[pointerevents] Add Element.hasPointerCapture API

RByers has just created a new issue for 

== Add Element.hasPointerCapture API ==
As [discussed at the 
 if  we end up going with the reduced hit-test model (#8) then there 
may be scenarios where some library will want behave differently 
depending on whether the pointer has been captured, without actually 
changing the capture itself.

For example, some analytics libraries track "user attention" by 
recording a log of the position and interesting underlying elements of
 every pointer.  If touch starts capturing implicitly, it's possible 
the stats from such a library could be broken.  To mitigate this they 
might want to do their own `elementFromPoint` hit-test on 
`pointermove` without actually doing a `releasePointerCapture`.

Really this is a more generic problem that in composition scenarios 
one library may want to know if the pointer is currently captured or 
not.  It's not clear how important this is, but it seems to make a lot
 of sense to have an API like `Element.hasPointerCapture(pointerId)` 
which pointer event listeners could check on the target of the event.

Please view or discuss this issue at 
https://github.com/w3c/pointerevents/issues/121 using your GitHub 

Received on Thursday, 28 July 2016 17:33:49 UTC