将Redux工具包实现到认证后Hook报错

Question

I keep getting an error when I run my app, and the screen is just white.

 ERROR  Error: Invalid hook call. Hooks can only be called inside of the body of a function component. This could happen for one of the following reasons:
1. You might have mismatching versions of React and the renderer (such as React DOM)       
2. You might be breaking the Rules of Hooks
3. You might have more than one copy of React in the same app
See https://reactjs.org/link/invalid-hook-call for tips about how to debug and fix this problem., js engine: hermes
 ERROR  Invariant Violation: Module AppRegistry is not a registered callable module (calling runApplication). A frequent cause of the error is that the application entry file path is incorrect.
      This can also happen when the JS bundle is corrupt or there is an early initialization error when loading React Native., js engine: hermes
 ERROR  Invariant Violation: Module AppRegistry is not a registered callable module (calling runApplication). A frequent cause of the error is that the application entry file path is incorrect.
      This can also happen when the JS bundle is corrupt or there is an early initialization error when loading React Native., js engine: hermes

Full code is available on my GitHub, but let I'll past the areas of the code I was fiddling with: https://github.com/astuertz/hashtagValues/commits/master

First, here's my store.js:

import { configureStore } from '@reduxjs/toolkit';
import activeImgReducer from '../features/counter/activeImgSlice';
import userAuthReducer from '../features/counter/userAuthSlice';

export default configureStore({
  reducer: {
    activeImg: activeImgReducer,
    user: userAuthReducer
  }
})

Here's my index.js:

/**
 * @format
 */

import React from 'react';
import {AppRegistry} from 'react-native';
import App from './App';
import {name as appName} from './app.json';
import store from './src/app/store';
import { Provider } from 'react-redux';

const reduxApp = () => (
    <Provider store={store}>
        <App />
    </Provider>
  );

AppRegistry.registerComponent(appName, () => reduxApp);

And my App.js (without styles):

import React from 'react';
import {View, Text, StyleSheet} from 'react-native';
import Navigation from './src/components/routes/navigation';
import Amplify from 'aws-amplify';
import config from './src/aws-exports';
import { withAuthenticator } from 'aws-amplify-react-native';

Amplify.configure({
  ...config,
  Analytics: {
    disabled: true,
  },
});

const App = () => {

  return (
    <View style={styles.root}>
      <Navigation />
    </View>
  );
};

Here's my navigation.js (everything from the root stack down--the root stack has several other stacks nested in it):

const RootStack = createNativeStackNavigator();
const RootStackScreen = () => {

    const [isLoading, setIsLoading] = useState(true);
    const [user, setUser] = useState(null);

    useEffect(() => {
        setTimeout(() => {
            setIsLoading(!isLoading);
            setUser('user');
        }, 2500)
    }, []);

    return (

    <RootStack.Navigator screenOptions={{ 
        animationEnabled: false, 
        headerShown: false, 
        presentation: 'modal',
        }}>
        {isLoading ? (
        <RootStack.Screen name="LoadingScreen" component={LoadingScreen} /> 
        ) : user ? (
        <RootStack.Screen name="AppTabs" component={AppTabsScreen} /> 
        ) : (
        <RootStack.Screen name="AuthStackScreen" component={AuthStackScreen} />
        )}
        <RootStack.Screen name="Gallery" component={GalleryScreen} options={{ 
          animationEnabled: true, 
          cardStyle: { 
            backgroundColor: 'black', 
          }, 
        }}/>
    </RootStack.Navigator>
    );
};

export default () => {

  return (
  <NavigationContainer>
      <RootStackScreen />
  </NavigationContainer>
  );
};

I now have it back to the way I had it before the error started occurring.

The only other thing I was messing with is the Sign In Screen and the Profile Screen (with Sign Out). Here's the Sign In Screen:

import React, {useState} from 'react';
import { 
  View, 
  Text, 
  StyleSheet, 
  Image, 
  Dimensions, 
  TextInput, 
  Button, 
  TouchableWithoutFeedback,
  Keyboard,
  TouchableOpacity,
  Alert,
} from 'react-native';
import logo from '../../graphics/Values_logo.png';
import { useNavigation } from '@react-navigation/native';
import { Auth } from 'aws-amplify';
import { useSelector, useDispatch, } from 'react-redux';
import { validateUser } from '../../features/counter/userAuthSlice';

const WIDTH = Dimensions.get("window").width;
const HEIGHT = Dimensions.get("window").height;

const SignIn = () => {

  const navigation = useNavigation();
  const dispatch = useDispatch();

  const [email, setEmail] = useState('');
  const [password, setPassword] = useState('');

  const onPressSignIn = async () => {
    if (email.length < 1 || password.length < 1) return Alert.alert('no input', 'please input an email and password to log in.');
    try {
      const u = await Auth.signIn(email, password);
      dispatch(validateUser(u));
    } catch(e) {
      Alert.alert('Login Failed!', e.message);
      return;
    }
    Alert.alert('Login Successful!');
    return;
  }

  const renderLogo = (
    <Image 
    source={logo}
    style={styles.logoSize}  
    resizeMode='contain' 
  />
  );

  const inputElements = (
    <>
    <TextInput 
      placeholder='email'
      value={email}
      onChangeText={setEmail}
      style={styles.textInput} 
    />
    <TextInput 
      placeholder='password'
      value={password}
      onChangeText={setPassword}
      style={styles.textInput}
      secureTextEntry={true} 
    />
    <TouchableOpacity
      onPress={onPressSignIn}  
      style={styles.button} 
    >
      <Text style={styles.buttonText}>Sign In</Text>
    </TouchableOpacity>
    <Text 
      style={styles.hyperlink} 
    >Forgot Password?</Text>
    <Text 
      style={styles.hyperlink} 
      onPress={() => navigation.push("SignUp")} 
    >Sign Up</Text>
    </>
  );

  return (

    <TouchableWithoutFeedback 
      onPress={() => Keyboard.dismiss()}>
      <View style={styles.pageContainer}>
        <View style={styles.logo}>
          {renderLogo}
        </View>
        <View style={styles.inputContainer} >
          {inputElements}
        </View>     
      </View>
    </TouchableWithoutFeedback>
  );
}

And the Profile Screen:

import React from 'react';
import {View, Text, StyleSheet, Button, Alert,} from 'react-native';
import { SafeAreaView } from 'react-native-safe-area-context';
import { Auth } from 'aws-amplify';
import { useSelector, useDispatch, } from 'react-redux';
import { signOutUser } from '../../features/counter/userAuthSlice';

const dispatch = useDispatch();

const onSignOut = async () => {
  try {
      await Auth.signOut();
      dispatch(signOutUser());
  } catch (error) {
      Alert.alert('error signing out: ', error.message);
      return;
  }
  Alert.alert('Sign Out Successful!');
}

const ProfileScreen = () => {

  return (
      <SafeAreaView style={styles.pageContainer}>
        <Text>ProfileScreen</Text>
        <Button title="Sign Out" onPress={onSignOut} />
      </SafeAreaView>
  );
};

const styles = StyleSheet.create({
  root: {
    flex: 1
  },
  pageContainer: {
    justifyContent: 'center',
    alignItems: 'center',
    flex: 1,
    width: '100%'
  }
});


export default ProfileScreen;

I'm really not sure what I did to break my app or how to fix it.

Answer 1

In Profile Screen, you are calling const dispatch = useDispatch(); which is outside of the component and is an invalid call. It has to be called in inside ProfileScreen. When you are not sure where the problem occurs try commenting you code and see if it works without them. Like commenting your screens one by one would help you find which screen the error is caused in etc.