Generation of QR Code in React Native

QR Code Generation

If we have to share any small data between different users, we can use the QR Code. Generation of QR Code in React Native is very easy as we just have to install react-native-svg and react-native-qrcode-svg package, which will provide <QRCode/> component to make QRCode.

QR Code is known as Quick Response Code is a trademark for a two-dimensional barcode. QR Code is a machine/camera readable block enabled code for encoding numeric value and alphabetic value. The QR Code stores information within a block of images and can store multiple types of information.

How to use QRCode Component?

<QRCode
  //QR code value
  value={this.state.valueForQRCode}
  //size of QR Code
  size={250}
  //Color of the QR Code (Optional)
  color="black"
  //Background Color of the QR Code (Optional)
  backgroundColor="white"
  //Logo of in the center of QR Code (Optional)
  logo={{
    url:
      'https://raw.githubusercontent.com/AboutReact/sampleresource/master/logosmalltransparen.png',
  }}
  //Center Logo size  (Optional)
  logoSize={30}
  //Center Logo margin (Optional)
  logoMargin={2}
  //Center Logo radius (Optional)
  logoBorderRadius={15}
  //Center Logo background (Optional)
  logoBackgroundColor="yellow"
/>

In this example, we are making a TextInput to get the value for QR Code and after clicking on “Generate QR Code” it will generate the QR Code.

You can also see how to make Barcode and QR Code Scanner using Camera in React Native.

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-cli

Run the following commands to create a new React Native project

react-native init ProjectName

If 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.X

react-native init ProjectName --version react-native@next

This will make a project structure with an index file named App.js in your project directory.

Installation of Dependency

Open the terminal and jump into your project

cd ProjectName

1. We need to install react-native-svg dependency to have SVG support

npm install react-native-svg --save

2. To use QRCode you need to install react-native-qrcode-svg dependency

npm install react-native-qrcode-svg --save

This command will copy all the dependencies into your node_module directory. –save is optional, it is just to update the react-navigation dependency 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. To install the pods use

cd ios && pod install && cd ..

Code for the Generation of QR Code

Now Open App.js in any code editor and replace the code with the following code.

App.js

//This is an example code to generate QR code//
import React, { Component } from 'react';
//import react in our code.
import {
  StyleSheet,
  View,
  TextInput,
  TouchableOpacity,
  Text,
} from 'react-native';
// import all basic components
import QRCode from 'react-native-qrcode-svg';

class App extends Component {
  constructor() {
    super();
    this.state = {
      inputValue: '',
      // Default Value of the TextInput
      valueForQRCode: '',
      // Default value for the QR Code
    };
  }
  getTextInputValue = () => {
    // Function to get the value from input
    // and Setting the value to the QRCode
    this.setState({ valueForQRCode: this.state.inputValue });
  };
  render() {
    return (
      <View style={styles.MainContainer}>
        <QRCode
          //QR code value
          value={this.state.valueForQRCode ? this.state.valueForQRCode : 'NA'}
          //size of QR Code
          size={250}
          //Color of the QR Code (Optional)
          color="black"
          //Background Color of the QR Code (Optional)
          backgroundColor="white"
          //Logo of in the center of QR Code (Optional)
          logo={{
            url:
              'https://raw.githubusercontent.com/AboutReact/sampleresource/master/logosmalltransparen.png',
          }}
          //Center Logo size  (Optional)
          logoSize={30}
          //Center Logo margin (Optional)
          logoMargin={2}
          //Center Logo radius (Optional)
          logoBorderRadius={15}
          //Center Logo background (Optional)
          logoBackgroundColor="yellow"
        />
        <TextInput
          // Input to get the value to set on QRCode
          style={styles.TextInputStyle}
          onChangeText={text => this.setState({ inputValue: text })}
          underlineColorAndroid="transparent"
          placeholder="Enter text to Generate QR Code"
        />
        <TouchableOpacity
          onPress={this.getTextInputValue}
          activeOpacity={0.7}
          style={styles.button}>
          <Text style={styles.TextStyle}> Generate QR Code </Text>
        </TouchableOpacity>
      </View>
    );
  }
}
export default App;
const styles = StyleSheet.create({
  MainContainer: {
    flex: 1,
    margin: 10,
    alignItems: 'center',
    paddingTop: 40,
  },
  TextInputStyle: {
    width: '100%',
    height: 40,
    marginTop: 20,
    borderWidth: 1,
    textAlign: 'center',
  },
  button: {
    width: '100%',
    paddingTop: 8,
    marginTop: 10,
    paddingBottom: 8,
    backgroundColor: '#F44336',
    marginBottom: 20,
  },
  TextStyle: {
    color: '#fff',
    textAlign: 'center',
    fontSize: 18,
  },
});

To Run the React Native App

Open the terminal again and jump into your project using.

cd ProjectName

To run the project on an Android Virtual Device or on real debugging device

react-native run-android

or on the iOS Simulator by running

react-native run-ios (macOS only).

Output Screenshots

That was the React Native Generate QR Code. If you have any doubts 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. 🙂