[pointerevents] touch-action: scroll || scroll-x || scroll-y

appsforartists has just created a new issue for https://github.com/w3c/pointerevents:

== touch-action: scroll || scroll-x || scroll-y ==
A common interaction pattern that is not well-addressed by the pointer events spec is overscroll; that is, trying to scroll beyond the bounds of a scroll pane.  For instance, dragging a message in Inbox adjusts the scroll position until it's 0.  Dragging further will begin a gesture to close the message (while leaving scroll position at 0).  Another common example is pull-to-reload.  These interactions aren't straightforward to achieve with the current spec.

Would it be possible to introduce a new `touch-action` mode and behaves like `pan-{x,y}` does now, except it sends pointer events for overscroll?

- `scrollY = 100`
- User places finger at `{ 200, 200 }` and drags finger down by 110px
- For the first 100px, scrolling happens normally.  No pointer events are dispatched.
- When the user scrolls past `scrollY === 0`, `pointerdown` is dispatched with `{ pageX: 200, pageY: 300 }`
- `pointermove` is dispatched every frame until the pointer is lifted.
- `pointerup` is dispatched at `{ pageX: 200, pageY: 310 }`

Please view or discuss this issue at https://github.com/w3c/pointerevents/issues/211 using your GitHub account

Received on Thursday, 25 May 2017 02:59:23 UTC