react-camera-qr

1.0.1 • Public • Published

Introduction

This is fork from react-qr-reader2, which in turn is a fork of another package - react-qr-reader.

This fork of the package will focus more on supporting modern phones using PWAs, updating the outdated code from the original fork and focus on only using the environment facing cameras to scan QR codes. This is because it is rare for camera scan usage to involve front facing cameras. For now all support is being focused on Android Chrome and Safari iOS. Support for Firefox, and desktop environments may work but is not the focus of this package for now.

PRs welcome and encouraged :)

Original package description below A React component for reading QR codes from the webcam. It uses the WebRTC standards for reading webcam data and jsQR is used for detecting QR codes in that data. To optimise the speed and experience, a web-worker is used to offload the heavy QR code algorithm on a separate process. The web worker is inlined and loaded on creation of the component.

Known Issues

  • Currently the Storybook example does not seem to work.
  • Server side rendering won't work so only require the componont when rendering in a browser environment.
  • Due to browser implementations the camera can only be accessed over https or localhost.
  • In Firefox a prompt will be shown to the user asking which camera to use, so facingMode will not affect it.
  • On IOS 11 it is only supported on Safari and not on Chrome or Firefox due to Apple making the API not available to 3rd party browsers.
  • Camera won't open in iOS PWA Apps. https://stackoverflow.com/questions/46228218/how-to-access-camera-on-ios11-home-screen-web-app

Install

yarn install --save react-camera-qr

Example

import React, { Component } from 'react'
import QrReader from 'react-camera-qr'
 
class Test extends Component {
  state = {
    result: 'No result'
  }
 
  handleScan = data => {
    if (data) {
      this.setState({
        result: data
      })
    }
  }
  handleError = err => {
    console.error(err)
  }
  render() {
    return (
      <div>
        <QrReader
          delay={300}
          onError={this.handleError}
          onScan={this.handleScan}
          style={{ width: '100%' }}
        />
        <p>{this.state.result}</p>
      </div>
    )
  }
}
 

Props

Events

Prop Argument Description
onScan result and chunks Scan event handler. Called every scan with the decoded value in first parameter and with chunks array in second parameter. result is null and chunks is empty array if no QR code was found.
onError Error Called when an error occurs.
onLoad object Called when the component is ready for use. Object properties are mirrorVideo: boolean, streamTrack: object

Options

Prop Type Default Description
delay number or false 500 The delay between scans in milliseconds. To disable the interval pass in false.
facingMode user or environment environment Specify which camera should be used (if available).
resolution number 600 The resolution of the video. Larger resolution will increase the accuracy but it will also slow down the processing time.
style a valid React style none Styling for the container element. Warning The preview will always keep its 1:1 aspect ratio.
className string none ClassName for the container element.
showViewFinder boolean true Show or hide the build in view finder. See demo
constraints object null Use custom camera constraints that the override default behavior. MediaTrackConstraints
chosenCamera string '' By using the enumerateDevices function you can pass a device ID directly to the camera instead of using the default.

Dev

Install dependencies

yarn install

Build

yarn run build

Demo

yarn run storybook

Linting

yarn run lint

Tested platforms

  • Chrome Android
  • Safari iOS

Package Sidebar

Install

npm i react-camera-qr

Weekly Downloads

57

Version

1.0.1

License

MIT

Unpacked Size

179 kB

Total Files

20

Last publish

Collaborators

  • mcallistertyler95