I18Next - wait for Redux store to be set with local data

Question

I would like for i18next to wait for the redux store to be ready. I'm storing the user's chosen language in the store, using persistor from redux-persist to rehydrate it at app startup. I tried to set the language from the store :

// ...
import store from '../redux';
// ...
const lng = store.getState().user.language
  ? store.getState().user.language
  : Localization.locale.slice(0, 2);

i18next
  // .use(languageDetector)
  .use(initReactI18next)
  .init({
    fallbackLng: 'en',
    debug: true,
    resources,
    lng,
  });

But at this point the store is still in its initialState and not rehydrated yet. Is there a way I could do this?

Answer 1

So the PersistGate can implement an onBeforeLift method, waiting for it to be resolved before lifting the "loading" state.

const onBeforeLift = async () => {
  await initI18Next();
};

export default function App(): React.ReactElement {
  return (
    <Provider store={store}>
      <PersistGate
        loading={<SplashScreen />}
        persistor={persistor}
        onBeforeLift={onBeforeLift}
      >
        <StatusBar hidden />
        <MainNavigation />
      </PersistGate>
    </Provider>
  );
}

And in i18n.ts:

const resources = {
  en: { translation: en },
  fr: { translation: fr },
  he: { translation: he },
};

export const init = () => {
  const lng = store.getState().user.language
    ? store.getState().user.language
    : Localization.locale.slice(0, 2);

  return (
    i18next
      .use(initReactI18next)
      .init({
        fallbackLng: 'en',
        debug: true,
        resources,
        lng,
      })
  );
};

export default i18next;