A QR code generation library for Dart and Flutter.

Features #

• Supports QR code versions 1 - 40
• Error correction / redundancy

Getting started #

To start, import the dependency in your code:

import 'package:qr/qr.dart';

To build your QR code data you should do so as such:

final qrCode = QrCode(4, QrErrorCorrectLevel.L)
  ..addData('Hello, world in QR form!');
final qrImage = QrImage(qrCode);

Now you can use your qrImage instance to render a graphical representation of the QR code. A basic implementation would be as such:

for (var x = 0; x < qrImage.moduleCount; x++) {
  for (var y = 0; y < qrImage.moduleCount; y++) {
    if (qrImage.isDark(y, x)) {
      // render a dark square on the canvas
    }
  }
}

See the example directory for further details.

Pre-made UI libraries #

The following libraries use qr.dart to generate QR codes for you out of the box:

qr_flutter - A Flutter Widget to render QR codes

barcode - A package that supports many types of scannable codes, include QR.

Demo #

A working demo can be found here: kevmoo.github.io/qr.dart