Customizable QR code generated for React & React Native


Keywords
qrcode, react, react-native
License
MIT
Install
npm install react-fancy-qrcode@1.0.4

Documentation

QR Code Generator for React and React Native

Creates a stylish QR code for both React (web) & React Native.

This project was inspired by react-native-qrcode-svg.

Install

With Yarn

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

Or with npm

npm install -S react-fancy-qrcode react-native-svg

For React native and iOS, you'll need to perform a pod-install:

npx pod-install ios

Example

<QRCode
  value={"https://github.com/jgillick/react-fancy-qrcode"}
  size={400}
  dotScale={0.8}
  dotRadius="50%"
  positionRadius={["5%", "1%"]}
  errorCorrection="H"
  logo={require("images/fire.png")}
/>

Component Properties

Name Default Description
value "" The value to encode into the QR code
size 100 The pixel width/height of the generated QR code
margin 0 Space around the QR code (useful if you're generating an image with it)
logo - Image to place in the center of the QR code (either {uri: 'base64string'}, require('pathToImage'), or URL string)
logoSize - The size to make the logo. Defaults to 20% of the size prop. (if it covers more than 20%, QR code data might be lost)
backgroundColor white The QR code background color
color black Primary foreground color of the QR code. If the value is an array of strings, it's treated as a linear gradient
colorGradientDirection ['0%', '0%', '100%', '100%'] If color is defined as a linear gradient, this defines the gradient direction. Array format: [x1, y1, x2, y2]
positionColor - Color of the positioning squares in the top-left, top-right, and bottom-left. Defaults to the color property
positionGradientDirection ['0%', '0%', '100%', '100%'] See colorGradientDirection explanation.
positionRadius 0 The radius of the positioning pattern squares. See examples below.
dotScale 1.0 Scale down the dots by setting this to a value between .1 - 1.
dotRadius 0 The corner radius of each dot as a pixel or percent
errorCorrection M QR Code error correction mode (more info)

Export QR code image data

React Native

You can use a ref to download the image data from the root SVG element (via react-native-svg).

import React, { useCallback, useRef } from 'react';
import QRCode, { QRCodeRef } from 'react-fancy-qrcode';

function RenderQRCode() {

  const svgRef = useRef<QRCodeRef>();
  const download = useCallback(() => {
    svgRef.current?.toDataURL((data) => {
      console.log(data);
    })
  }, [svgRef.current])

  return (
    <QRCode
      ref={svgRef}
      value={"https://github.com/jgillick/react-fancy-qrcode"}
      size={400}
    />
  )
}

Web

On web you cannot export the binary SVG data but you can get the SVG source. In theory you could then use a JavaScript SVG -> PNG converter (like canvg) to convert the SVG source to an image.

Here's an example of getting the SVG source:

import React, { useCallback, useRef } from 'react';
import QRCode, { QRCodeRef } from 'react-fancy-qrcode';

function RenderQRCode() {

  const svgRef = useRef<QRCodeRef>();
  const download = useCallback(() => {
    const svgSource = svgRef.current?.outerHTML;
    console.log(svgSource);
  }, [svgRef.current])

  return (
    <QRCode
      ref={svgRef}
      value={"https://github.com/jgillick/react-fancy-qrcode"}
      size={400}
    />
  )
}

Prop: positionRadius - Positioning Pattern Square Corner Radius

The three large squares in the QR code (top-left, top-right, bottom-left) are used by QR code readers to determine the position of the QR code. NOTE: If you customize the squares too much, QR code readers might not recognize the QR code.

If defined as a single pixel/percent value, this will be used for all 3 patters, both outside and inside squares.

<QRCode
  positionRadius="5%"
  value={"https://github.com/jgillick/react-fancy-qrcode"}
  size={400}
/>

If defined as an array, the first index is for the outer square and the second is for the inner square of each pattern.

<QRCode
  positionRadius={["20%", 10]}
  value={"https://github.com/jgillick/react-fancy-qrcode"}
  size={400}
/>

You can also define each radius as an object with an rx and ry value (learn more)

<QRCode
  positionRadius={{ rx: "5%", ry: "10%" }}
  value={"https://github.com/jgillick/react-fancy-qrcode"}
  size={400}
/>

or

<QRCode
  positionRadius={[
    { rx: "5%", ry: "10%" },
    { rx: 1, ry: 20 },
  ]}
  value={"https://github.com/jgillick/react-fancy-qrcode"}
  size={400}
/>

Linear Gradient

<QRCode
  value={"https://github.com/jgillick/react-fancy-qrcode"}
  size={300}
  color={["#2BC0E4", "#EAECC6"]}
  positionColor="#348AC7"
/>