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pass value from one componet to another in react natve

i am trying to pass value from login and register into dashbord since sign is a unique compont i dont know how to pass log from login and register can someone help
sign.js
export default function Sign({navigation}) {
async function onGoogleButtonPress() {
await GoogleSignin.hasPlayServices();
const userInfo = await GoogleSignin.signIn();
setuserInfo(userInfo);
navigation.navigate('dash', {userInfo});
}
return (
<View style={styles.prheight}>
<View style={styles.buttonw}>
<GoogleSigninButton
style={{width: 192, height: 48}}
size={GoogleSigninButton.Size.Wide}
color={GoogleSigninButton.Color.Light}
onPress={onGoogleButtonPress}
// disabled={this.state.isSigninInProgress}
/>
</View>
</View>
);
}
register.js
export default function Register(props) {
return (
<View style={styles.prheight}>
<View style={styles.buttonw}>
<Sign navigation={props.navigation} log={name:"register"} />
</View>
</View>
);
}
login
export default function login(props) {
return (
<View style={styles.prheight}>
<View style={styles.buttonw}>
<Sign navigation={props.navigation} log={name:"login"} />
</View>
</View>
dash.js
export default function dash(props) {
const [text, setTextbaby] = useState();
const {userInfo} = props?.route?.params;
console.log(props.log);

You should pass log prop in Sign component and take it like this.
export default function Sign({ navigation, log }) {
async function onGoogleButtonPress() {
await GoogleSignin.hasPlayServices();
const userInfo = await GoogleSignin.signIn();
setuserInfo(userInfo);
navigation.navigate('dash', {userInfo, log});
}
// some code
}
after all, log will be located inside props.route.params object
export default function dash(props) {
const [text, setTextbaby] = useState();
const {userInfo, log} = props?.route?.params;
console.log(log);
}
UPDATED: use double brackets (in order to pass object)
log={{name: "register"}}
log={{name: "login"}}

we can pass a value from one screen to another screen through async-storage react-navigation or declare a value globally.
To pass a value from login to dashboard I recommend you to see this async-storage Docs https://react-native-async-storage.github.io/async-storage/docs/install
async-storage store a value in App while React navigation does not store a value in App, React navigation just transfer value from one screen to another.
react navigation Docs https://reactnavigation.org/docs/navigating/
passing a value from one component to another
import { Text, View, Button } from 'react-native';
import { NavigationContainer } from '#react-navigation/native';
import { createNativeStackNavigator } from '#react-navigation/native-stack';
function HomeScreen({ navigation }) {
return (
<View style={{ flex: 1, alignItems: 'center', justifyContent: 'center' }}>
<Text>Home Screen</Text>
<Button
title="Go to Details"
onPress={() => {
/* 1. Navigate to the Details route with params */
navigation.navigate('Details', {
itemId: 86,
otherParam: 'anything you want here',
});
}}
/>
</View>
);
}
function DetailsScreen({ route, navigation }) {
/* 2. Get the param */
const { itemId } = route.params;
const { otherParam } = route.params;
return (
<View style={{ flex: 1, alignItems: 'center', justifyContent: 'center' }}>
<Text>Details Screen</Text>
<Text>itemId: {JSON.stringify(itemId)}</Text>
<Text>otherParam: {JSON.stringify(otherParam)}</Text>
<Button
title="Go to Details... again"
onPress={() =>
navigation.push('Details', {
itemId: Math.floor(Math.random() * 100),
})
}
/>
<Button title="Go to Home" onPress={() => navigation.navigate('Home')} />
<Button title="Go back" onPress={() => navigation.goBack()} />
</View>
);
}
const Stack = createNativeStackNavigator();
export default function App() {
return (
<NavigationContainer>
<Stack.Navigator>
<Stack.Screen name="Home" component={HomeScreen} />
<Stack.Screen name="Details" component={DetailsScreen} />
</Stack.Navigator>
</NavigationContainer>
);
}```

The text is not output to the form

I'm new to react native, trying to write a small project (notebook). I implemented the buttons, they all work, but when I save an entry to the form, nothing is displayed and does not give errors.
import { StatusBar } from 'expo-status-bar';
import { StyleSheet, Modal, Text, View, ScrollView, TextInput, Image, Button } from 'react-native';
import { Ionicons } from '#expo/vector-icons';
import React, {useState} from 'react';
import { Formik } from 'formik';
export default function App() {
const [news, setnews] = useState([
{name: '', text: ''}
]);
const addArtical = (artical) => {
setnews((list) => {
artical.key = Math.random().toString();
return[
artical,
...list
]
});
setModalWindow(false);
}
const [modalWindow, setModalWindow] = useState(false);
return (
<View style={styles.container}>
<Text style={styles.title}>Main tasks:</Text>
<ScrollView horizontal={true} showsHorizontalScrollIndicator={false}>
<View style={styles.up}>
<View style={styles.cub}></View>
<View style={styles.cub}></View>
<View style={styles.cub}></View>
<View style={styles.cub}></View>
<View style={styles.cub}></View>
<View style={styles.cub}></View>
</View>
</ScrollView>
<ScrollView vertical={true} showsVerticalScrollIndicator={false}>
<View style={styles.all}>
<TextInput style={styles.d} placeholder=' Search'></TextInput>
<Text style={styles.titletwo}>Other tasks:</Text>
<Ionicons style={styles.ic} name="add" size={30} color="black" onPress={() => setModalWindow(true)}/>
</View>
<Modal visible={modalWindow}>
<Ionicons style={styles.ic} name="close" size={30} color="black" onPress={() => setModalWindow(false)}/>
<View>
<Formik initialValues={{name: '', text: ''}} onSubmit={(values, clean) => {
addArtical(values);
clean.resetForm();
}}>
{(props) => (
<View >
<TextInput value={props.values.name} placeholder='Name' onChangeText={props.handleChange('name')}/>
<TextInput value={props.values.text} multiline placeholder='Text' onChangeText={props.handleChange('text')}/>
<Button title='Add' onPress={props.handleSubmit}/>
</View>
)}
</Formik>
</View>
</Modal>
</ScrollView>
</View>
);
}
Read more: I click add entry, a field opens with the addition of text, fill in the field with the necessary information, save, everything is successful, but my entry is nowhere

How can I send text taken from user to another screen to display it in <text> in react native? (I am a beginner)

App.js
function App() {
const [getScreen, showScreen] = useState(false);
const [getEmail, setEmail] = useState("");
return (
<View>
<LoginScreen />
<LoginContexts.Provider
value={{ getEmail, setEmail, getScreen, showScreen }}
>
{showScreen ? <Screen2 /> : <LoginScreen />}
</LoginContexts.Provider>
</View>
);
}
export default App;
Login
function LoginScreen({ navigation }) {
const { getEmail, setEmail, showScreen } = useContext(LoginContexts);
function gotEmail(inputEmail) {
setEmail(inputEmail);
}
return (
<View style={styles.container}>
<Text style={styles.loginText}>Login</Text>
<View style={styles.textInput}>
<TextInput
placeholder="Please enter your email"
defaultValue={getEmail}
onChange={gotEmail}
/>
</View>
<View style={styles.space} />
<View style={styles.passwordStyle}>
<TextInput
placeholder="password"
secureTextEntry
autoCorrect={false}
autoCapitalize="none"
/>
</View>
<View style={styles.space} />
<View>
<Button
style={styles.loginBTN}
title="Login"
onPress={() => {
showScreen(true);
}}
/>
</View>
</View>
);
}
export default LoginScreen;
Screen 2
function Screen2() {
const { getEmail } = useContext(LoginContexts);
return (
<View style={{ flex: 1, alignItems: "center", justifyContent: "center" }}>
<Text>{getEmail}</Text>;
</View>
);
}
export default Screen2;
LoginContext <-- used context api
import { createContext } from "react";
export const LoginContexts = createContext({});
Could you please tell me that why data is not going to another page?
I used useContext but I am not able to send data to another page. Please help me to solve this problem.
In this I had taken input from user as email and I want to display that email in text view in another page but I am unable to do that. On button click nothing happens.

TypeError: undefined is not an object (evaluating '_this.props.navigation') in React Native

I'm trying to work with React Navigation using an external button component, to make styling it easier, but it gives me the TypeError: undefined is not an object (evaluating '_this.props.navigation') error when I try to pass the navigation. If I create the button on my home screen it works fine, but that clutters up my HomeScreen's stylesheet, and means I have to repeat code when I use the button elsewhere.
I have the stack navigation set up in my App.js, and again, it works fine when I'm not trying to pass the navigation as a prop.
Here's HomeScreen.js
import React from "react";
import {
ScrollView,
StyleSheet,
Text,
View,
AsyncStorage,
} from 'react-native';
import Heading from '../heading';
import Input from '../Input';
import Button from "../Button";
export const Home = ({navigation}) => (
<View style={styles.container}>
<ScrollView style={styles.content}>
<Heading />
</ScrollView>
<Button/>
</View>
)
And here's my Button.js
/* eslint-disable prettier/prettier */
import React from 'react';
import {
StyleSheet,
Text,
View,
TouchableHighlight
} from 'react-native';
import { useNavigation } from '#react-navigation/native';
function Button(){
const navigation = useNavigation()
return(
<View style={styles.buttonContainer}>
<TouchableHighlight
underlayColor='rgba(175, 47, 47, .75)'
activeOpacity={1.0}
style={styles.button}
onPress={() => {
navigation.navigate("New Medication");
}}>
<Text style={styles.submit}>
+
</Text>
</TouchableHighlight>
</View>
)
}
As far as I understand it, this should work just fine, so why is it saying that it's being passed as undefined?
UPDATE: Thanks to some suggestions I now have it to where it doesn't give an error, just does nothing.
Here's my App.js, with my navigation
const Stack = createStackNavigator();
function MyStack() {
return (
<Stack.Navigator
screenOptions={{
headerShown: false
}}>
<Stack.Screen name="Home" component={Home} />
<Stack.Screen name="NewMedication" component={newMedScreen} />
</Stack.Navigator>
);
}
class App extends Component{
render(){
return(
<NavigationContainer>
<MyStack />
</NavigationContainer>
);
}
}
export default App;

I recommend you to create a const with screen name and reuse it everywhere to avoid such problem. You nave stack like this <Stack.Screen name="NewMedication" component={newMedScreen} /> , but try to navigate
navigation.navigate("New Medication").Of course this screen do not exist
const NEW_MEDICATION_SCREEN = 'NewMedication'
<Stack.Screen name={NEW_MEDICATION_SCREEN} component={newMedScreen} />
.....
onPress={() => navigation.navigate(NEW_MEDICATION_SCREEN)}>
and for make Button reusable use it like this
function Button({onPress}){
return(
<View style={styles.buttonContainer}>
<TouchableHighlight
underlayColor='rgba(175, 47, 47, .75)'
activeOpacity={1.0}
style={styles.button}
onPress={onPress}>
<Text style={styles.submit}>
+
</Text>
</TouchableHighlight>
</View>
)}
export const Home = ({navigation}) => (
<View style={styles.container}>
<ScrollView style={styles.content}>
<Heading />
</ScrollView>
<Button onPress={() => navigation.navigate(NEW_MEDICATION_SCREEN)}/>
</View>

In React Native Navigation, how do I send props to my screens?

I want to be able to use navigation on a different screen other than just the first one but I am getting an error that this.props does not exist.
I have my App.js file setup like this:
import { createStackNavigator } from '#react-navigation/stack';
import { NavigationContainer } from '#react-navigation/native';
import Screen2 from './screens/Screen2';
import Screen3 from './screens/Screen3';
import HomeScreen from './screens/HomeScreen';
const Stack = createStackNavigator();
function HomeScreen({ navigation }) {
return (
<View>
<Button
title="Go to Screen2"
onPress={() => {
navigation.navigate('Screen2');
}}
/>
<Button
title="Go to Screen3"
onPress={() => {
navigation.navigate('Screen3');
}}
/>
</View>
);
const App: () => React$Node = () => {
return (
<NavigationContainer>
<Stack.Navigator>
<Stack.Screen name="Home" component={HomeScreen} />
<Stack.Screen name="Screen2" component={Screen2} />
<Stack.Screen name="Screen3" component={Screen3} />
</Stack.Navigator>
</NavigationContainer>
);
};
The buttons in app.js work but if I go to Screen2 and click a button that intends to go to another (Screen3 in the example below), props does not exist.
Example Screen2.js would look like this:
const Screen2: () => React$Node = () => {
return (
<>
<View style={{ flex: 1 }}>
<Button
title="Go to Screen3"
onPress={goToScreen3}}
/>
</View>
</>
);
function goToScreen3() {
if(condition){
this.props.navigate.navigate('Screen3');
}}
How do I pass the props so that I can use navigation in my second screen?

For functional component sometimes it's tricky to pass navigation through props as well. So just use withNavigation.
you have to import it and wrap the function with it.
import { withNavigation } from 'react-navigation';
const Screen2 = props => {
const goToScreen3 = () => {
if(condition){
props.navigate.navigate('Screen3');
}}
return (
<>
<View style={{ flex: 1 }}>
<Button
title="Go to Screen3"
onPress={goToScreen3()}
/>
</View>
</>
);
export default withNavigation(Screen2)

In Functional Component there is no this binding so you need to get the props from the function first
check th
const Screen2 = (props) => {
return (
<>
<View style={{ flex: 1 }}>
<Button
title="Go to Screen3"
onPress={goToScreen3}}
/>
</View>
</>
);
function goToScreen3() {
if(condition){
props.navigate.navigate('Screen3');
}
}
}