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Re: Developer Responsibility and Responsive Design

From: Alastair Campbell <acampbell@nomensa.com>
Date: Mon, 14 Mar 2016 09:25:53 +0000
To: Wayne Dick <wayneedick@gmail.com>, public-low-vision-a11y-tf <public-low-vision-a11y-tf@w3.org>
Message-ID: <42496F8C-E183-47EC-91F8-8EC0AE51ED2F@nomensa.com>
Hi Wayne,

I generally agree with that, I would just note that you could structure it the other way around.

HTML is one-dimensional by default and with no styling it will be a linear presentation that has almost no limit on zooming. It is adding layout that screws things up from a zooming/text size point of view!

RWD enables a developer to change the layout based on the available width/height, and it is good practice to do that from mobile upward, rather than desktop downwards (a bit like progressive enhancement, you add to the layouts as the space increases).

I agree that WCAG shouldn’t demand a prescribed method, but you could update the WCAG docs based on the user agent method [1].

For example, a web page would pass if you could:

  1.  Zoom to 200% with no horizontal scrolling or loss of functionality.
  2.  Increase text-sizing to 200% without loosing content or functionality.

The first of those is easily achievable with RWD, the second is essentially the non-responsive / legacy version. You could also increase the amount of zoom (e.g. to 300%) as it is not a hardship to achieve that with RWD.

The normative text could be interpreted as that if the examples and test procedure were adjusted.

However, I think we would need to work with the mobile task force to define a maximum effective zoom. On desktop there is an effective minimum size supported by desktop browsers of around 300px wide, so if your screen resolution is 1024px, you can zoom in around 340%, if you have a 1600px wide screen you can zoom in around 500%. (You can zoom more, but you’ll probably get horizontal scrolling.)

Currently if you are on a mobile sized screen & browser then zooming “fails” the above test immediately as you get horizontal scrolling, which I would argue is a user-agent problem [2].

Kind regards,


1] https://alastairc.ac/2013/08/browser-zoom-great-for-accessibility/#comment-165796

2] https://alastairc.ac/2015/10/zoom-for-fixed-and-responsive-sites/

From: Wayne Dick <wayneedick@gmail.com<mailto:wayneedick@gmail.com>>
Date: Saturday, 12 March 2016 at 20:24
To: public-low-vision-a11y-tf <public-low-vision-a11y-tf@w3.org<mailto:public-low-vision-a11y-tf@w3.org>>
Subject: Developer Responsibility and Responsive Design
Resent-From: <public-low-vision-a11y-tf@w3.org<mailto:public-low-vision-a11y-tf@w3.org>>
Resent-Date: Saturday, 12 March 2016 at 20:25

Opinion form Wayne
We acknowledge that developers must organize their content so that screen readers can interpret content programmatically. The objective is to transform a two-dimensional presentation of content (the page) into a one-dimensional presentation (speech).
What seems to be difficult for many in the accessibility community to appreciate is that developers should have the responsibility to structure their content so that a different two-dimensional presentation can be constructed programmatically.
Responsive design is an authoring technique that proves that flexible organization of web content can be achieved that supports critical transformations that are needed by people with low vision. Specifically, RWD has proven that content can be structured so that it can support, linearized presentation and enlargement of up to 700% to 800% programmatically. Thus two of the most difficult technical issues facing people with low vision have been solved. We know this can be done, and it is needed by a very large class of people with disabilities.
I would never claim that web developers and web application developers should be forced use responsive design, but I do believe strongly that to achieve standards compliance, developers should provide content that can be linearized and enlarged to therapeutically effective levels programmatically. Also, by programmatically deterministic in this context I mean parse level access. That means that agents like CSS and other entities that depend on syntax directed translation can produce the necessary transformation of normal two-dimensional presentation to a user centered two-dimensional presentation of the web page. The web developers do not need to create the user centered presentations; they just need to create content that enables assistive technology that can do the job.
Requiring developers to use RWD would be to prescribe an accommodation. Requiring developers to structure documents so responsive transformations are possible is just as reasonable as asking developers to structure content so that screen reading is possible. It would be to require developers to make content fully accessible.

Received on Monday, 14 March 2016 09:26:24 UTC

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