Touch Accessibility (Guideline 2.5)

From Mobile Accessibility Task Force

Related Links

http://w3c.github.io/Mobile-A11y-TF-Note/TouchProposal_Discussion.html

https://lists.w3.org/Archives/Public/public-mobile-a11y-tf/2015Aug/0017.html

2015-09-10 discussion about Discussion on David's Proposals on Touch

Touch success criteria concern

Can't require everything available via touch

David recommendation

  • Anything that is touch functional can be accessed with touch with assistive tech turned on
  • May be more granular feedback from developers
  • Have to make sure that replaced gestures are not broken by authors
  • Pass-through gestures are more complicated - you make one gesture that puts AT in mode that passes the next command directly to the app

Discussion

  • The devices are touch specific – why do we need this? To ensure that all touch stuff will work with assistive technology turned on.
  • Not just talking about VoiceOver or talkback but all users.
  • There may be situations where touch may not be the best way to implement – making someone add touch where it has keyboard access probably doesn't make sense.
  • Difficult to see the next thing coming – didn't anticipate folks who are blind using touchscreens
  • Where does user agent come into play?
  • It has to work with one stack – natural would be system AT but if it does not, has to be something else
  • Tackle this in smaller pieces? Come up with success criteria first, then guideline?
    • Touch target size – success criteria level?
    • Guidelines don't have to be measurable. Guideline 2.5 Touch Accessible: Make it easier for users to operate touch functionality (Understanding)but should include pointer
  • If web application displayed on web Device make sure operable without external keyboard F12 – so broken for everybody, so not an accessibility issue. So it's good as it's worded.
  • Should be touch and pointer throughout, new document called pointer events
  • New ways of interacting – the next thing we don't anticipate – how does force touch work here, some people can't distinguish between light and hard press, duration. AT can take care that, but then where are other types of interaction like speech? Should be at the operating system level.

Changes to Note

  • Resolution: Agreement on "Guideline 2.5: Touch and Pointer Accessible: Make it easier for users to operate touch and pointer functionality." for the extension document
  • More discussion and/or discovery needed on force touch and what happens with folks who can't distinguish between light and hard press and duration

Proposed Guideline 2.5 Touch Accessible: Make all functionality available via touch.

2.5.1 Touch: All functionality of the content is operable through touch gestures.

OR

For pages and applications that support touch, all functionality of the content is operable through touch gestures with and without system assistive technology activated.

OR

For pages and applications that support touch, all functionality of the content is operable through touch gestures with and without system assistive technology activated, without relying on pass through gestures on the system (Level A)

2.5.2 Single Taps and Long Presses Revocable: Interface elements that require a single tap or a long press as input will only trigger the corresponding event when the finger is lifted inside that element. (Level A)

  • M003: Activating elements via the touchend event

2.5.3 Modified Touch: When touch input behavior is modified by built-in assistive technology, all functionality of the content is still operable through touch gestures. (Level A)

2.5.4 No Swipe Trap: When touch input behavior is modified by built-in assistive technology so that touch focus can be moved to a component of the page using swipe gestures, then focus can be moved away from that component using swipe gestures or the user is advised of the method for moving focus away. (Level A)

2.5.5 Touch Target Size: One dimension of any touch target measures at least 9 mm except when the user has reduced the default scale of content. (Level AA)

2.5.6 Touch Target Clearance: The center of each touch target has a distance of at least 9 mm from the center of any other touch target, except when the user has reduced the default scale of content. (Level AA)

  • M22: Spacing Between elements

Questions

  1. Are gestures the same as keyboard shortcuts?