links contained within them are not accessible via the tab key in Netscape 4x or 6, whether I use the <div> or <span> tag to code the layer.
For example:
<span id="Layer1" style="position:absolute; visibility:visible; z- index:1; left:50px; top:150px; width:100px"><a href="somewhere.htm">link</a></span>
or
<div id="Layer1" style="position:absolute; visibility:visible; z- index:1; left:50px; top:150px; width:100px"><a href="somewhere.htm">link</a></div>
neither of these allow links contained within them to be tabbed to when viewed in these browsers.
I have not read anything in the 508 or W3C guidelines that specifically says all links on a page should be accessible through the tab key, other than W3C Priority 3 specification 9.4 which states "create a logical tab order through links, form controls and objects".
Does the fact that Netscape 4x or 6 browsers do not allow access to links within a layer through the tab key mean that absolute positioning should be avoided?

Also, both the 508 and the W3C guidelines state that a document should be readable when style sheets are turned off.
Am I correct in assuming that inline styles do not come under "style sheet" in this directive?
That is, an inline style such as:
<span style="background-color:#ffffcc">hello everybody</span>
or like the layers above:
<div style="position:absolute; left:10px; top:50px; width:100px">The quick brown fox jumped over the log</div>
would not be included under this style sheet independence directive.

Thanks so much for your time and valuable input.
Best,
Leo.
Leo Smith
USM Office of Publications and Marketing
207-780-4774

From: Tom Dahm
Date: Wed, Jul 25 2001 9:09AM
Subject: Re: CSS-P, layers, links and accessibility
← Previous message | Next message →

Leo,
I'd advise you to stay away from CSS positioning. Netscape 4 doesn't support this reliably enough to make it a safe technology, and NN 4 still makes up about 15% of the browser market.
In general I'd be cautious about full implementation of the WAI guidelines, since they're based on the assumption that all browsers fully support the latest W3C standards.
Even though CSS isn't exactly a new standard, and the latest versions of NN and IE support it well, the presence of old browsers means you can't hang your hat on it yet. There are a lot of other accessibilty tags in the HTML standards that aren't widely supported yet (LABEL is a good example).
That's the main reason for the difference between the 508 requirements and the WAI guidelines. The WAI rules are based on the browser market as it should be; the 508 guidelines are based on the market as it really exists today.
Hope this helps.
Tom Dahm
NetMechanic, Inc.
"Power Tools for Your Web Site"
http://www.netmechanic.com
At 08:55 AM 7/25/01 -0400, you wrote:
Hi everyone,
I had a couple of questions regarding CSS absolute positioning and accessibility that I was hoping someone could clear up for me.
I am hoping to implement CSS-P (absolute positioning or what Dreamweaver calls layers) as much as possible in the site that I am presently redesigning, as I would very much like to get away from using tables for complex layouts.
I have read a good deal of literature about web accessibility and the fact that CSS should be used as much as possible for presentation and layout. The W3C techniques section for checkpoints 3.3 and 5.3 states that: Layout, positioning, layering, and alignment should be done through style sheets (notably by using CSS floats and absolute positioning):'float', 'position', 'top', 'right', 'bottom', 'left'. With these properties, the user can control the visual position of almost any element in a manner independent of where the element appears in the document. Authors should always design documents that make sense without style sheets (i.e., the document should be written in a "logical" order) and then apply style sheets to achieve visual effects.

However, I have found that when using layers, that links contained within them are not accessible via the tab key in Netscape 4x or 6, whether I use the <div> or <span> tag to code the layer.
For example:
<span id="Layer1" style="position:absolute; visibility:visible; z- index:1; left:50px; top:150px; width:100px"><a href="somewhere.htm">link</a></span>
or
<div id="Layer1" style="position:absolute; visibility:visible; z- index:1; left:50px; top:150px; width:100px"><a href="somewhere.htm">link</a></div>
neither of these allow links contained within them to be tabbed to when viewed in these browsers.
I have not read anything in the 508 or W3C guidelines that specifically says all links on a page should be accessible through the tab key, other than W3C Priority 3 specification 9.4 which states "create a logical tab order through links, form controls and objects".
Does the fact that Netscape 4x or 6 browsers do not allow access to links within a layer through the tab key mean that absolute positioning should be avoided?

Also, both the 508 and the W3C guidelines state that a document should be readable when style sheets are turned off.
Am I correct in assuming that inline styles do not come under "style sheet" in this directive?
That is, an inline style such as:
<span style="background-color:#ffffcc">hello everybody</span>
or like the layers above:
<div style="position:absolute; left:10px; top:50px; width:100px">The quick brown fox jumped over the log</div>
would not be included under this style sheet independence directive.

Thanks so much for your time and valuable input.
Best,
Leo.

Leo Smith USM Office of Publications and Marketing 207-780-4774

From: Leo Smith
Date: Wed, Jul 25 2001 9:32AM
Subject: Re: CSS-P, layers, links and accessibility
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Tom...thanks so much for your input.
I have actually used solely absolute positioning before to create
some websites (before I was designing for accessiblity), and have
had no other problems with NS4 - I use NS 4.03 as my test. This
tabbing issue is the only problem that I have encountered so far.
NS 4.03 seems to render layout perfectly using the position, left,
top, z-index, width, height and visibilty attributes. I also much
prefer to use CSS-P as it is a lot easier to manage and adjust than
tables for complex layouts, and I have found it to be more reliable
than complex tables for consistent layout across browsers
(especially with NS4, which has a number of nuances with table
layouts).
However, I would like to find a solution to this tabbing issue if one
exists....
Thanks Again..
Leo.

On 25 Jul 2001, at 10:07, Tom Dahm wrote:
Leo,

I'd advise you to stay away from CSS positioning. Netscape 4
doesn't support this reliably enough to make it a safe technology,
and NN 4 still makes up about 15% of the browser market. 

In general I'd be cautious about full implementation of the WAI
guidelines, since they're based on the assumption that all browsers
fully support the latest W3C standards. 

Even though CSS isn't exactly a new standard, and the latest
versions of NN and IE support it well, the presence of old
browsers means you can't hang your hat on it yet. There are a lot
of other accessibilty tags in the HTML standards that aren't
widely supported yet (LABEL is a good example). 

That's the main reason for the difference between the 508
requirements and the WAI guidelines. The WAI rules are based
on the browser market as it should be; the 508 guidelines are
based on the market as it really exists today. 

Hope this helps.

Tom Dahm
NetMechanic, Inc.
"Power Tools for Your Web Site"
http://www.netmechanic.com
At 08:55 AM 7/25/01 -0400, you wrote: 
Hi everyone, 

I had a couple of questions regarding absolute positioning and accessibility th
was hoping someone could clear up for me. 
I am hoping to implement CSS-P (absolute positioning or what Dreamweaver calls
layers) as much as possible in the site thI
am presently redesigning, as I would very
much like to get away from using tables for complex layouts. 

I have read a good deal of literature about web accessibility and the fact that CSS shd
be used as much as possible for presentatio and layout. The W3C techniques section for checkpoints 3.3 and 5.3 states that: Layout positioning, layering, and alignment
should be done through style sheets
(notably by using CSS floats and
absolute positioning):'float', 'position', 'top', 'right', 'bottom', 'left'. With thes properties, the user can control the visual position of almost any element in a
manner independent of where the
element appears in the document.
Authors should always design
documents that make sense without style
sheets (i.e., the document should be
written in a "logical" order) and then appl style sheets to achieve visual effects. 


However, I have found that when using layers, that
links contained within them are not accessible via
the tab key in Netscape 4x or 6, whether I use the
<div> or <span> tag to code the layer. 

For example: 

<span id="Layer1" style="position:absolute;
visibility:visible; z- index:1; left:50px; top:150px;
width:100px"><a
href="somewhere.htm">link</a></span> 

or 

<div id="Layer1" style="position:absolute;
visibility:visible; z- index:1; left:50px; top:150px;
width:100px"><a
href="somewhere.htm">link</a></div> 

neither of these allow links contained within them
to be tabbed to when viewed in these browsers. 

I have not read anything in the 508 or W3C
guidelines that specifically says all links on a page
should be accessible through the tab key, other
than W3C Priority 3 specification 9.4 which states
"create a logical tab order through links, form
controls and objects". 

Does the fact that Netscape 4x or 6 browsers do
not allow access to links within a layer through the
tab key mean that absolute positioning should be
avoided? 


Also, both the 508 and the W3C guidelines state
that a document should be readable when style
sheets are turned off. 
Am I correct in assuming that inline styles do not
come under "style sheet" in this directive? 

That is, an inline style such as: 
<span style="background-color:#ffffcc">hello
everybody</span> 

or like the layers above: 
<div style="position:absolute; left:10px; top:50px;
width:100px">The quick brown fox jumped over the
log</div> 

would not be included under this style sheet
independence directive. 


Thanks so much for your time and valuable input. 

Best, 

Leo. 

Leo Smith USM Office of Publications and Marketing 207-780-4774 


Leo Smith
USM Office of Publications and Marketing
207-780-4774

From: Jo Miller
Date: Wed, Jul 25 2001 9:36AM
Subject: Re: CSS-P, layers, links and accessibility
← Previous message | Next message →

At 10:07 -0500 7/25/01, Tom Dahm wrote:
>Leo,
>
>I'd advise you to stay away from CSS positioning. Netscape 4
>doesn't support this reliably enough to make it a safe technology,
>and NN 4 still makes up about 15% of the browser market.
I agree that Netscape's spotty and unpredictable support means that
CSS positioning should be used sparingly (at least for now) and
tested carefully on multiple platforms.
Note, by the way, that Netscape 4.x-6 will also prevent you from
tabbing to links and form fields within a table if you've used the
ALIGN attribute to position the table. The same is true if you use
ALIGN with images that are links; Netscape users will not be able to
tab to those links.
How important are Netscape's tabbing issues? That's a question worth
discussing, since tabbers (like me) do have the option of using IE.
Netscape for Mac doesn't support tabbing at all (and I don't think
Netscape/Linux does either, does it?).
--
Jo Miller
= EMAIL ADDRESS REMOVED =

From: Joycde Kennedy
Date: Wed, Jul 25 2001 10:04AM
Subject: Re: CSS-P, layers, links and accessibility
← Previous message | Next message →

If I could jump in (Hi, Leo...nice to meet you!) and put in a few
cents from an end-user point of view.
Although the monopolistic grip Microsoft has on the market bugs
me, the reality is that many of the folks that need and
use predictable tabbing are very often using IE 5 and not Netscape,
because the assistive technology they are using supports IE 5 and
not Netscape. Dragon NaturallySpeaking and Jaws come to mind.
Not that every effort should not be made to make pages accessible
in Netscape, but the reality is that Netscape has not made itself
amenable to interfacing well with assistive technology.
On 25 Jul 2001, at 11:30, Jo Miller < = EMAIL ADDRESS REMOVED = > wrote:
> At 10:07 -0500 7/25/01, Tom Dahm wrote:
> >Leo,
> >
> >I'd advise you to stay away from CSS positioning. Netscape 4
> >doesn't support this reliably enough to make it a safe technology,
> >and NN 4 still makes up about 15% of the browser market.
>
> I agree that Netscape's spotty and unpredictable support means that
> CSS positioning should be used sparingly (at least for now) and tested
> carefully on multiple platforms.
>
> Note, by the way, that Netscape 4.x-6 will also prevent you from
> tabbing to links and form fields within a table if you've used the
> ALIGN attribute to position the table. The same is true if you use
> ALIGN with images that are links; Netscape users will not be able to
> tab to those links.
>
> How important are Netscape's tabbing issues? That's a question worth
> discussing, since tabbers (like me) do have the option of using IE.
> Netscape for Mac doesn't support tabbing at all (and I don't think
> Netscape/Linux does either, does it?). -- Jo Miller = EMAIL ADDRESS REMOVED =
>

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Joyce Kennedy, ATP
Adaptive Technology Specialist
University of Southern Maine
144 Luther Bonney
Portland, ME 04104-9300
= EMAIL ADDRESS REMOVED =
(207)780-4029 / fax (207)780-4565
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

From: tklm@lineone.net
Date: Tue, Jul 31 2001 5:53AM
Subject: Re: CSS-P, layers links and accessibility
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Hi
I was wondering if anyone had sent Leo any solutions to the problem of not
being able to tab to links within DIVs in NS4. I'm using DIVs for layout,
and I'm particularly disappointed to discover that NS6 (actually I'm using
Mozilla 0.9.1) suffers the same problem. (You would have thought
accessibility was higher up the priority list for the Mozilla developers).
If anyone has any solutions or workarounds, I'd be interested to hear them.
John Farrie
Accessibility by Design
"Design for accessibility and everyone can benefit"
http://accessibilitybydesign.co.uk

From: Kynn Bartlett
Date: Tue, Jul 31 2001 9:17AM
Subject: Re: CSS-P, layers links and accessibility
← Previous message | No next message

At 05:53 AM 7/31/2001 , = EMAIL ADDRESS REMOVED = wrote:
>(You would have thought
>accessibility was higher up the priority list for the Mozilla developers).
It's not. There is little (if any) pressure exerted in the open-
source community to produce accessible software. There's some great
free or GPLed accessibility-related software out there, BUT it didn't
come about because of any sort of "pressure." This is different from
the case at, say, Sun or Microsoft or wherever, where they feel market
and economic and internal pressures to produce useful and accessible
stuff.
--Kynn
--
Kynn Bartlett < = EMAIL ADDRESS REMOVED = > http://kynn.com/
Technical Developer Liaison, Reef http://www.reef.com/
Chief Technologist, Idyll Mountain Internet http://idyllmtn.com/
Online Instructor, Accessible Web Design http://kynn.com/+d201