androidonresumerecreate

Refresh(recreate) the activities in back stack when change locale at run time


I have an Activity say ActivityMain from this activity I moved to another activity called ActivitySettings and in settings activity I'm changing the App locale by clicking on a button, and using recreate I achieved the change I need in current activity but when I press back my `ActivityMain' will resume but locale is not updated.

Can some one tell me how to 'Recreate' backstack activities? what will be the correct approach.

I can't call recreate on refresh as it will be infinite loop


Solution

  • In each Activity's onCreate() you can maintain the currentLangCode. Check this value in onResume(), if it differs, you can conclude the locale was change and recreate()

    You can do it as follows:

    public class ActivityA extends AppCompatActivity{
        private String currentLangCode;
         @Override
        protected void onCreate(Bundle savedInstanceState) {
            ...
            currentLangCode = getResources().getConfiguration().locale.getLanguage();
            ...
        }
        @Override
        public void onResume(){
            ...
            if(!currentLangCode.equals(getResources().getConfiguration().locale.getLanguage())){
                currentLangCode = getResources().getConfiguration().locale.getLanguage();
                recreate();
            }
        }
        ...
    }
    

    My Recommendation

    If you want to apply it for all the Activities, then simply create BaseActivity as follows:

    public class BaseActivity extends AppCompatActivity{
        private String currentLangCode;
         @Override
        protected void onCreate(Bundle savedInstanceState) {
            ...
            currentLangCode = getResources().getConfiguration().locale.getLanguage();
            ...
        }
        @Override
        public void onResume(){
            ...
            if(!currentLangCode.equals(getResources().getConfiguration().locale.getLanguage();)){
                currentLangCode = getResources().getConfiguration().locale.getLanguage();
                recreate();
            }
        }
        ...
    }
    

    Extend all Activities from BaseActivity

    public class ActivityA extends BaseActivity{
    
         @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            ...
        }
        @Override
        public void onResume(){
          super.onResume();
        }
        ...
    }