867787 - [browser] can't scroll up/down if the user starts a scroll left/right on a scrollable element

Status: RESOLVED DUPLICATE of bug 898478

(Core :: Graphics: Layers, defect)

Description

[Julien Wajsberg [:julienw]]

STR:
* go to http://fr.m.wikipedia.org/wiki/Montbrison_%28Loire%29
* scroll down until "Localisation"
* try to scroll again (up or down) when the first touch is on the map

Expected:
* it's easy

Actual:
* the scroll up does not work if we start by scrolling left/right. The problem is that this can be done without trying.

In this case, the scrollable element can't be scrolled up or down, so I think that when the user try to scroll up/down the whole page should scroll.

If we try to make it more general, the page should scroll <direction> as soon as the element touched can't be scrolled <direction>, with <direction> is either up, down, left, right.

I haven't checked how it works on Android or even on Firefox Desktop with the mousewheel.

Comment 1

[Ben Francis [:benfrancis]]

I can reproduce this. I'm not sure if it's intentional but once you've panned left/right the scrollable element seems to swallow all the panning input so you can't pan up/down. It's fairly easy to work around for the user, but it is irritating.

Not sure where in the platform this bug should live.

Comment 2

[Shih-Chiang Chien [:schien] (UTC+8) (use ni? plz)]

BrowserElementPanning will lock the scrolling target if any panning takes effect. I think implementing axis lock can improve the user experience, however, we planned not to do so (see bug 824525). Maybe we need to re-evaluate about axis lock on B2G.

Comment 3

[Shih-Chiang Chien [:schien] (UTC+8) (use ni? plz)]

BTW, I tried this STR on iOS safari got the same behavior as FirefoxOS.

Comment 4

[Julien Wajsberg [:julienw]]

I come back to my proposed solution :

When the user tries to scroll <direction> an element, we should scroll <direction> that element first; then if that element can't be scrolled <direction> (because it's already at the end of the scroll), then try again with the nearest scrollable parent element.

Comment 5

[Julien Wajsberg [:julienw]]

Looks like a Layers bug after all.

Comment 6

[Botond Ballo [:botond]]

I can't reproduce this issue with latest gecko. I think the issue was fixed by my patch for bug 898478.

Julien, could you try again with latest gecko and see if you still experience this?

Comment 7

[Julien Wajsberg [:julienw]]

The main issue is fixed but the kinetic panning does not work when the touchstart is inside the map on the URL in comment 0. :)

Comment 8

[Milan Sreckovic [:milan] (needinfo for best results)]

Julien, let's open a separate bug for the kinetic panning scenario you mention so that we don't have multiple issues in this bug.

Comment 9

[Julien Wajsberg [:julienw]]

ok, I'll dupe this one then.