After the screen rotation, the language of my application will be changed

Question

I have created a bilingual (having two languages) android application. I have inserted my resource strings in two files:

For Persian language (default)
values/st         


        

Answer 1

You can create custom ContextWrapper

public class mContextWrapper extends ContextWrapper {
    public mContextWrapper(Context base){
        super(base);
    }

    @SuppressWarnings("deprecation")
    public static ContextWrapper wrap(Context context, String language) {
        Configuration config = context.getResources().getConfiguration();
        Locale sysLocale = null;
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
            sysLocale = getSystemLocale(config);
        } else {
            sysLocale = getSystemLocaleLegacy(config);
        }
        if (!language.equals("") && !sysLocale.getLanguage().equals(language)) {
            Locale locale = new Locale(language);
            Locale.setDefault(locale);
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
                setSystemLocale(config, locale);
            } else {
                setSystemLocaleLegacy(config, locale);
            }
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR1) {
                context = context.createConfigurationContext(config);
            } else {
                context.getResources().updateConfiguration(config, context.getResources().getDisplayMetrics());
            }
        }
        return new mContextWrapper(context);
    }

    @SuppressWarnings("deprecation")
    public static Locale getSystemLocaleLegacy(Configuration config){
        return config.locale;
    }

    @TargetApi(Build.VERSION_CODES.N)
    public static Locale getSystemLocale(Configuration config){
        return config.getLocales().get(0);
    }

    @SuppressWarnings("deprecation")
    public static void setSystemLocaleLegacy(Configuration config, Locale locale){
        config.locale = locale;
    }

    @TargetApi(Build.VERSION_CODES.N)
    public static void setSystemLocale(Configuration config, Locale locale){
        config.setLocale(locale);
    }
}

and in your activity attachBaseContext attach your custom ContextWrapper

 @Override
    protected void attachBaseContext(Context newBase) {
        globalClass = (YouAppClass)newBase.getApplicationContext();
        //try geting the lang you have setted inside your YouAppClass class
        // or you can use shared preferences for it 
        //pref = PreferenceManager.getDefaultSharedPreferences(newBase)
        lang=globalClass .getLang();
        super.attachBaseContext(mContextWrapper.wrap(newBase,lang));
    }