ibus-daemon: make sure to focus out engine when unset.

ibus-daemon: make sure to focus out engine when unset.


BUG=none
TEST=manual

[Daiki Ueno, 2012-03-14 07:08:50]

I often got a problem that IME menus are not shown (I can provide a screenshot
if necessary).  After some debugging, it seems that properties sent from engine
are overwritten with an empty prop list.  The timeline I observed is:

1. engine emits "RegisterProperties"
2. context obtains focus
3. ibus-daemon emits empty "RegisterProperties" via:
 bus_ibus_impl_set_focused_context (ibusimpl.c:521)
 bus_input_context_unset_engine (inputcontext.c:2009)
4. engine does not emit "RegisterProperties" again, because engine's "FocusIn"
is not called since context (and engine) has already focus (i.e.
context->has_focus == engine->has_focus == TRUE)

This patch is to mark engine->has_focus = FALSE, in
bus_input_context_unset_engine.

[Daiki Ueno, 2012-03-15 02:35:21]

On 2012/03/14 07:08:50, Daiki Ueno wrote:
> I often got a problem that IME menus are not shown (I can provide a screenshot
> if necessary).

FWIW, here they are.

normal case:
http://ueno.fedorapeople.org/ibus-gtk3/menu.png

failure case:
http://ueno.fedorapeople.org/ibus-gtk3/no-menu.png

Additional note:
after 3, bus_ibus_impl_set_focused_context calls bus_input_context_enable and it
calls bus_engine_proxy_focus_in.  However, at that time engine already has
focus, so:

  1112  void
  1113  bus_engine_proxy_focus_in (BusEngineProxy *engine)
  1114  {
  1115      g_assert (BUS_IS_ENGINE_PROXY (engine));
  1116      if (!engine->has_focus) {
  1117          engine->has_focus = TRUE;
  1118          g_dbus_proxy_call ((GDBusProxy *)engine,
  1119                             "FocusIn",

"FocusIn" D-Bus call is not sent.

[Peng, 2012-03-15 04:02:03]

lgtm

[Daiki Ueno, 2012-03-15 05:13:33]

Hmm, though I'm going to push this (with slight modification to the comment)
soon, perhaps this change is not perfect.

When I focus in to non IM aware clients (like xterm started with "XMODIFIER=
xterm"), the IME menu disappears (and appears when I switch back to IM aware
clients).  That's harmless but looks unnatural than showing "No input window" as
previous versions.  It might be good to track properties sent from engine when
global engine is enabled.