App.js

import React from 'react'
import { AsyncStorage } from 'react-native';
import { ApolloProvider, createNetworkInterface, ApolloClient } from 'react-apollo'
import Mainuser from './components/mainuser'
import Login from './components/Login'
import Register from './components/Register'

const networkInterface = createNetworkInterface({ uri: 'http://192.168.1.3:4000/graphql'
 })

getUserId = async () => {

  try {
      const value = await AsyncStorage.getItem('user-token');
      if (value !== null){    
        return value
      }
    } catch (error) {
      console.log(error)     
    }
    return null
}

networkInterface.use([{
  applyMiddleware(req, next) {
    if (!req.options.headers) {
      req.options.headers = {}
    }
    const jwt = getUserId()
    //if(jwt){
      Promise.resolve(jwt).then(function(token) {

        if(token) req.options.headers.authorization = `Bearer ${token}`
        next()
      })
    //}
  }
}])

const client = new ApolloClient({ networkInterface })

export default (
  <ApolloProvider client={client}>
    <Createuser />
  </ApolloProvider>
)