Passing the value from one screen to another is one of the most useful things while we have an application which needs to communicate between the different screens. We can easily pass the data between different activities easily using the this.props.navigation.navigate() which is used to navigate between different screens. In the same method, we can easily pass the value and can get it from other screens.
In our example below, we will pass an input taken from the first screen to the second screen.
To pass the value between different activities
- Pass params to a route by putting them in an object as a second parameter to the
navigation.navigatefunction from First Screen. Using :1this.props.navigation.navigate('RouteName', { /* params go here */ }) - Read the params in your Second screen. Using:1this.props.navigation.getParam(paramName, defaultValue)
To Make a React Native App
Getting started with React Native will help you to know more about the way you can make a React Native project. We are going to use react-native init to make our React Native App. Assuming that you have node installed, you can use npm to install the react-native-cli command line utility. Open the terminal and go to the workspace and run
npm install -g react-native-cliRun the following commands to create a new React Native project
react-native init ProjectNameIf you want to start a new project with a specific React Native version, you can use the --version argument:
react-native init ProjectName --version X.XX.Xreact-native init ProjectName --version react-native@nextThis will make a project structure with an index file named App.js in your project directory.
Installation of Dependencies
To use createStackNavigator you need to install react-navigation and react-native-gesture-handler dependencies.
To install these dependencies open the terminal and jump into your project
1 | cd ProjectName |
Run the following commands
1 | npm install react-navigation --save |
1 | npm install react-native-gesture-handler --save |
This command will copy all the dependencies into your node_module directory. –save is optional, it is just to update dependencies in your package.json file.
CocoaPods Installation
After the updation of React Native 0.60, they have introduced autolinking so we do not require to link the library but need to install pods. So to install pods use
1 | cd ios && pod install && cd .. |
Project File Structure
To start with this Example you need to create a directory named pages in your project and create two files FirstPge.js and SecondPage.js in it.
Now open App.js in any code editor and replace the code with the following code.
App.js
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 | //This is an example code to pass values between two screens using React Navigator// import React, { Component } from 'react'; //import react in our code. //For React Navigation Version 2+ //import {createStackNavigator} from 'react-navigation'; //For React Navigation Version 3+ import {createStackNavigator,createAppContainer} from 'react-navigation'; //import Navigator in our project import FirstPage from './pages/FirstPage'; import SecondPage from './pages/SecondPage'; //import all the screens we are going to switch const App = createStackNavigator({ //Constant which holds all the screens like index of any book FirstPage: { screen: FirstPage }, //First entry by default be our first screen //if we do not define initialRouteName SecondPage: { screen: SecondPage }, }, { initialRouteName: 'FirstPage', } ); //For React Navigation Version 2+ //export default App; //For React Navigation Version 3+ export default createAppContainer(App); |
Open pages/FirstPage.js in any code editor and the Replace the code with the following code.
FirstPage.js
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 | // First screen which we will use to send the data import React, { Component } from 'react'; //import react in our code. import { StyleSheet, View, Button, TextInput } from 'react-native'; //import all the components we are going to use. export default class FirstPage extends Component { constructor(props) { //constructor to set default state super(props); this.state = { username: '', }; } static navigationOptions = { //Setting the header of the screen title: 'First Page', }; render() { const { navigate } = this.props.navigation; return ( //View to hold our multiple components <View style={styles.container}> {/*Input to get the value from the user*/} <TextInput value={this.state.username} onChangeText={username => this.setState({ username })} placeholder={'Enter Any value'} style={styles.input} /> {/*Button to go to the next activity*/} <Button title="Go Next" //Button Title onPress={() => navigate('SecondPage', { JSON_ListView_Clicked_Item: this.state.username, }) } //On click of the button we will send //the data as a Json from here to the Second Screen using navigation prop /> </View> ); } } const styles = StyleSheet.create({ container: { flex: 1, backgroundColor: '#fff', alignItems: 'center', padding: 16, }, input: { width: 200, height: 44, padding: 10, marginBottom: 10, backgroundColor: '#DBDBD6', }, }); |
Open pages/SecondPage.js in any code editor and the Replace the code with the following code.
SecondPage.js
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 | // Second screen which we will use to get the data import React, { Component } from 'react'; //import react in our code. import { StyleSheet, View, Text } from 'react-native'; //import all the components we are going to use. export default class SecondPage extends Component { static navigationOptions = { //Setting the header of the screen title: 'Second Page', }; render() { const { navigate } = this.props.navigation; return ( //View to hold our multiple components <View style={styles.container}> <Text> You are on SecondPage and the value passed from the first screen is </Text> {/*Using the navigation prop we can get the value passed from the first Screen*/} <Text style={styles.TextStyle}> {this.props.navigation.state.params.JSON_ListView_Clicked_Item} </Text> <Text style={{ marginTop: 16 }}>With Check</Text> {/*If you want to check the value is passed or not, you can use conditional operator.*/} <Text style={styles.TextStyle}> {this.props.navigation.state.params.JSON_ListView_Clicked_Item ? this.props.navigation.state.params.JSON_ListView_Clicked_Item : 'No Value Passed'} </Text> </View> ); } } const styles = StyleSheet.create({ container: { flex: 1, backgroundColor: '#fff', margin: 50, alignItems: 'center', justifyContent: 'center', }, TextStyle: { fontSize: 23, textAlign: 'center', color: '#f00', }, }); |
To Run the React Native App
Open the terminal again and jump into your project using.cd ProjectNamereact-native run-androidreact-native run-ios (macOS only).
This is how you can pass the value from one screen to another screen. If you have any doubt or you want to share something about the topic you can comment below or contact us here. There will be more posts coming soon. Stay tuned!
Hope you liked it. 🙂
it was very useful. Now i want to know how to implement conditional operator in this. Once we entered value the value will be displayed in the next page.. now i want to know that if we didn’t enter the value an empty screen display in the second page so for that i want to show an invalid value instead of it.. can you help me out of this…
If the value is empty then instead of applying an conditional operator in react navigation you can check the value before and the can generate the alert accordingly. To check the value you can take the help from the following example..
https://aboutreact.com/react-native-check-textinput-is-empty-or-not/
this is fine if i want to pass the value from first screen to 3rd screen what should i do?th same method is not working
You have to take the value from 2nd to 3rd again..
For example you have took the value from 1st to 2nd and then take it in a variable and while navigating to 3rd you have to take the value again..
Instead you can also see asyncstorage..
have you found solution for it?
I have already answered that.
It works perfectly. Now i want to add a button in the second page that goes back to the first page. already there is a back arrow in the second page but i need a button in second page that return to first page
You can use the same way that you have used while switching from first screen to second screen. Like
navigate(‘FirstPage’)} />
You can find the Example here
https://aboutreact.com/refresh-previous-screen-react-navigation/
i got the solution for that….
Good the hear that 🙂
This is fine but how to pass the value from first page to 3rd or 4th page
You can not directly send the data to the 3rd and 4th screen you have to take the data in the middle screen and pass the same from there also. You can also use async storage to store the value and you can access those values any time.
i wanna take value from 1 to 3 page.
i am passing 1 to 2 and 2 to 3 its not working, how to do that using react native navigation
What is the error it is showing?