I want to change the language of the app and this works fine until API 26.
For api > 25 I put Locale.setDefault(Locale.Category.DISPLAY, mynewlanglocale);
After use all solution in all sources finally i found my issue. That makes me angry for 2 days.
Everyone knows that in Android Oreo (API 26) we must use createConfigurationContext, But My problem is using Country name with local.
Replace
en_US with en
ar_AE with ar
fa_IR with fa
And my problem solved.
Hope to help someone