Re: Re: question: fixed vs. liquid layout

Maurizio Boscarol wrote:
>So my point was not really on deciding which text-line-lenght is 
>optimal, cause that can be tricky, but if a fixed layout can be seen as 
>an accessibility impairment. And at which conditions: are there some 
>"good fixed-layout practice"? Some sites (as alistapart) use a fixed 
>measure (597px) that work at any screen resolution, even if with 
>different usability... Some others (like Marco's layout, as I can see: 
>it uses 700px) don't. Is that important for accessibility?

I think that a "locked" measure of 597px in a two columns layout is a bad solution from the point of view of accessibility. Increasing text size of only two steps can produce with Firefox 0.9 a serious problem of readability, as you can see looking at this screenshot, captured from Alistapart.com: http://www.diodati.org/bpl/2004/prove/ala.gif .

Generally speaking I think that locking the containing blocks of a page can be a problem for accessibility everytime there is a multicolumn layout, in which  you can't increase text size without overlapping part of the content over another part. Of course, increasing zoom factor will unavoidably cause soon or later some overlapping. So it would be desirable in my opinion that WCAG 2.0 define precisely a range in which increasing text size must not produce any overlapping of content (I propose a measure between 150% and 200% of default text size).

A web page in which containing blocks can be automatically rescaled to fit user agents available window has a great advantage in comparison with a web page which containing blocks size can't be rescaled: it can be viewed with any kind of screen device (handhelds for example), no matter what available horizontal screen size is.

I think that for sighted users with low vision the best solution is a "liquid" layout with only one column and wide margins around it. Very often this is not the best choice from the designer's point of view. A reasonable way out could be a link at the very top of the page allowing users to choose between a simple column layout and a two or more columns layout. For example there are about two years I use such a kind of mechanism (the link between two small red arrows at the top of http://www.diodati.org/index.asp ) on the home page of my site. During this period I received many positive feedbacks from users: sighted users with normal vision that look at the page from a big display use the default two columns layout; low vision users and handheld users can easily switch to the alternative single column layout (under certain conditions the second column moves itself under the first, while the user has to do nothing). I think such a kind of developing solution allows to address!
  the needs of visually impaired users as the needs of designers aiming at creating pages that look beautiful and attractive. While choosing between different styles "tailored" on different media types (e.g. screen, print, handheld) is independent from the will of the user, the system I propose allows users to choose the number of columns according only to their actual preferences, indipendently from the kind of screen device they are using in a certain moment.

Michele Diodati
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michele@diodati.org
http://www.diodati.org
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P.S.: I apologize for my not perfect English.

Received on Saturday, 19 June 2004 09:34:34 UTC