1220199 - [B2GDroid] |scrollTo({behavior: 'smooth'...| doesn't work

Status: RESOLVED FIXED

(B2GDroid Graveyard :: General, defect)

Description

[Etienne Segonzac (:etienne)]

I've been told that APZ might only be working on the root scrollable area on Android, which will never work for Gaia since we have nested scrollable areas all the way down :)

Comment 1

[Etienne Segonzac (:etienne)]

Interestingly snapping is always instant.
We never smoothly scroll to the snapping point, once the snapping kicks in we instantly snap with no transition.

Comment 2

[Etienne Segonzac (:etienne)]

Looks like smooth scrolling in general doesn't work. Which points to the frames not being APZ enabled.

Comment 3

[Kartikaya Gupta (email:[e-mail])]

Are you building with --enable-android-apz in your mozconfig? I don't see that in the confvars for b2gdroid in-tree (but maybe I missed it). Maybe fabrice added that locally when he was building it?

Comment 4

[[:fabrice] Fabrice Desré]

It's enabled at https://mxr.mozilla.org/mozilla-central/source/mobile/android/b2gdroid/config/mozconfigs/common#46

Comment 5

[Etienne Segonzac (:etienne)]

(In reply to Etienne Segonzac (:etienne) from comment #2)
> Looks like smooth scrolling in general doesn't work. Which points to the
> frames not being APZ enabled.

This is still happening.
Pressing home to go back to the top of the homescreen, pressing home to close the utility tray etc...

All of these call |scrollTo({behavior: 'smooth'...| but we get no frame between the current position and the final position. It looks exactly like a "unsmooth" scrollTo().

Comment 6

[Kartikaya Gupta (email:[e-mail])]

It's probably running with these two prefs set to false:

http://mxr.mozilla.org/mozilla-central/source/modules/libpref/init/all.js?rev=6111fe8aca39#3651

because of the #ifdef ANDROID. If you set them to true in b2gdroid.js or wrap them in a MOZ_ANDROID_APZ or something it should work.

Comment 7

[[:fabrice] Fabrice Desré]

Attachment: smooth-scroll.patch

Works pretty well. Thanks Etienne for spotting that!

Comment 8

[Kartikaya Gupta (email:[e-mail])]

Comment on attachment 8687333 [details] [diff] [review]
smooth-scroll.patch

Review of attachment 8687333 [details] [diff] [review]:
-----------------------------------------------------------------

r+ for the scroll-behavior pref changes. I don't know about the raptor stuff...

Comment 9

[Pulsebot]

https://hg.mozilla.org/integration/b2g-inbound/rev/683059d91038

Comment 10

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

https://hg.mozilla.org/mozilla-central/rev/683059d91038