App.js

import React, { useState } from 'react';
import { StyleSheet } from 'react-native';
import { createStore, combineReducers, applyMiddleware } from 'redux';
import { Provider } from 'react-redux';
import AppLoading from 'expo-app-loading';
import * as Font from 'expo-font';
import ReduxThunk from 'redux-thunk';

import productReducer from './store/reducers/product';
import cartReducer from './store/reducers/cart';
import ordersReducer from './store/reducers/orders';
import authReducer from './store/reducers/auth';
import NavigationContainer from './navigation/NavigationContainer';

const rootReducer = combineReducers({
  products: productReducer,
  cart: cartReducer,
  orders: ordersReducer,
  auth: authReducer,
});

const store = createStore(rootReducer, applyMiddleware(ReduxThunk));

const fetchFonts = () => {
  return Font.loadAsync({
    'open-sans': require('./assets/fonts/OpenSans-Regular.ttf'),
    'open-sans-bold': require('./assets/fonts/OpenSans-Bold.ttf'),
  });
};

export default function App() {
  const [fontLoaded, setFontLoaded] = useState(false);

  if (!fontLoaded) {
    return (
      <AppLoading
        startAsync={fetchFonts}
        onFinish={() => setFontLoaded(true)}
        onError={console.warn}
      />
    );
  }

  return (
    <Provider store={store}>
      <NavigationContainer />
    </Provider>
  );
}

const styles = StyleSheet.create({});