1444572 - [GTK][uim] Dispatch fake "keydown" and "keyup" events if active IM uses key snooper and send some preedit signals to us

Status: RESOLVED FIXED

(Core :: Widget: Gtk, enhancement)

Description

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

At least UIM which is really old IM but still is default IM of Debian 9.x, IM may use key snooper to handle key events *before* applications. In this case, we won't receive native key events if IME consumes key events for composition.  Therefore, if we detect key snooper mode of each IM, we should dispatch fake keydown and keyup events whose keyCode value is DOM_VK_PROCESSKEY, key value is KEY_NAME_INDEX_Process and code value is "unidentified".

Comment 1

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=c917122a22904aae086e87915f4c4b330b2de464

Comment 2

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

Attachment: Bug 1444572 - IMContextWrapper should dispatch fake eKeyDown event during composition if active IM is uim

uim is an old IM which uses key snooper to listen to key events rather than
via filter key event API which should be called by applications.  It's still
used by Debian 9.x, so, we still need to support this.

Unfortunately, we cannot detect if uim actually uses key snooper because it's
switch by build option of uim.  Currently, Debian builds uim as using key
snooper.  So, we should assume uim uses key snooper always.  On the other
hand, somebody *might* use uim built as not using key snooper, so, let's
decide if uim uses key snooper with new pref,
"intl.ime.hack.uim.using_key_snooper", but its default should be true.

Note that ibus and Fcitx also have the mode to use key snooper (perhaps for
backward compatibility with uim).  However, it's not enabled in default
settings and even if it's enabled, Firefox is in whitelist in the default
settings of them for stop using key snooper.  Therefore, we don't need to
support key snooper mode for them unless we'll get some requests to
support their key snooping mode.

Review commit: https://reviewboard.mozilla.org/r/227014/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/227014/

Comment 3

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

FYI: As far as I tested, scim doesn't use key snooper on Debian. So, without any hack, I see keydown and keyup events as expected.

Comment 4

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

Comment on attachment 8958066 [details]
Bug 1444572 - IMContextWrapper should dispatch fake eKeyDown event during composition if active IM is uim

Review request updated; see interdiff: https://reviewboard.mozilla.org/r/227014/diff/1-2/

Comment 5

[Makoto Kato [:m_kato]]

Comment on attachment 8958066 [details]
Bug 1444572 - IMContextWrapper should dispatch fake eKeyDown event during composition if active IM is uim

https://reviewboard.mozilla.org/r/227014/#review233368

Comment 6

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/e226de7caa88
IMContextWrapper should dispatch fake eKeyDown event during composition if active IM is uim r=m_kato

Comment 7

[Dorel Luca [:dluca]]

Backed out changeset e226de7caa88 (bug 1444572) for conflicts while backing out 1443421

https://hg.mozilla.org/integration/autoland/rev/3c176f583fe86a705f54053f9a6b6e161fb91734

Comment 8

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/b1826c93ea23
IMContextWrapper should dispatch fake eKeyDown event during composition if active IM is uim r=m_kato

Comment 9

[Stefan Hindli [:stefan_hindli]]

https://hg.mozilla.org/mozilla-central/rev/b1826c93ea23