1070851 - [Touch Caret] Make touch caret respect argument 'withCaret' of snapshotWindow()

Status: RESOLVED FIXED

(Core :: Layout, defect)

Description

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

When calling snapshotWindow(win, withCaret) [1] in javascript, we can pass 'false' in the 2nd argument to avoid snapshot caret. However, touch caret will always be captured in the snapshot. It will be better to make touch caret respect this argument as caret did.

[1] http://hg.mozilla.org/mozilla-central/file/5bd6e09f074e/testing/mochitest/tests/SimpleTest/WindowSnapshot.js#l11

Comment 1

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

Hi Robert,

It seems that nsCaret avoid adding itself in the snapshot by early return in [1]. But touch caret is an anonymous frame under canvas frame. Any similar trick we could do to avoid displaying touch caret? Would you please give me some hints? Thanks.

[1] http://hg.mozilla.org/mozilla-central/file/5bd6e09f074e/layout/base/nsDisplayList.cpp#l957

Comment 2

[Mats Palmgren (inactive)]

You can probably just exclude the kid frame(s) for the touch caret for that case,
something like this:
 if (aBuilder->mBuildCaret || kid->GetContent() != mTouchCaretElement) {
   BuildDisplayListForChild(...);
 }
here:
http://mxr.mozilla.org/mozilla-central/source/layout/generic/nsCanvasFrame.cpp#418

Comment 3

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

Mats, thank you for providing the solution!

Comment 4

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

Attachment: Make touch caret respect snapshotWindow().

Avoid capture touch caret when the argument 'withCaret' is false in
snapshotWindow().

Comment 5

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

With the following CSS, I still got blue glow shown when focusing the input on B2G desktop and emulator. That's why the try failed.

input, textarea, div {
  background: none;
  outline: none;
}

Try result:
https://tbpl.mozilla.org/?tree=Try&rev=a6763c38622a

Comment 6

[Mats Palmgren (inactive)]

Does adding -moz-appearance:none; to the above style rule help?

Comment 7

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

Attachment: Make touch caret respect snapshotWindow(). r=roc (v2, carry r+)

Adding "-moz-appearance:none;" does not make any difference. I'll add "border: none;" to the style rule.

Try result:
https://tbpl.mozilla.org/?tree=Try&rev=7ee274c48684

Comment 8

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/f2441dd1b0a9

Comment 9

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/f2441dd1b0a9