Bug 200204

Summary:

Content in <iframe> should override "touch-action" set in embedding document

Product:

WebKit

Reporter:

Simon Fraser (smfr) <simon.fraser>

Component:

CSS

Assignee:

Nobody <webkit-unassigned>

Status:

RESOLVED FIXED

Severity:

Normal

CC:

commit-queue, graouts, koivisto, simon.fraser

Priority:

Keywords:

InRadar

Version:

WebKit Nightly Build

Hardware:

Unspecified

OS:

Unspecified

See Also:

https://bugs.webkit.org/show_bug.cgi?id=200205
https://bugs.webkit.org/show_bug.cgi?id=210041

Bug Depends on:

200853

Bug Blocks:

Attachments:

Description	Flags
Test	none
patch	none
alternative fix	none
patch	none

Simon Fraser (smfr)

Reported 2019-07-28 12:38:06 PDT

What should be the behavior of touch-action on an <iframe>? Should it override the touch-actions of the iframe contents or not?

Attachments
Test (650 bytes, text/html) 2019-08-16 01:24 PDT, Antoine Quint	no flags	Details
patch (4.67 KB, patch) 2019-08-16 05:04 PDT, Antti Koivisto	no flags	Details Formatted Diff Diff
alternative fix (4.97 KB, patch) 2019-08-17 00:30 PDT, Antti Koivisto	no flags	Details Formatted Diff Diff
patch (4.59 KB, patch) 2019-08-17 00:33 PDT, Antti Koivisto	no flags	Details Formatted Diff Diff
Show Obsolete (2) View All Add attachment proposed patch, testcase, etc.

Antoine Quint

Comment 1 2019-08-16 01:24:27 PDT

I would have expected them to, but the spec doesn't seem to say anything in that regard. Empirically, the attached test shows in the Chrome dev tools using Pixel 2 as the emulated device that scrollable content in an <iframe> does scroll when the top-level document has "touch-action: none" set.

Antoine Quint

Comment 2 2019-08-16 01:24:46 PDT

Created attachment 376484 [details] Test

Antti Koivisto

Comment 3 2019-08-16 04:57:13 PDT

<rdar://problem/54355249>

Antti Koivisto

Comment 4 2019-08-16 05:04:43 PDT

Created attachment 376493 [details] patch

Antti Koivisto

Comment 5 2019-08-16 06:07:11 PDT

(In reply to Antoine Quint from comment #1) > I would have expected them to, but the spec doesn't seem to say anything in > that regard. Empirically, the attached test shows in the Chrome dev tools > using Pixel 2 as the emulated device that scrollable content in an <iframe> > does scroll when the top-level document has "touch-action: none" set. I don't think spec is ambiguous about this: "A touch behavior is supported if it conforms to the touch-action property of each element between the hit tested element and its nearest ancestor with the default touch behavior (including both the hit tested element and the element with the default touch behavior)." With iframe content the "nearest ancestor with the default touch behavior" is the iframe. If there is no 'touch-action' set in any of the elements between the touch element and the iframe then default touch-action (auto) is applied, no matter what it is set in iframes ancestors.

Antti Koivisto

Comment 6 2019-08-16 06:18:17 PDT

Well, I suppose it is bit ambiguous what "nearest ancestor with the default touch behavior" exactly means for frame content as <iframe> is not a DOM ancestor of its content document. Whatever the interpretation is it doesn't affect this bug though.

WebKit Commit Bot

Comment 7 2019-08-16 08:48:09 PDT

Comment on attachment 376493 [details] patch Clearing flags on attachment: 376493 Committed r248772: <https://trac.webkit.org/changeset/248772>

WebKit Commit Bot

Comment 8 2019-08-16 08:48:10 PDT

All reviewed patches have been landed. Closing bug.

WebKit Commit Bot

Comment 9 2019-08-16 22:15:42 PDT

Re-opened since this is blocked by bug 200853

Antti Koivisto

Comment 10 2019-08-17 00:30:21 PDT

Created attachment 376598 [details] alternative fix Instead of generating the event region for frame top layer (the previous patch) simply treat the missing region as indicating touch-action:none when resolving touch-actions in UI process.

Antti Koivisto

Comment 11 2019-08-17 00:33:42 PDT

Created attachment 376599 [details] patch

WebKit Commit Bot

Comment 12 2019-08-17 01:50:19 PDT

Comment on attachment 376599 [details] patch Clearing flags on attachment: 376599 Committed r248819: <https://trac.webkit.org/changeset/248819>

WebKit Commit Bot

Comment 13 2019-08-17 01:50:21 PDT

All reviewed patches have been landed. Closing bug.

Note You need to log in before you can comment on or make changes to this bug.