Re: [selectors4] Adding User Action Pseudo-classes for touch

If I may ask, are there a lot of cases where this would be better than just
having touch browsers display the :active state for touched elements?

—Zachary “Gamer_Z.” Yaro
On Nov 17, 2012 12:18 PM, "Wes Johnston" <wjohnston@mozilla.com> wrote:

> It would be nice when interacting with web pages in touch or pen based
> environments if there were easy ways to style objects based on whether they
> are currently being touched or perhaps if they were touched in the last
> touch session on the screen. I'd like to propose two potential selectors
> for these situations:
>
> 1.) :touching for when an element is actively being touched on the screen.
> Unlike targets in the touchevents spec, this should actively change as the
> user moves their finger on the screen. As soon as a user lifts their finger
> from the screen these selectors would no longer match. One potential use
> case for this is something like an onscreen keyboard where you want the
> keys to light up as the user drags their finger on the keyboard. This could
> also be helpful as a means of providing quick feedback about what is being
> touched on screen (i.e. tap highlights).
>
> 2.) :touched to match the elements that are actively being touched, or
> elements that were being touched the last time a finger was on the screen.
> The use case I want to address here are things like drop down menus, where
> you would likely want them to remain visible on screen even after the users
> finger has been lifted, but to disappear if the user touches outside the
> menu. The selector should be removed as soon as another touch starts, ends
> or moves on the document (i.e. if two fingers are on the screen and one is
> lifted,  the selector should match until the second finger moves or another
> finger touches the document).
>
> In both cases, the selectors should stop matching if the system starts
> performing any system actions on the page (such as scrolling).
>
> Apologies if I'm doing something incorrectly here. Its my first email to a
> working group.
>
> Thoughts?
> - Wes
>
>