Re: Rough draft of some success criteria for a extension guideline "Touch accessible"

On 17/08/2015 12:27, David MacDonald wrote:

>  >Patrick says: As it's not possible to recognise gestures when
> VoiceOver is enabled, as VO intercepts gestures for its own purposes
> (similar to how desktop AT intercept key presses) unless the user
> explicitly uses a pass-through gesture, does this imply that interfaces
> need to be made to also work just with an activation/double-tap ? i.e.,
> does double-tap count in this context as a "gesture"? If not, it's not
> technically possible for web pages to force pass-through (no equivalent
> to role="application" for desktop/keyboard handling)...
>
> David: VO uses gestures for its own purposes and then adds gestures to
> substitute for those it replaced i.e., VO 3 finger swipe= 1 finger
> swipe. I'm suggesting that everything that can be accomplished with VO
> off with gestures can be accomplished with VO on.

Not completely, though. If I build my own gesture recognition from basic 
principles (tracking the various touchstart/touchmove/touchend events), 
the only way that gesture can be passed on to the JS when VO is 
activated is if the user performs a pass-through gesture, followed by 
the actual gesture I'm detecting via JS. Technically, this means that 
yes, even VO users can make any arbitrary gesture detected via JS, but 
in practice, it's - in my mind - more akin to mouse-keys (in that yes, a 
keyboard user can nominally use any mouse-specific interface by using 
mouse keys on their keyboard, just as a touch-AT user can perform any 
custom gesture...but it's more of a last resort, rather than standard 
operation).

Also, not sure if Android/TalkBack, Windows Mobile/Narrator have these 
sorts of pass-through gestures (even for iOS/VO, it's badly 
documented...no mention of it that I could find on any official Apple 
sites).

In short, to me this still makes it lean more towards providing all 
functionality in other, more traditional ways (which would then also 
work for mobile/tablet users with an external keyboard/keyboard-like 
interface). Gestures can be like shortcuts for touch users, but should 
not replace more traditional buttons/widgets, IMHO. This may be a user 
setting perhaps? Choose if the interface should just rely on touch 
gestures, or provide additional focusable/actionable controls?

P
-- 
Patrick H. Lauke

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Received on Monday, 17 August 2015 11:48:40 UTC