Can't execute bash script from shortcut

I try to execute a bash script from a shortcut set from the settings (system settings > keyboard > shortcuts or analogous), but it doesn't execute, although it works just fine from the terminal...

The script is as following :

#!/bin/bash
#"$1" should be a number from 0 to 5
if [ "$#" == 0 ]; then
   echo "Ce programme nécessite en argument le nombre d'étoiles (de 0 à 5) à attribuer à la chanson qui est en train de tourner dans Rhythmbox."
   exit
fi

rhythmbox-client --set-rating $1
notify-send "$1 étoiles" "$(rhythmbox-client --print-playing)" --expire-time=1000 --icon=starred

Then I set the shortcut, but it doesn't work (Noting happens). As said before, the same code executed from the terminal works great...

Thanks for helping me !!