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    @ntoand/react-qr-scanner

    0.0.8 • Public • Published

    npm version

    Introduction

    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. Thanks to initial repo https://github.com/JodusNodus/react-qr-reader

    Demo

    kybarg.github.io/react-qr-scanner/

    Known Issues

    • Due to browser implementations the camera can only be accessed over https or localhost.
    • Not compatible with macOS/iOS Safari. Use legacyMode to support these platforms.
    • In Firefox a prompt will be shown to the user asking which camera to use, so facingMode will not affect it.

    Install

    npm install --save react-qr-scanner

    Example

    import React, { Component } from 'react'
    import QrReader from 'react-qr-scanner'
     
    class Test extends Component {
      constructor(props){
        super(props)
        this.state = {
          delay: 100,
          result: 'No result',
        }
     
        this.handleScan = this.handleScan.bind(this)
      }
      handleScan(data){
        this.setState({
          result: data,
        })
      }
      handleError(err){
        console.error(err)
      }
      render(){
        const previewStyle = {
          height: 240,
          width: 320,
        }
     
        return(
          <div>
            <QrReader
              delay={this.state.delay}
              style={previewStyle}
              onError={this.handleError}
              onScan={this.handleScan}
              />
            <p>{this.state.result}</p>
          </div>
        )
      }
    }

    Props

    onScan

    Type: function, Required, Argument: result

    Scan event handler. Called every scan with the decoded value or null if no QR code was found.

    onError

    Type: function, Required, Argument: error

    Function to call when an error occurs such as:

    • Not supported platform
    • The lack of available devices

    onLoad

    Type: function, Optional

    Called when the component is ready for use.

    onImageLoad

    Type: function, Optional, Argument: React img onLoad event

    Called when the image in legacyMode is loaded.

    delay

    Type: number, Optional, Default: 500

    The delay between scans in milliseconds. To disable the interval pass in false.

    facingMode

    Type: string, Optional

    Specify which camera direction should be used (if available). Options: front and rear.

    legacyMode

    Type: boolean, Optional, Default: false.

    If the device does not allow camera access (e.g. IOS Browsers, Safari) you can enable legacyMode to allow the user to take a picture (On a mobile device) or use an existing one. To trigger the image dialog just call the method openImageDialog from the parent component. Warning You must call the method from a user action (eg. click event on some element).

    maxImageSize

    Type: number, Optional, Default: 1500.

    If legacyMode is active then the image will be downscaled to the given value while keepings its aspect ratio. Allowing larger images will increase the accuracy but it will also slow down the processing time.

    style

    Type: object, Optional

    Styling for the preview element. This will be a video or an img when legacymode is true. Warning The preview will keep its aspect ratio, to disable this set the CSS property objectFit to fill.

    className

    Type: string, Optional

    ClassName for the container element.

    chooseDeviceId

    Type: function, Optional, Arguments: (1) video devices matching facingMode, (2) all video devices

    Called when choosing which device to use for scanning. By default chooses the first video device matching facingMode, if no devices match the first video device found is choosen.

    Dev

    Install dependencies

    npm install

    Build

    npm run build

    Demo

    npm run storybook

    Test

    npm test

    Linting

    npm run lint

    Tested platforms

    • Chrome 56 and Firefox 53 on macOs 10.12
    • Chrome 55 and Firefox 50 on Android 6.0.1

    License

    The MIT License (MIT)

    Copyright (c) 2017 Thomas Billiet

    Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

    The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

    Install

    npm i @ntoand/react-qr-scanner

    DownloadsWeekly Downloads

    1

    Version

    0.0.8

    License

    MIT

    Unpacked Size

    2.59 MB

    Total Files

    25

    Last publish

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