How do I run a script when I switch between keyboard layouts

Question

I use more than one keyboard layout, and I would like to find a way to run a script when I switch between them.

Is this possible?

So far, I can assign a shortcut for a script like this:

#!/bin/bash

#switch between two layouts (English and Greek in this case)
current_layouts=$(gsettings get org.gnome.libgnomekbd.keyboard layouts)

if [ "$current_layouts" = "us" ]; then
    gsettings set org.gnome.libgnomekbd.keyboard layouts "['gr']"
else 
    gsettings set org.gnome.libgnomekbd.keyboard layouts "['us']"
fi

exec /path/to/another/script

But using this method, I can use only that shortcut to switch between layouts and the keyboard indicator will disappear from the status menu, what is unpleasantly.

Answer 1

dconf watch can be used as an event receiver, example (in Ubuntu 13.10/14.04):

dconf watch /org/gnome/desktop/input-sources/current | xargs -L 2 sh -c "echo kbd layout changed" &

Answer 2

I would do it the other way around, run a script that changes the layout. That way you can do anything else you want with the same script. Unfortunately, it is quite hard to find out you current keyboard layout. I have found no approach that works for all methods of layout switching. For some reason, there is a difference if you switch with setxkbmap or via the GUI shortcuts.

So, my workaround is to always switch using setxkbmap. I have a script that calls setxkbmap and I have bound that script to a shortcut in my desktop environment so that I can switch easily. The example below is for Greek, and US layouts, you will have to modify it to fit your setup:

#!/usr/bin/env bash
key=`xmodmap -pke | grep -w "59" | awk '{print \$NF}'` 
## If this is the "us" layout, that will return "less"
if [ $key == "less" ]; then
    setxkbmap gr
    ## Add other things to be done here
else
    setxkbmap us
    ## Add other things to be done here
fi

Answer 3

gsettings monitor org.gnome.desktop.input-sources mru-sources \
        | xargs -L1 bash -c 'source /path/to/your/script.sh'