1251915 - AccessibleCaret cannot be dragged when pointer events is enabled

Status: RESOLVED FIXED

(Core :: DOM: Selection, defect)

Description

[Ting-Yu Lin [:TYLin] (PDT, UTC-7)]

When "dom.w3c_pointer_events.enabled" is true, AccessibleCaretEventHub will receives an eTouchCancel immediately after eTouchStart, which will be treated as if the user lifts his finger from the touch screen. Thus the subsequent eTouchMove events never be processed to move the caret.

[1] https://dxr.mozilla.org/mozilla-central/rev/5e0140b6d11821e0c2a2de25bc5431783f03380a/gfx/layers/apz/util/APZEventState.cpp#323,331

Comment 1

[Ting-Yu Lin [:TYLin] (PDT, UTC-7)]

Attachment: MozReview Request: Bug 1251915 - Ignore handling eTouchCancel events. r?roc

In my original design, I treat eTouchCancel to be like eTouchEnd for
ending a caret dragging procedure.

However when pointer events is enabled, it sents an eTouchCancel event
after the eTouchStart event whose primary usage is to be converted to
pointer events, which then cancels the normal caret dragging procedure.

Moreover, when pointer events is disabled, we don't get eTouchCancel
during a normal caret dragging scenario, so we don't really need to
handle eTouchCancel anyway.

Review commit: https://reviewboard.mozilla.org/r/37085/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/37085/

Comment 2

[Ting-Yu Lin [:TYLin] (PDT, UTC-7)]

Attachment: MozReview Request: Bug 1251915 - Correct AccessibleCaretEventHub coding style by clang-format. r?roc

This patch is generatedy by applying clang-format on
AccessibleCaretEventHub.cpp.

Review commit: https://reviewboard.mozilla.org/r/37091/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/37091/

Comment 3

[Ting-Yu Lin [:TYLin] (PDT, UTC-7)]

Comment on attachment 8724538 [details]
MozReview Request: Bug 1251915 - Ignore handling eTouchCancel events. r?roc

Review request updated; see interdiff: https://reviewboard.mozilla.org/r/37085/diff/1-2/

Comment 4

[Robert O'Callahan (:roc) (email my personal email if necessary)]

Comment on attachment 8724544 [details]
MozReview Request: Bug 1251915 - Correct AccessibleCaretEventHub coding style by clang-format. r?roc

https://reviewboard.mozilla.org/r/37091/#review33613

Comment 5

[Robert O'Callahan (:roc) (email my personal email if necessary)]

Comment on attachment 8724538 [details]
MozReview Request: Bug 1251915 - Ignore handling eTouchCancel events. r?roc

https://reviewboard.mozilla.org/r/37085/#review33615

Test?

Comment 6

[Ting-Yu Lin [:TYLin] (PDT, UTC-7)]

Comment on attachment 8724544 [details]
MozReview Request: Bug 1251915 - Correct AccessibleCaretEventHub coding style by clang-format. r?roc

Review request updated; see interdiff: https://reviewboard.mozilla.org/r/37091/diff/1-2/

Comment 7

[Ting-Yu Lin [:TYLin] (PDT, UTC-7)]

Comment on attachment 8724538 [details]
MozReview Request: Bug 1251915 - Ignore handling eTouchCancel events. r?roc

Review request updated; see interdiff: https://reviewboard.mozilla.org/r/37085/diff/2-3/

Comment 8

[Ting-Yu Lin [:TYLin] (PDT, UTC-7)]

https://reviewboard.mozilla.org/r/37085/#review33615

Add a gtest in revision 3 :)

Comment 9

[Pulsebot]

https://hg.mozilla.org/integration/mozilla-inbound/rev/51b5b9c96032
https://hg.mozilla.org/integration/mozilla-inbound/rev/50cb73a32974

Comment 10

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/51b5b9c96032
https://hg.mozilla.org/mozilla-central/rev/50cb73a32974