Change Device language via ADB

Question

I want to change language via ADB. I try:

adb shell setprop persist.sys.language fr;setprop persist.sys.country CA;stop;sleep 5;start

but I

Answer 1

Try this

adb shell "su -c 'setprop persist.sys.language fr; setprop persist.sys.country CA; stop; sleep 5; start'

You need a rooted device.