Develop Reference

undefined is not an object (evaluating 'navigation.navigate') when trying to navigate to a file that will open camera on the phone

I'm trying to navigate to my page "CameraPage.js" but I'm getting this error "undefined is not an object (evaluating 'navigation.navigate')". Can anybody see the problem? This ismy first question here so please tell me if I can be more specific.
Here's my App.js:
import { StyleSheet, Text, View, TouchableOpacity, Pressable } from 'react-native';
import React, {useEffect, useState} from "react";
import { FontAwesome } from '#expo/vector-icons';
import { useNavigation } from '#react-navigation/native';
export default function App({ navigation }) {
return (
<View style={styles.container}>
<View style={styles.buttonContainer}>
<TouchableOpacity onPress ={() => navigation.navigate('CameraFunction')}>
<FontAwesome name="camera" size={100} color="#FFB6C1" />
</TouchableOpacity>
<Pressable>
<FontAwesome name="photo" size={100} color="#FFB6C1" />
</Pressable>
</View>
</View>
);
}
const styles = StyleSheet.create({
container: {
flex: 1,
justifyContent: 'center',
alignItems: 'center',
backgroundColor: '#FFDBE9'
},
buttonContainer: {
backgroundColor: 'transparent',
justifyContent: 'space-between',
},
});
Here is my CameraPage.js file:
import {StyleSheet, Text, View, TouchableOpacity} from 'react-native';
import {Camera, CameraType} from 'expo-camera';
import {useEffect, useState} from "react";
export default function CameraPage() {
const [hasPermission, setHasPermission] = useState(null);
const [type, setType] = useState(CameraType.back);
useEffect(() => {
(async () => {
const {status} = await Camera.requestCameraPermissionsAsync();
setHasPermission(status === 'granted');
})();
}, []);
if (hasPermission === null) {
return <View/>;
}
if (hasPermission === false) {
return <Text>No access to camera</Text>;
}
return (
<View style={styles.container}>
<Camera style={styles.camera} type={type}>
<View style={styles.buttonContainer}>
<TouchableOpacity
style={styles.button}
onPress={() => {
setType(type === CameraType.back ? CameraType.front : CameraType.back);
}}>
<Text style={styles.text}> Flip </Text>
</TouchableOpacity>
</View>
</Camera>
</View>
);
}
const styles = StyleSheet.create({
container: {
flex: 1,
},
camera: {
flex: 1,
},
buttonContainer: {
flex: 1,
backgroundColor: 'transparent',
flexDirection: 'row',
margin: 20,
},
button: {
flex: 0.1,
alignSelf: 'flex-end',
alignItems: 'center',
},
text: {
fontSize: 18,
color: 'white',
},
});
Here is my navigation file:
import React from 'react';
import {createStackNavigator} from '#react-navigation/stack';
import {NavigationContainer} from '#react-navigation/native';
import CameraPage from "../Camera/CameraPage";
const Routes = createStackNavigator();
export default function Navigator() {
return (
<NavigationContainer>
<Routes.Navigator>
<Routes.Screen
name="CameraFunction"
component={CameraPage}
/>
</Routes.Navigator>
</NavigationContainer>
);
}

Your navigation container must be wrapped around the root of your application or otherwise the navigation object will not be passed to the components that you have defined as screens.
The following fixes your issue.
export default const App = () => {
return (
<NavigationContainer>
<Routes.Navigator>
<Routes.Screen name="Home" component={HomeScreen} />
<Routes.Screen
name="CameraFunction"
component={CameraPage}
/>
</Routes.Navigator>
</NavigationContainer>
);
}
Your HomeScreen contains the old code from App, but now you can access the navigation object since we have defined HomeScreen as a screen inside the navigator. It will be passed to that screen by the navigation framework. Notice as well that HomeScreen is the initial screen of your application.
export default function HomeScreen({ navigation }) {
return (
<View style={styles.container}>
<View style={styles.buttonContainer}>
<TouchableOpacity onPress ={() => navigation.navigate('CameraFunction')}>
<FontAwesome name="camera" size={100} color="#FFB6C1" />
</TouchableOpacity>
<Pressable>
<FontAwesome name="photo" size={100} color="#FFB6C1" />
</Pressable>
</View>
</View>
);
}
const styles = StyleSheet.create({
container: {
flex: 1,
justifyContent: 'center',
alignItems: 'center',
backgroundColor: '#FFDBE9'
},
buttonContainer: {
backgroundColor: 'transparent',
justifyContent: 'space-between',
},
});
Notice, that you need to navigate back to the HomeScreen once you have navigated to the CameraPage. You can use the navigation object in the CameraPage as well and trigger navigation.goBack to achieve this effect.

You just use #react-navigation/native-stack in place of #react-navigation/stack in App.js file then it will working perfect ,
import * as React from 'react';
import {NavigationContainer} from '#react-navigation/native';
import {createNativeStackNavigator} from '#react-navigation/native-stack';
import Home from './TopTabBar/Home';
import 'react-native-gesture-handler';
const Stack = createNativeStackNavigator();
function App() {
return (
<NavigationContainer>
<Stack.Navigator>
<Stack.Screen name="Home" component={Home} />
</Stack.Navigator>
</NavigationContainer>
);
}
export default App;

Navigation, not working from Pulled functions

I will try to explain this as best I can, I'm still new and have a hard time understanding the terminology.
I am working on a react native project. I have created two files. One Header.js and one footer.js.
I have successfully pulled them in to my Home Screen. However the buttons, inside footer.js, no longer fires. I get; undefined is not an object (evaluating 'navigation.navigate') for the error.
How do I bring back the functionality?
Any help is very appreciated. Here is my project to help;
App.js
import React from 'react';
import TabNavigator from "./assets/component/TabNavigator";
import {StackNavigation} from "./assets/component/StackNavigation";
export default function App() {
return (
<StackNavigation/>
);
}
StackNavigation.js;
import React from 'react';
import { HomeScreen} from "../Screens/HomeScreen";
import LayoutProps from "../Screens/Layout Props";
import SampleViewProps from "../Screens/SampleViewProps";
import {NavigationContainer} from "#react-navigation/native";
import {createNativeStackNavigator} from "#react-navigation/native-stack";
// import ShareExample from "./assets/component/SBShare";
const Stack = createNativeStackNavigator();
export function StackNavigation() {
return (
<NavigationContainer>
<Stack.Navigator initialRouteName="Home">
<Stack.Screen name="Home" component={HomeScreen}/>
<Stack.Screen name="Layout Props" component={LayoutProps} />
<Stack.Screen name="View Props" component={SampleViewProps} />
</Stack.Navigator>
</NavigationContainer>
);
}
HomeScreen.js;
import React from 'react';
import {Button, View, SafeAreaView, StyleSheet} from 'react-native';
import HeaderSB from "../component/SBHeader";
import FooterSB from "../component/SBFooter";
// import ShareExample from "./assets/component/SBShare";
export function HomeScreen({navigation}) {
const receiveValue = (value) => {
console.log("value received from B", value)
}
return (
<>
<SafeAreaView style={styles.container}>
<View style={styles.headerContainer}>
<HeaderSB receiveValue={receiveValue}>
</HeaderSB>
</View>
<View style={styles.mainContent}>
<View style={styles.buttonBox}>
<Button onPress={() => navigation.navigate('Layout Props')} title="Layout Props"/>
<Button onPress={() => navigation.navigate('View Props')} title="View Style Props"/>
</View>
</View>
<View styles={styles.footerContainer}>
<FooterSB receiveValue={receiveValue}>
</FooterSB>
</View>
</SafeAreaView>
</>
);
}
const styles = StyleSheet.create({
container: {
flex: 1,
justifyContent: "space-between",
},
headerContainer: {
},
mainContent: {
},
buttonBox: {}
,
footerContainer: {
},
});
Footer.js;
import * as React from "react";
import {StyleSheet, TouchableOpacity, View} from "react-native";
import {AntDesign, Feather} from "#expo/vector-icons";
import {StackNavigation} from "./StackNavigation";
const FooterSB = ({navigation}) => {
return (
<>
{/* Bottom App Navigation */}
<View style={footerStyle.navCon}>
<View style={footerStyle.navBar}>
{/* Home Button */}
<TouchableOpacity style={footerStyle.home} onPress={() =>
navigation.navigate('Home')}
>
{/* Icon */}
<AntDesign name="home" size={50} color="white"/>
</TouchableOpacity>
{/* Navigation Divider */}
<View style={footerStyle.navDivider}/>
{/* Setting Button */}
<TouchableOpacity style={footerStyle.settings} onPress={() =>
navigation.navigate('Layout Props')}
>
{/* Icon */}
<Feather name="settings" size={50} color="white"/>
</TouchableOpacity>
</View>
</View>
</>
);
}
const footerStyle = StyleSheet.create({
navCon: {
flex: 1,
marginTop: 20,
alignItems: "center",
justifyContent: "flex-end"
},
navBar: {
flexDirection: "row",
justifyContent: "space-evenly",
alignItems: "center",
backgroundColor: "#808080",
width: 500,
height: 50,
},
home: {
// paddingHorizontal: 55,
},
navDivider: {
backgroundColor: "#FFF",
width: 4,
height: 50,
},
settings: {
// marginRight: 107,
// paddingHorizontal: 55,
},
});
export default FooterSB;

If you want navigation as default prop you should add it as <Stack.Screen> but as FooterSB is custom and individual component it doesn't get wrapped with navigation prop automatically.
You need to pass navigation as prop to that so change below
<FooterSB receiveValue={receiveValue}>
</FooterSB>
to
<FooterSB receiveValue={receiveValue} navigation={navigation}>
</FooterSB>
Same way you can pass navigation to header too.

Can someone help me with a React Navigation screen change problem?

I'm having a problem getting my React Navigation to actually transition screens. I've used it successfully before and I cannot figure out what my problem is this time. I click my button and no transition happens. I think it might be a problem with the inline onPress not running....does it have to be in Main Button? Or does the inline code on App.js override anything in MainButton.js.
Also...NarScreen is the screen I'm trying to get to.
FILE 1: App.js
import 'react-native-gesture-handler';
import React from 'react';
import { View, Text, StyleSheet, Image } from 'react-native';
import { NavigationContainer } from '#react-navigation/native';
import { createStackNavigator } from '#react-navigation/stack';
import { color } from 'react-native-reanimated';
import MainButton from './components/MainButton';
import NarScreen from './screens/NarScreen.js'
function HomeScreen({ navigation }) {
return(
<View style={styles.background}>
<View style={styles.logo}>
<Image source={require('./components/HNS1.png')} style={styles.image} resizeMode='contain' />
</View>
<View style={styles.buttons}>
<MainButton onPress={() => navigation.navigate('Nar')}>NAR Test</MainButton>
<MainButton>Tripoli Test</MainButton>
</View>
</View>
);
}
function Nar({ navigation }) {
return(
<NarScreen />
)
}
const Stack = createStackNavigator();
function App() {
return(
<NavigationContainer>
<Stack.Navigator>
<Stack.Screen name="Home" component={HomeScreen} />
<Stack.Screen name="Nar" component={Nar} />
</Stack.Navigator>
</NavigationContainer>
);
}
const styles = StyleSheet.create({
background: {
backgroundColor: '#00629B',
flex: 1,
},
buttons: {
marginTop: "20%",
marginLeft: 10,
},
image: {
width: '80%',
height: 300,
borderRadius: 20,
},
logo: {
borderRadius: 200,
marginTop: '30%',
alignItems: 'center'
},
});
export default App;
File 2: NarScreen.js
import React from 'react';
import { View, Text, Button, StyleSheet } from 'react-native';
const NarScreen = props => {
return(
<View>
<Text>BigScreen!</Text>
</View>
)
}
export default NarScreen;
FILE 3: MainButton.js
import React from 'react';
import {View, Text, StyleSheet, TouchableOpacity, } from 'react-native';
const MainButton = props => {
return <TouchableOpacity>
<View style={styles.button}>
<Text style={styles.buttonText}>{props.children}</Text>
</View>
</TouchableOpacity>
}
const styles = StyleSheet.create({
button: {
backgroundColor: "#FCD757",
paddingVertical: 30,
paddingHorizontal: 30,
height: 100,
width: 300,
marginTop: "10%",
borderRadius: 10,
marginLeft: '12%',
justifyContent: 'space-between',
},
buttonText: {
color: 'black',
fontSize: 26,
textAlign: 'center',
}
})
export default MainButton;

Inside your MainButton.js file, you are not handling onPress event. Add it to touchable opacity.
const MainButton = props => {
return <TouchableOpacity onPress={props.onPress}>
<View style={styles.button}>
<Text style={styles.buttonText}>{props.children}</Text>
</View>
</TouchableOpacity>
}

Rendering another screen in react-native app

I'm experiencing trouble navigating between pages in my react native app. When I attempt to use the button, I get the following error message: TypeError: undefined is not an object (evaluating '_this.props.navigation') I have created my app using numerous js files, and id like to navigate between them using buttons. My App.js file renders to the WelcomeScreen from initializing.
import 'react-native-gesture-handler';
import React from 'react';
import { NavigationContainer } from '#react-navigation/native';
import RecipesList from "cakeapp/app/screens/RecipesList.js";
import { ImageBackground, StyleSheet, View, Text, Button, navigation } from "react-native";
function WelcomeScreen(props) {
return (
<NavigationContainer>
<ImageBackground
style={styles.background}
source={require('cakeapp/app/assets/MainPage.png')}
>
<Text style={styles.text}>MyCakeRecipes</Text>
<View style={styles.homeButton}>
<Button
title="Recipes"
onPress={() => this.props.navigation.navigate('RecipesList')}
/>
</View>
</ImageBackground>
</NavigationContainer>
);
}
const styles = StyleSheet.create({
background: {
flex:1,
justifyContent: "flex-end",
},
text: {
fontSize: 30,
fontWeight: "bold",
color: "white",
textAlign: "center",
bottom: 500,
},
homeButton: {
width: '100%',
height: 40,
backgroundColor: '#5f7f8a'
}
})
export default WelcomeScreen;
import React from 'react';
import { Image, ScrollView, View, Text, } from 'react-native';
const imageDis = {
width: 150,
height: 150
//flex:1,
//justifyContent: "flex-end"
};
const Recipes = () => (
<ScrollView style={{backgroundColor: '#5f7f8a'}}>
<Text style={{ fontSize: 20 }}>Chocolate Cake</Text>
<Image source={require('cakeapp/app/assets/Choc.png')} style={imageDis} />
<Text style={{ fontSize: 20 }}>Chocolate cupcake</Text>
<Image source={require('cakeapp/app/assets/ChocCu.png')} style={imageDis} />
<Text style={{ fontSize: 20 }}>Lemon Cake</Text>
<Image source={require('cakeapp/app/assets/Lemon.png')} style={imageDis} />
<Text style={{ fontSize: 20 }}>Lemom meringue</Text>
<Image source={require('cakeapp/app/assets/LemonM.png')} style={imageDis} />
<Text style={{ fontSize: 20 }}>Chocolate Berry</Text>
<Image source={require('cakeapp/app/assets/ChcoBerry.png')} style={imageDis} />
</ScrollView>
);
export default Recipes

As far as I know, < NavigationContainer> is used in app.js file to define the screens you want to navigate to. And you have to pass navigation as a prop to the component.
Your app.js file should look something like this
const Stack = createStackNavigator();
const App = () => {
return (
<NavigationContainer>
<Stack.Navigator>
<Stack.Screen
name="Welcome"
component={WelcomeScreen}
/>
<Stack.Screen
name="Recipes"
component={RecipesList} />
</Stack.Navigator>
</NavigationContainer>
);
};
And your welcomeScreen like this:
const WelcomeScreen = ({ navigation }) => {
return (
<Button
title="RecipesList"
onPress={() =>
navigation.navigate('RecipesList')
}
/>
);
};
Let me know if it doesnt work

React Native: Unable to navigate to the' Login.js' screen

I have created 3 files and places the navigation container in the app.js file. i am unable to navigate through the screens. I don't understand where the mistake lies.
App.js
import 'react-native-gesture-handler';
import React, { useState } from 'react';
import { NavigationContainer } from '#react-navigation/native';
import Login from './Login.js';
import {createStackNavigator} from '#react-navigation/stack';
import InitialScreen from './InitialScreen.js';
const Stack = createStackNavigator();
function Nav() {
return (
<NavigationContainer>
<Stack.Navigator initialRouteName="InitialScreen">
<Stack.Screen name="Login" component={Login} />
<Stack.Screen name="InitialScreen" component={InitialScreen} />
</Stack.Navigator>
</NavigationContainer>
);
}
export default Nav;
InitialScreen.js
import 'react-native-gesture-handler';
import React, { useState } from 'react';
import {Button, Text, TextInput, View, StyleSheet ,TouchableOpacity,Image} from 'react-native';
import Icon from 'react-native-vector-icons/Feather';
import { NavigationContainer } from '#react-navigation/native';
import Login from './Login.js';
function InitialScreen({navigation}){
const pressHandler=()=>{
navigation.navigate('Login');
}
return (
<>
<View style={styles.container}>
<View style={styles.Container0}>
<TouchableOpacity>
<Text style={{backgroundColor:'white',
fontSize:30,
borderWidth:2,
borderRadius:4,
marginTop: 5,
marginLeft:10,
marginRight:10,
fontWeight:'bold',
textAlign:'center',
padding:2,
}} onPress={pressHandler}
>Login</Text>
<Text style={{marginLeft:10,
fontSize:15,}}> Do not have an account?</Text>
<Text style={{backgroundColor:'white',
fontSize:30,
borderWidth:2,
borderRadius:4,
marginTop: 5,
marginLeft:10,
marginRight:10,
fontWeight:'bold',
textAlign:'center',
padding:2,
}}>SignUp</Text>
</TouchableOpacity>
</View>
<View style={styles.Container1}>
<Image source={{uri: 'http://i.pinimg.com/originals/d1/9b/4d/d19b4d524b8f95b3c640228c28373696.jpg'}}
style={{width:'100%',
height:'100%',
marginTop:5,
flexDirection: 'column',
justifyContent: 'center',
alignSelf: 'center',}}/>
</View>
<View style={styles.Container3}>
<Text style={{fontSize:25,fontWeight:'bold',
color:'white',
textAlign:'center',
}}>I am going to be so productive!!!!!!</Text>
</View>
</View>
<View style={styles.icons}>
<Icon
name='download-cloud'
size={30}
/>
<Icon
name='mail'
size={30}
/>
<Icon
name='instagram'
size={30}
/>
<Icon
name='link'
size={30}
/>
</View>
</>
);
}
const styles=StyleSheet.create({
container:
{ flex:0.9,
marginLeft:5,
marginRight:5,
marginTop:5,
marginBottom:5,
backgroundColor:'black',
},
Container0:
{ flex:0.25,
flexDirection:'column',
backgroundColor:'#ffa07a',
},
Container1:
{
flex:0.6,
backgroundColor:'white',
},
Container3:
{flex:0.1,
justifyContent:"center",
alignItems:'center',
marginTop:10,
},
icons:
{
flex:0.1,
flexDirection: 'row',
justifyContent:'space-around',
marginTop:10,
},
}
);
export default InitialScreen;
Login.js
import 'react-native-gesture-handler';
import React, { useState } from 'react';
import { Text, TextInput, View, StyleSheet ,TouchableOpacity,Image} from 'react-native';
import { NavigationContainer } from '#react-navigation/native';
function Login() {
const [text,onChangeText]= React.useState('Enter your email');
const [Value,setValue]= React.useState('Enter your password');
return(
<View style={styles.container}>
<Text style={{marginTop:40,fontWeight:'bold',fontSize:40,textAlign:'center',}}>Login</Text>
<TextInput
style={{ height: 40, borderColor: 'gray', borderWidth: 1 }}
onChangeText={text => onChangeText(text)}
value={value}
/>
<TextInput
style={{ height: 40, borderColor: 'gray', borderWidth: 1 }}
setValue={Value => setValue(Value)}
value={value}
/>
</View>
);
}
const styles=StyleSheet.create({
container:
{
flexDirection:'column',
}
});
export default Login;
I don't understand why the "onPress" isn't working here . I am unable to even click on it . it is just like a text with no response or change in opacity too . The navigation isn't working either.

#nandita you are using onPress on Text tag. onPress event only works on TouchableOpacity or TouchableHightlight
try doing this.
<TouchableOpacity onPress={pressHandler}>
<Text style={{backgroundColor:'white',
fontSize:30,
borderWidth:2,
borderRadius:4,
marginTop: 5,
marginLeft:10,
marginRight:10,
fontWeight:'bold',
textAlign:'center',
padding:2,
}}
>Login</Text>
<TouchableOpacity>