screens are not navigating in react native - react-native

Question

I have a login screen then from there I navigate to home screen, and on home screen there are 4 buttons Alphabets, Ch-1,Ch-2 and Ch-3, by pressing each of those buttons, I can easily navigate to correct screens but Inside Alphabet screen, I have 2 more buttons Learn and Give test But when I press those, nothing happens , i can't navigate to the respective screens plus there are no errors. I guess its nested navigation.
I might sound stupid to an expert out there :) but I am new (from scratch) to react native and navigation stuff i really have no idea what to do! Will be really thankful if someone helps!
CODE IS GIVEN BELOW:
This is my home.js (its in folder screens):
import React from "react";
import {View, StyleSheet, Text} from 'react-native';
import { TouchableOpacity } from "react-native-gesture-handler";
import { Auth } from "../services";
export default home =({navigation}) => {
return (
<View style={styles.body}>
<Text style={styles.toptext}>
Merheba!
</Text>
<TouchableOpacity onPress={() => navigation.navigate('alphabets')}
style={styles.button}
>
<Text style={styles.buttontext}>Alphabets</Text>
</TouchableOpacity>
<TouchableOpacity onPress={() => navigation.navigate('ch1')}
style={styles.button}
>
<Text style={styles.buttontext}>Chapter 1</Text>
</TouchableOpacity>
<TouchableOpacity onPress={() => navigation.navigate('ch2')}
style={styles.button}
>
<Text style={styles.buttontext}>Chapter 2</Text>
</TouchableOpacity>
<TouchableOpacity onPress={() => navigation.navigate('ch3')}
style={styles.button}
>
<Text style={styles.buttontext}>Chapter 3</Text>
</TouchableOpacity>
<TouchableOpacity onPress={() => Auth.signOut()}
style={styles.button}
>
<Text style={styles.buttontext}>Sign Out</Text>
</TouchableOpacity>
</View>
)
}
This is index.js from screens folder:
export {default as home} from './home';
export {default as login} from './login';
export {default as forgotp} from './login';
export {default as signup} from './signup';
export {default as alphabets} from './alphabets';
export {default as alphl} from './alphl';
export {default as alpht} from './alpht';
export {default as ch1} from './ch1';
export {default as ch2} from './ch2';
export {default as ch3} from './ch3';
This is alphabets.js from screens folder:
import { NavigationContainer } from "#react-navigation/native";
import React from "react";
import {View, StyleSheet, Text} from 'react-native';
import { TouchableOpacity } from "react-native-gesture-handler";
export default alphabets =({navigation}) => {
return (
<View style={styles.body}>
<Text style={styles.toptext}>
Merheba!
</Text>
<TouchableOpacity onPress={() => navigation.navigate('alphl')}
style={styles.button}
>
<Text style={styles.buttontext}>Learning Sheet</Text>
</TouchableOpacity>
<TouchableOpacity onPress={() => navigation.navigate('alpht')}
style={styles.button}
>
<Text style={styles.buttontext}>Give Test</Text>
</TouchableOpacity>
</View>
)
}
AppNavigation.js from navigation folder:
import React from 'react';
import { createStackNavigator } from '#react-navigation/stack';
import home from '../screens/home';
import alphabets from '../screens/alphabets';
import ch1 from '../screens/ch1';
import ch2 from '../screens/ch2';
import ch3 from '../screens/ch3';
const stack=createStackNavigator();
export default AppNavigator = () => {
return(
<stack.Navigator
screenOptions={{
headerShown: null
}}
>
<stack.Screen name="home" component={home} />
<stack.Screen name="alphabets" component={alphabets} />
<stack.Screen name="ch1" component={ch1}/>
<stack.Screen name="ch2" component={ch2} />
<stack.Screen name="ch3" component={ch3} />
</stack.Navigator>
)
}
AlphNavigator.js from navigation folder:
import React from 'react';
import { createStackNavigator } from '#react-navigation/stack';
import alphl from '../screens/alphl';
import alpht from '../screens/alpht';
const stack=createStackNavigator();
export default AlphNavigator = () => {
return(
<stack.Navigator
screenOptions={{
headerShown: null
}}
>
<stack.Screen name="alphl" component={alphl} />
<stack.Screen name="alpht" component={alpht} />
</stack.Navigator>
)
}
& lastly index.js from navigation folder:
import React, {useState, useEffect} from 'react';
import { NavigationContainer } from '#react-navigation/native';
import AppNavigator from './AppNavigator';
import AuthNavigator from './AuthNavigator';
import auth from '#react-native-firebase/auth';
export default AppContainer = () => {
// Set an initializing state whilst Firebase connects
const [initializing, setInitializing] = useState(true);
const [user, setUser] = useState();
// Handle user state changes
function onAuthStateChanged(user) {
setUser(user);
if (initializing) setInitializing(false);
}
useEffect(() => {
const subscriber = auth().onAuthStateChanged(onAuthStateChanged);
return subscriber; // unsubscribe on unmount
}, []);
if (initializing) return null;
return(
<NavigationContainer>
{user ? <AppNavigator/> : <AuthNavigator/>}
</NavigationContainer>
)
}

Answer 1

You aren't defining your "AlphNavigator" in your "AppNavigator".
You should do this inside your AppNavigator:
export default AppNavigator = () => {
return(
<stack.Navigator
screenOptions={{
headerShown: null
}}
>
<stack.Screen name="home" component={home} />
<stack.Screen name="alphabets" component={alphabets} />
<stack.Screen name="alph" component={ AlphNavigator } /> /*here add your AlpNavigator*/
<stack.Screen name="ch1" component={ch1}/>
<stack.Screen name="ch2" component={ch2} />
<stack.Screen name="ch3" component={ch3} />
</stack.Navigator>
)}
It's normal that you do not have any error in this case, because React Navigation does not mark you as an error if a screen does not exist.
The above could be solved if you were using TypeScript.
So now, in order to access to nested navigation screens you should use:
navigation.navigate('alph', { screen: 'alphl' })
The first parameter is the name of the stack navigation, and the second one is an object with the name of the screen inside to this nested navigation.