This post will give you a basic Understanding of React Native switch. React Native Switch is a component for getting/showing boolean value or to select from one out of two.
A Switch is a controlled component that requires a callback onValueChange that updates the value prop in order for the component to reflect user actions. If the value prop is not updated, the component will continue to render the supplied value prop instead of the expected result of any user actions.
To Import Switch in Code
1 | import { Switch} from 'react-native' |
Render Using
1 | <Switch onValueChange = {handlerHere} value = {Pre decided value if any}/> |
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.
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 27 28 29 30 31 32 33 34 35 36 | //This is an example code to understand Switch// import React from 'react'; //import react in our code. import { Switch, Text, View, StyleSheet } from 'react-native'; //import all the components we are going to use. export default class App extends React.Component { //Initial state false for the switch. You can change it to true just to see. state = {switchValue:false} toggleSwitch = (value) => { //onValueChange of the switch this function will be called this.setState({switchValue: value}) //state changes according to switch //which will result in re-render the text } render() { return ( <View style={styles.container}> {/*Text to show the text according to switch condition*/} <Text>{this.state.switchValue?'Switch is ON':'Switch is OFF'}</Text> {/*Switch with value set in constructor*/} {/*onValueChange will be triggered after switch condition changes*/} <Switch style={{marginTop:30}} onValueChange = {this.toggleSwitch} value = {this.state.switchValue}/> </View> ); } } const styles = StyleSheet.create({ container: { flex: 1, justifyContent: 'center', alignItems: 'center', } }); |
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).
That was the React Native Switch. If you have any doubt or you want to share something about the topic you can comment below or contact us here. The remaining components will be covered in the next article. Stay tuned!
Hope you liked it. 🙂