rn-qr-generator

https://www.npmjs.com/package/rn-qr-generator

Getting started

$ npm install rn-qr-generator --save

Mostly automatic installation

$ react-native link rn-qr-generator

---

Important:

Linking is not needed anymore. react-native@0.60.0+ supports dependencies auto linking. For iOS you also need additional step to install auto linked Pods (Cocoapods should be installed):

cd ios && pod install && cd ../

---

Manual installation

iOS

1. In XCode, in the project navigator, right click Libraries ➜ Add Files to [your project's name]
2. Go to node_modules ➜ rn-qr-generator and add RNQrGenerator.xcodeproj
3. In XCode, in the project navigator, select your project. Add libRNQrGenerator.a to your project's Build Phases ➜ Link Binary With Libraries
4. Run your project (Cmd+R)<

Android

1. Open up android/app/src/main/java/[...]/MainActivity.java

• Add import com.gevorg.reactlibrary.RNQrGeneratorPackage; to the imports at the top of the file
• Add new RNQrGeneratorPackage() to the list returned by the getPackages() method

2. Append the following lines to android/settings.gradle:

   rootProject.name = 'MyApp'
   include ':app'
   
   + include ':rn-qr-generator'
   + project(':rn-qr-generator').projectDir = new File(rootProject.projectDir, 	'../node_modules/rn-qr-generator/android')

3. Insert the following lines inside the dependencies block in android/app/build.gradle:

   dependencies {
   + compile project(':rn-qr-generator')
   }

Usage

import RNQRGenerator from 'rn-qr-generator';

RNQRGenerator.generate({
  value: 'https://github.com/gevgasparyan/rn-qr-generator',
  height: 100,
  width: 100,
})
  .then(response => {
    const { uri, width, height, base64 } = response;
    this.setState({ imageUri: uri });
  })
  .catch(error => console.log('Cannot create QR code', error));

// Detect QR code in image
RNQRGenerator.detect({
  uri: PATH_TO_IMAGE
})
  .then(response => {
    const { values } = response; // Array of detected QR code values. Empty if nothing found.
  })
  .catch(error => console.log('Cannot detect QR code in image', error));

generate

input properties

Property	Type	Description
value	string	Text value to be converted into QR image. (required)
width	number	Width of the QR image to be generated. (required)
height	number	Height of the QR image to be generated. (required)
backgroundColor	string	Background color of the image. (white by default)
color	string	Color of the image. (black by default)
fileName	string	Name of the image file to store in FileSystem. (optional)
correctionLevel	string	Data restoration rate for total codewords. Available values are 'L', 'M', 'Q' and 'H'. ('H' by default)
base64	boolean	If true will return base64 representation of the image. (optional, false by default)
padding	Object	Padding params for the image to be generated: {top: number, left: number, bottom: number, right: number}. (default no padding)

payload

Property	Type	Description
uri	string	Path of the generated image.
width	number	Width of the generated image.
height	number	Height of the generated image.
base64	boolean	Base64 encoded string of the image.

detect

input properties

Property	Type	Description
uri	string	Local path of the image. Can be skipped if base64 is passed.
base64	string	Base64 representation of the image to be scanned. If uri is passed this option will be skipped.

payload

Property	Type	Description
values	string[]	Array of detected QR code values. Empty if nothing found.
type	string	Type of detected code.

The following barcode types are currently supported for decoding:

• UPC-A and UPC-E
• EAN-8 and EAN-13
• Code 39
• Code 93
• Code 128
• ITF
• Codabar
• RSS-14 (all variants)
• QR Code
• Data Matrix
• Maxicode
• Aztec ('beta' quality)
• PDF 417 ('beta' quality)

Example of 2FA QR code with Time Based (TOTP) or Counter Based (HOTP)

RNQRGenerator.generate({
  ...
  value: 'otpauth://totp/Example:[e-mail]?secret=HKSWY3RNEHPK3PXP&issuer=Issuer',
})

More information about totp can be found here.

This module uses Zxing library for encoding and decoding codes ( ios, Android).

Note

Some simulators may not generate qr code properly. Use real device if you get an error.