rn-qr-generator

rn-qr-generator

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

React Native QR Code generator and reader library supporting both the New Architecture (TurboModules/Fabric) and the legacy architecture.

Version Compatibility

Version	React Native	Architecture Support
2.x.x	>= 0.71.0	New Architecture (TurboModules) + Legacy
1.x.x	>= 0.55.0	Legacy Architecture only

Note: If you're using React Native < 0.71.0 or need to stay on the legacy architecture, use version 1.4.5:

npm install rn-qr-generator@1.4.5

Getting started

npm install rn-qr-generator --save
# or
yarn add rn-qr-generator

iOS Installation

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

New Architecture (React Native 0.71+)

This library automatically supports the New Architecture when enabled in your project. No additional configuration is required.

For iOS: Make sure you have RCT_NEW_ARCH_ENABLED=1 in your Podfile or environment.

For Android: Make sure you have newArchEnabled=true in your gradle.properties.

Manual installation (Legacy)

iOS

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

Android

• 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

• 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')
  

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

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

Usage

import RNQRGenerator from 'rn-qr-generator';

// Generate QR Code
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));

TypeScript Support

This library includes TypeScript definitions out of the box:

import RNQRGenerator, { 
  QRCodeGenerateOptions, 
  QRCodeGenerateResult,
  QRCodeDetectOptions,
  QRCodeScanResult 
} from 'rn-qr-generator';

const options: QRCodeGenerateOptions = {
  value: 'Hello World',
  width: 200,
  height: 200,
  correctionLevel: 'H',
};

const result: QRCodeGenerateResult = await RNQRGenerator.generate(options);

API Reference

generate

Generates a QR code image from the provided value.

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)

Response

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	string	Base64 encoded string of the image (if requested).

detect

Detects QR codes in an image.

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.

Response

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

Supported Barcode Types

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

2FA QR Code Example

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.

Migration from 1.x to 2.x

Version 2.0.0 adds support for React Native's New Architecture (TurboModules). The JavaScript API remains the same, so migration should be seamless:

• Update the package:

  npm install rn-qr-generator@latest
  # or
  yarn upgrade rn-qr-generator
  

• For iOS, run:

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

• For Android, rebuild your app.

Breaking Changes:

• Minimum React Native version is now 0.71.0
• Minimum iOS version is now 13.0
• Minimum Android SDK version is now 21

Dependencies

This module uses ZXing library for encoding and decoding codes:

• iOS: ZXingObjC
• Android: zxing-core

Troubleshooting

Simulator Issues

Some simulators may not generate QR codes properly. Use a real device if you get an error.

New Architecture Issues

If you encounter issues with the New Architecture:

• Make sure your React Native version is 0.71.0 or higher
• Verify that the New Architecture is properly enabled in your project
• Clean and rebuild your project:

  # iOS
  cd ios && pod install && cd ..
  npx react-native run-ios
  
  # Android
  cd android && ./gradlew clean && cd ..
  npx react-native run-android
  

License

MIT