Re: let's bump to 10mm from 9mm

also remember that you are only making it useable by some people who need it a bit bigger.   Anyone needing it larger will not be covered.  

so this should be viewed as the MINIMUM standard for buttons to facilitate use by….


does anyone have an data as to what percentage of people with physical disabilities that this will help?  and how many not? 


g



> On Dec 18, 2015, at 11:33 AM, Patrick H. Lauke <redux@splintered.co.uk> wrote:
> 
> On 18/12/2015 17:09, Richards, Jan wrote:
>> It feels very strange to say that all things being equal (i.e. set to
>> user-agent default), that using the <button> alone (with no CSS)
>> could fail. So, based on some quick checks with how <button> is
>> rendered in a few browsers I revise my earlier suggestion to:
> 
> Let's not lose sight of what the original intent here is: making sure that controls etc are large enough so they can be comfortably/confidently used on a touchscreen by people of varying abilities.
> 
> Just doing a basic check of <button>, just on iPhone 5c (not breaking out my other devices for testing again), it seems that the default dimensions given to an empty button (so the smallest a default button would get) is around 4.5mm as measured on the physical screen. This is markedly too small to be used comfortably by anybody. As such, relying on browser defaults is not a viable option (the fact that those defaults may be inadequate is more of a discussion for UAAG, of course, if they also want to do some kind of touchscreen-specific extension/addition).
> 
>> 2.5.4 Touch Target Size: Touch targets have a diameter of at least
>> twice the height of capital letters in the user agent's default text
>> size.
> 
> As a de-facto standard, practically all browsers (including on mobile/tablet devices) have a default text size of 16px (and yes, CSS pixels, before anybody asks). So in essence, there's no difference from saying "twice the height of captial letters..." and, effectively, "32px" (which, btw, would be too small - on this iPhone5c that equates to just under 5mm as measured on the screen).
> 
> Considering that guides like Apple's HCI one, the BBC mobile guidelines, and others do actually define sizes in device/resolution independent units (be it Apple's "points", which equate to "CSS pixels", or similar), I'd still think there's no big problem in having the SC call specifically for a particular minimum size in CSS pixels.
> 
>> Then, all of the CSS unit measurements could then be techniques.  I
>> know that the default height of buttons on mobile browsers can't be
>> trusted to be 9mm, so this requirement is a lower bar than the
>> original wording, but I'm just trying to find something that will
>> work.
> 
> Do we want a lower bar, or something that actually addresses the issue it's trying to solve, though? Having a default button size of 4.5x4.5mm, or (if saying twice the default font size) 5x5mm is painfully small.
> 
>> Agreed, I just meant that defining a size with pixels can cause the
>> text inside the button to be cut-off when it is zoomed, causing
>> problems for 1.4.4 Resize text.
> 
> Sure, but any of those problems would then be failures of 1.4.4 and should not be a concern of this SC (and following the guidance of this SC would not necessarily result in failures of 1.4.4).
> 
> P
> -- 
> Patrick H. Lauke
> 
> www.splintered.co.uk | https://github.com/patrickhlauke
> http://flickr.com/photos/redux/ | http://redux.deviantart.com
> twitter: @patrick_h_lauke | skype: patrick_h_lauke
>

Received on Friday, 18 December 2015 17:54:48 UTC