816353 - Scroll-to-top and scroll-to-bottom gestures are easy to trigger accidentally while fling-scrolling

Status: RESOLVED FIXED

(Firefox for Metro Graveyard :: Input, defect)

Description

[Matt Brubeck (:mbrubeck)]

I frequently trigger swipe gesture commands (e.g. swipe to scroll to top or bottom of the page) by accident while I'm just trying to scroll quickly.

Can we switch to multi-finger swipes for these commands?  This would reduce the conflict with "fling" scrolling, and would be consistent with our support for trackpad gestures.

If we do change this, we'll need to change how these gesture events are detected and dispatched in our widget code.  (Maybe the event should have a property that counts the number of fingers on the screen.)

Comment 1

[Tim Abraldes [:TimAbraldes] [:tabraldes]]

I would love to ditch single-finger swipes for exactly the reason you mention.  Windows doesn't provide support for multi-finger swiping [1][2] but I think we could accomplish this by keeping a count of the number of different pointerIDs we see during a gesture.  Then when the gesture is complete and we determine that it is a swipe, we can verify that it had the correct number of fingers.

[1] http://social.msdn.microsoft.com/Forums/en-US/winappswithcsharp/thread/b9680637-4da5-4c69-9015-c32bb2d1686b
[2] http://social.msdn.microsoft.com/Forums/en-US/toolsforwinapps/thread/7fddff93-71f6-4871-85b5-2c8bd69344e2

Comment 2

[Jim Mathies [:jimm]]

This is an annoying bug, we need to test whether or not this can be tweaked through widget. We may also have other solutions to similar problems.

Comment 3

[Matt Brubeck (:mbrubeck)]

We might just want to remove the scroll-to-top and scroll-to-bottom gestures; they are not very discoverable anyway.  Other mobile browsers like Opera have nice discoverable UX for scrolling long distances.

Comment 4

[Matt Brubeck (:mbrubeck)]

Yuan agreed on IRC that we should just remove the swipe up/down gestures.  They are unintentional leftovers from XUL Fennec (where they did require multiple fingers).

Comment 5

[Matt Brubeck (:mbrubeck)]

Attachment: patch

This removes the vertical swipe gestures for now; we should file a separate bug to find a better way to support scrolling long distances.

Comment 6

[Tim Abraldes [:TimAbraldes] [:tabraldes]]

Comment on attachment 689440 [details] [diff] [review]
patch

Review of attachment 689440 [details] [diff] [review]:
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This seems fine as long as scrollContentToTop and scrollContentToBottom don't have any other consumers (keyboard shortcuts maybe?)

Comment 7

[Matt Brubeck (:mbrubeck)]

https://hg.mozilla.org/projects/elm/rev/aa9418a727e8

(In reply to Tim Abraldes (:tabraldes) from comment #6)
> This seems fine as long as scrollContentToTop and scrollContentToBottom
> don't have any other consumers (keyboard shortcuts maybe?)

Nope, no other callers.

Comment 8

[Matt Brubeck (:mbrubeck)]

Resolving bugs in the Firefox for Metro product that are fixed on the elm branch.  Sorry for the bugspam.  Search your email for "bugspam-elm" if you want to find and delete all of these messages at once.