How to change Locale? Not working on some Devices

Question

I'm writing app that support two language and I'm changing language with Change app Locale here my code :

 Locale locale = new Locale("fa");
            Locale.setDefault(locale);
            Configuration configs = new Configuration();
            configs.locale = locale;
            getBaseContext().getResources().updateConfiguration(configs, getBaseContext().getResources().getDisplayMetrics());

And

in manifest I'm set android:supportsRtl="true"

These codes working in many Devices but in some devices not working . for example Texts not Translating but Direction change .

Tested Devices :

• Samsung J5Pro 2018 (android = 7.1): Worked
• Pixel 2 API 26 : Worked
• Samsung J7 2017 (android = 7): Worked
• Nexus 5 (android = 6) : Not Worked
• Samsung Galaxy G531 (android < lollipop) : Not Worked

Answer 1

i have found my solution , my problem was i'm inserted "fa" in Locale and my String Values Directory name was values-fa-rlIR, so names are different so not worked ,i'm wondering why it's working on some devices!

I'm just change the String Values Directory name from values-fa-rlIR to values-fa and it's working well.