Set initial route conditionally in react native

Issue

I'm building a mobile app in React Native of which auth process is like Whatsapp.I want to set the initialRoute to 'Signup' if there is no token in AsyncStorage and dashboard if token is present.I tried this with the following code, but it always points me to dashboard even though there is no token in AsyncStorage.

Drawer

import { AsyncStorage } from 'react-native'
import Signup from '../screens/SignupScreen'
import CustomDrawer from './CustomDrawer'

const DrawNavigator = createDrawerNavigator({
  Dashboard: { screen: Home },
  Signup: { screen: Signup},
  },{
  initialRouteName: AsyncStorage.getItem('token') ? 'Dashboard' : 'Signup',
contentComponent: CustomDrawer,
drawerOpenRoute: 'drawerOpen',
drawerCloseRoute: 'drawerClose',
drawerToggleRoute: 'drawerToggle'});

export default DrawNavigator;

EDIT

async function checkToken(){
  var token = await AsyncStorage.getItem('token')
  return token ? true : false
}

initialRouteName: checkToken()  ? 'Dashboard' : 'Signup',

But the app stills gives access to Dashboard even it there is no token stored

Solution

AsyncStorage works asynchronously, therefore the expression that is interpreted in your condition is the resulting Promise object from the getItem function.

You could try to use the await statement to block the execution until you know if there is a token. This is not reccomended because you'll be blocking the initialisation of your app.

You can also try to have a default route that will check for a token in the componentDidMount and then redirect based on the result.

Side note: AsyncStorage imported from "react-native" is now deprecated and will be removed in a future release of React-Native. Consider installing "@react-native-community/async-storage" instead.

Answered By - RDardelet