RE: Horizontal scrolling & reflow

My thought is whether it is essential?   A short English paragraph could scroll horizontally and I sometimes see this one part of a page scroll but other parts do not.   One horizontally scrolling paragraph scrolling in English remains a problem for the reflow SC in my opinion.

However, I understand that there are some controls like carousels that display multiple items on-screen at once that allow you to scroll horizontally – like those used for video and game titles on streaming services.   In this case the individual pieces fit on the screen but the control as a whole scrolls additional content horizontally.  This seems like it fits in the essential exception.

Jonathan

From: Alastair Campbell <acampbell@nomensa.com>
Sent: Tuesday, September 4, 2018 12:47 PM
To: David MacDonald <david@can-adapt.com>
Cc: WCAG list <w3c-wai-gl@w3.org>
Subject: Horizontal scrolling & reflow

Hi David,

We had a little side-bar on a call around reflow & horizontal scrolling.

The context was whether you can have a horizontally scrolling nav-bar in an otherwise vertically scrolling page.

I’m struggling to find an example now, the client instance is pre-live, the other instance I could think of was theguardian.co.uk, but they’ve changed it now (I wonder why).

Oh, I found it using the wayback machine, look at the top nav on here:
https://web.archive.org/web/20150630123506/http://www.theguardian.com/uk<https://web.archive.org/web/20150630123506/http:/www.theguardian.com/uk>

If you have a touch-pad, that bit of content scrolls horizontally.

My read of the Reflow SC is that it applies to ‘content’, rather than pages (which was intentional):
Content can be presented without loss of information or functionality, and without requiring scrolling in two dimensions for:


  *   Vertical scrolling content at a width equivalent to 320 CSS pixels;

·         Horizontal scrolling content at a height equivalent to 256 CSS pixels.

I.e. if a bit of a page scrolls horizontally, that’s ok if it fits within 256px high. However, if that same bit of content requires scrolling in both directions, it fails that SC.

That bit of content does not require scrolling vertically, but does horizontally.

The same will apply on Korean / Japanese pages with a mix of vertical and horizontally read text-blocks. (I say “will” because it is only really becoming possible to do in browsers natively quite recently.)

For those mixed-content pages you would zoom in and blocks would reflow, but some of them could scroll vertically, and some horizontally.

Does that make sense?

Kind regards,

-Alastair

--

www.nomensa.com<http://www.nomensa.com/> / @alastc