undefined is not an object (evaluating 'Context._context') - React Native

Solution 1:

there is some mistake in your code

1. you are not exporting UserContext but you are importing UserContext in App.js file
2. you are trying to use useContext and provider in same file but you have to useContext inside of Provider child component
3. you are non_user_stack with first letter capital but you have to make first letter capital

UserContext.js : you have to export UserContext in this file

import React, { useState, useEffect } from "react";
import { Text } from 'react-native'
import * as Permissions from "expo-permissions";
import axios from "axios";
import { AsyncStorage } from "react-native";
//import registerForPushNotificationsAsync from "../Hooks/registerForPushNotifications";
import Constants from "expo-constants";

const UserContext = React.createContext();
export default UserContext;
const IS_SIGNEDIN = "is_signed_in";

export const UserProvider = ({ children }) => {
  const [isSignedIn, setSignIn] = useState(null);
  const [didAuthenticate, setAuthenticated] = useState(null);
  const check_and_set_signin_status = async () => {
    const signed_in = await AsyncStorage.getItem(IS_SIGNEDIN);

    if (signed_in == null || signed_in == "false") {
      await AsyncStorage.setItem(IS_SIGNEDIN, "false");
      setSignIn("false");
    } else {
      setSignIn("true");
    }

  };


  return (
    <UserContext.Provider
      value={{
        isSignedIn, // well use this for conditional rendering

        check_and_set_signin_status,
      }}
    >
      {children}
    </UserContext.Provider>
  );
};

App.js Code :

const App = () => {
 const { isSignedIn, check_and_set_signin_status } = useContext(UserContext); //<-- causes crash
  console.log( isSignedIn, check_and_set_signin_status ,"useContext")
  return isSignedIn === "false" ? (
    <UserMenu />
  ) : (
    <Non_user_stack></Non_user_stack>
  );
};

const jsx = () => (
  <UserProvider>
    <App />
  </UserProvider>
);

export default jsx;

Solution 2:

In my case I imported badly

import ThemeContext from '../contexts/theme-context';

Instead

import { ThemeContext } from '../contexts/theme-context';

Solution 3:

You should always check what you're exporting from your context folder

In my case I import { LocalContext } from ".././services/location/location.context";

instead of import { LocationContext } from ".././services/location/location.context";