Keyboard layout indicator for i3 with i3status

I am using i3 window manager with i3status bar. This post describes how to set up a responsive keyboard layout indicator if you are using multiple keyboard layouts. It looks like this:

In the screenshot above it shows that I have 2 keyboard layouts: American English (us) and Ukrainian (ua) and currently the first one is active.

Display part is implemented by this script. It depends on xkblayout-state utility. Save this script and compiled version of xkblayout-state to your ~/bin/ directory.

In your ~/.config/i3status/config add "output_format = i3bar" line to general section:

general {

        colors = true

        interval = 5

        output_format = i3bar        

}

In ~/.config/i3/config add:

bar {

    status_command ~/bin/i3status.sh

    output primary

    tray_output primary

}

and

exec_always "setxkbmap -layout us,ua -option 'grp:alt_space_toggle'"

This will allow you to switch keyboard with Alt+SPACE, and the indicator will display the current status.

So far, so good, but the problem is that the status bar is updated every 5 seconds. We would want keyboard layout indicator to update immediately. This could be done. It will require another command line utility: xkb-switch (available via apt on Ubuntu Linux). The idea is to implement switching via i3 hotkey, which will also trigger an instant status bar update. Here is  a section of i3 config:

exec_always "setxkbmap -layout us,ua"

bindsym Mod1+space exec "xkb-switch -n; pkill -x --signal=SIGUSR1 i3status"

We removed ALT+SPACE toggle option from setxkbmap, and implemented it as bindsym. Sending USR1 signal to i3status triggers the immediate update.