LocaleManager for handling android language switch at runtime

LocaleManager.java

public class LocaleManager {
    private static final String LANGUAGE_KEY       = "CHOOSE_LANGUAGE";

    public static Context setLocale(Context c) {
        String savedLanguage = getLanguage(c);
        return savedLanguage == null ? c : updateResources(c, savedLanguage);
    }

    public static Context setNewLocale(Context c, String language) {
        persistLanguage(c, language);
        return updateResources(c, language);
    }

    public static Context setNewLocale(Context c, Locale newLocale) {
        persistLanguage(c, newLocale.toString());
        return updateResources(c, newLocale);
    }

    public static String getLanguage(Context c) {
        SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(c);
        Locale currentLocale = getLocale(c.getResources());
        return !prefs.contains(LANGUAGE_KEY) ? null : prefs.getString(LANGUAGE_KEY, currentLocale.toString());
    }

    @SuppressLint("ApplySharedPref")
    private static void persistLanguage(Context c, String language) {
        SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(c);
        // use commit() instead of apply(), because sometimes we kill the application process immediately
        // which will prevent apply() to finish
        prefs.edit().putString(LANGUAGE_KEY, language).commit();
    }

    private static Context updateResources(Context context, String language) {
        Locale locale = new Locale(language);
        Locale.setDefault(locale);
        return updateResources(context, locale);
    }

    private static Context updateResources(Context context, Locale locale) {
        Resources res = context.getResources();
        Configuration config = new Configuration(res.getConfiguration());
        if (Build.VERSION.SDK_INT >= 17) {
            config.setLocale(locale);
            context = context.createConfigurationContext(config);
            // I need to set this so that recall setText(R.string.xxxx) works
            res.updateConfiguration(config, res.getDisplayMetrics());
        } else {
            config.locale = locale;
            res.updateConfiguration(config, res.getDisplayMetrics());
        }
        return context;
    }

    public static Locale getLocale(Resources res) {
        Configuration config = res.getConfiguration();
        return Build.VERSION.SDK_INT >= 24 ? config.getLocales().get(0) : config.locale;
    }

    public static Locale getSavedLocale(Context c){
        String savedLanguage = getLanguage(c);
        return savedLanguage == null ? getLocale(c.getResources()) : new Locale(getLanguage(c));
    }
}

Hello. Thank you for this work. I have converted it to Kotlin : https://github.com/reuniware/Kotlin-LocaleManager/blob/master/LocaleManager.kt