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

This is all over the place, to put it simply

setprop will only work on an AVD or a rooted physical device

The alternative is to use the settings in the Launcher.

Rooted device or AVD this works:

/platform-tools/adb shell
root@generic:/ # getprop persist.sys.language
getprop persist.sys.language
en
root@generic:/ # setprop persist.sys.language fr
setprop persist.sys.language fr
root@generic:/ # setprop persist.sys.country CA
setprop persist.sys.country CA
root@generic:/ # stop
stop
root@generic:/ # start
start
root@generic:/ # sleep 5
sleep 5
root@generic:/ # getprop |grep lang
getprop |grep lang
[persist.sys.language]: [fr]
root@generic:/ # getprop |grep country
getprop |grep country
[persist.sys.country]: [CA]
root@generic:/ #