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A QR Code generator for React Native based on react-native-svg and node-qrcode.

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Expensify/react-native-qrcode-svg

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react-native-qrcode-svg

A QR Code generator for React Native based on react-native-svg and javascript-qrcode.

Discussion: https://discord.gg/RvFM97v

Features

  • Easily render QR code images
  • Optionally embed a logotype
Android iOS

Installation

Install dependency packages

yarn add react-native-svg react-native-qrcode-svg

Or

npm i -S react-native-svg react-native-qrcode-svg

If you are using React Native 0.60.+ go to the folder your-project/ios and run pod install, and you're done.

If not, use one of the following method to link.

Link with react-native link

If you are using React Native <= 0.59.X, link the native project:

react-native link react-native-svg

Examples

import QRCode from 'react-native-qrcode-svg';

// Simple usage, defaults for all but the value
render() {
  return (
    <QRCode
      value="http://awesome.link.qr"
    />
  );
};
// 30px logo from base64 string with transparent background
render() {
  let base64Logo = 'data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAOEAA..';
  return (
    <QRCode
      value="Just some string value"
      logo={{uri: base64Logo}}
      logoSize={30}
      logoBackgroundColor='transparent'
    />
  );
};
// 20% (default) sized logo from local file string with white logo backdrop
render() {
  let logoFromFile = require('../assets/logo.png');
  return (
    <QRCode
      value="Just some string value"
      logo={logoFromFile}
    />
  );
};
// get base64 string encode of the qrcode (currently logo is not included)
getDataURL() {
  this.svg.toDataURL(this.callback);
}

callback(dataURL) {
  console.log(dataURL);
}

render() {
  return (
    <QRCode
      value="Just some string value"
      getRef={(c) => (this.svg = c)}
    />
  );
}

Props

Name Default Description
size 100 Size of rendered image in pixels
value 'this is a QR code' String Value of the QR code. Can also accept an array of segments as defined in Manual mode. Ex. [{ data: 'ABCDEFG', mode: 'alphanumeric' }, { data: '0123456', mode: 'numeric' }, { data: [253,254,255], mode: 'byte' }]
color 'black' Color of the QR code
backgroundColor 'white' Color of the background
enableLinearGradient false enables or disables linear gradient
linearGradient ['rgb(255,0,0)','rgb(0,255,255)'] array of 2 rgb colors used to create the linear gradient
gradientDirection [170,0,0,0] the direction of the linear gradient
logo null Image source object. Ex. {uri: 'base64string'} or {require('pathToImage')}
logoSize 20% of size Size of the imprinted logo. Bigger logo = less error correction in QR code
logoBackgroundColor backgroundColor The logo gets a filled quadratic background with this color. Use 'transparent' if your logo already has its own backdrop.
logoMargin 2 logo's distance to its wrapper
logoBorderRadius 0 the border-radius of logo image (Android is not supported)
quietZone 0 quiet zone around the qr in pixels (useful when saving image to gallery)
getRef null Get SVG ref for further usage
ecl 'M' Error correction level
onError(error) undefined Callback fired when exception happened during the code generating process

Saving generated code to gallery

Note: Experimental only ( not tested on iOS) , uses getRef() and needs RNFS module

npm install --save react-native-fs

Example for Android:

import { CameraRoll , ToastAndroid } from "react-native"
import RNFS from "react-native-fs"
...

  saveQrToDisk() {
   	this.svg.toDataURL((data) => {
   		RNFS.writeFile(RNFS.CachesDirectoryPath+"/some-name.png", data, 'base64')
   		  .then((success) => {
   			  return CameraRoll.saveToCameraRoll(RNFS.CachesDirectoryPath+"/some-name.png", 'photo')
   		  })
   		  .then(() => {
   			  this.setState({ busy: false, imageSaved: true  })
   			  ToastAndroid.show('Saved to gallery !!', ToastAndroid.SHORT)
   		  })
   	})
  }

Development and testing

This library comes with an Example App. You can find it in the directory ./Example.
Use the app to easily test your changes to react-native-qrcode-svg and when developing new features.

Read more details in the dedicated README.

Dependencies

PeerDependencies

Dependencies