Input key press event is fired twice (depending on input method ?)

[Jérémy Munsch]

Hi,

when pasting a hostname into synapse (eg. for ssh plugin) it is being pasted twice like:
clipboard: hostname
synapse: hostnamehostname

when hold shift key and selecting a hostname it opens 2 terminal windows for this host.

is there a configuration option for this or is it a bug?

regards,
nean

EDIT: using GTK_IM_MODULE='' synapse solves the problem as a workaround

[Jérémy Munsch (jeremy-munsch)]

I just noticed that if you start synapse from cli the bug does not occur, howhever if you start using a graphical method your pastes will be doubled

[nean (nean.and.i)]

hmm, I can not confirm that.
If I start it via terminal the same issue occurs.
So whats different to your starting option?

[Jérémy Munsch (jeremy-munsch)]

Yeah right i just noticed i had an alias :
GTK_IM_MODULE='' synapse

This was because i had crash from synapse (it made crash my kde (plasma5.3 desktop).
Seems like it solves more problems.

I did had to use on plasma5.2.

I actually have echo $GTK_IM_MODULE => fcitx

So i check into the code: if you set GTK_IM_MODULE='' => paste is triggered once
in no => paste is triggered twice

[Jérémy Munsch (jeremy-munsch)]

I mean i did not have to use on plasma 5.2, cause synapse made no crash

[Jérémy Munsch (jeremy-munsch)]

Indeed key_press_event function is triggered twice so i do not know where is the bug, but sure there is.

[Jérémy Munsch (jeremy-munsch)]

If anyone is aware on how to debug synapse or vala programs don't hesitate, i'm real stranger to this programming language.

[Jérémy Munsch (jeremy-munsch)]

Well definitly a synapse bug.
    public override bool key_press_event (Gdk.EventKey event)
    {
      message("keypress ");
      // this.controller.key_press_event (event);
      return false;
    }
This is some recursive situation because if you comment the controller method the key press is fired once only.

[Jérémy Munsch (jeremy-munsch)]

I found the cause :

im_context.focus_in ();

On controller.vala line 55 the very specific instruction "im_context.focus_in ();"
 // Input Method Fix
if (this.view is Gtk.Window) //this has to be true, otherwise im_context will not work well
{
  Gtk.Window v = this.view as Gtk.Window;

  message ("Using %s input method.", im_context.get_context_id ());

  v.focus_in_event.connect (() => {
    im_context.reset ();
    im_context.focus_in ();
    return false;
  });

  v.focus_out_event.connect (() => {
    im_context.focus_out ();
    return false;
  });

I'm not sure what this is doing.

[Jérémy Munsch (jeremy-munsch)]

This was introduced in
http://bazaar.launchpad.net/~synapse-core/synapse-project/trunk/revision/437#src/ui/controller.vala

[nean (nean.and.i)]

seems it has something to do with the keyboard input method system which is in unity by default at "ibus"

there is a way to set it to "none" which might have the same effect as to set it via environment variable:
http://askubuntu.com/questions/472562/how-to-change-keyboard-input-method-system-to-none-in-ubuntu-gnome

however, I need to find out more about input method, what it is all about and why it behave strange in synapse,...

[Jérémy Munsch (jeremy-munsch)]

@nean it is a synapse bug actually see above.

if you want to change you input method use : im-config to set it to none.

https://en.wikipedia.org/wiki/Input_method

Like said, event is fired twice because of some code part i have tried to reach to original author but i'm waiting for an answer now.
I guess we could try to remove this code part.
If i have got any answer soon i'll make a merge request to fix this.

[nean (nean.and.i)]

thanks jeremy.

temp. WORKAROUND:
as tested in ubuntu 14.04.x
switching input method to "none" via im-config solves the problem.
(seems to be the same as to switch it via: system settings -> language support -> keyboard input method system )
However this might not be a solution for people who need "input method" set to "ibus" (korean, chinese keyboard etc,...)