QR.Flutter is a Flutter library for simple and fast QR code rendering via a Widget or custom painter.

Features #

• Built on QR - Dart
• Automatic QR code version/type detection or manual entry
• Supports QR code versions 1 - 40
• Error correction / redundancy
• Configurable output size, padding, background and foreground colors
• Supports image overlays
• Export to image data to save to file or use in memory
• No internet connection required

Installing #

You should add the following to your pubspec.yaml file:

dependencies:
  qr_flutter: ^3.1.0

Note: If you're using the Flutter master channel, if you encounter build issues, or want to try the latest and greatest then you should use the master branch and not a specific release version. To do so, use the following configuration in your pubspec.yaml:

dependencies:
  qr_flutter:
    git:
      url: git://github.com/lukef/qr.flutter.git

Keep in mind the master branch could be unstable.

After adding the dependency to your pubspec.yaml you can run: flutter packages get or update your packages using your IDE.

Getting started #

To start, import the dependency in your code:

import 'package:qr_flutter/qr_flutter.dart';

Next, to render a basic QR code you can use the following code (or something like it):

QrImage(
  data: "1234567890",
  version: QrVersions.auto,
  size: 200.0,
),

Depending on your data requirements you may want to tweak the QR code output. The following options are available:

Examples #

There is a simple, working, example Flutter app in the /example directory. You can use it to play with all the options.

Also, the following examples give you a quick overview on how to use the library.

A basic QR code will look something like:

QrImage(
  data: 'This is a simple QR code',
  version: QrVersions.auto,
  size: 320,
  gapless: false,
)

A QR code with an image (from your application's assets) will look like:

QrImage(
  data: 'This QR code has an embedded image as well',
  version: QrVersions.auto,
  size: 320,
  gapless: false,
  embeddedImage: AssetImage('assets/images/my_embedded_image.png'),
  embeddedImageStyle: QrEmbeddedImageStyle(
    size: Size(80, 80),
  ),
)

To show an error state in the event that the QR code can't be validated:

QrImage(
  data: 'This QR code will show the error state instead',
  version: 1,
  size: 320,
  gapless: false,
  errorStateBuilder: (cxt, err) {
    return Container(
      child: Center(
        child: Text(
          "Uh oh! Something went wrong...",
          textAlign: TextAlign.center,
        ),
      ),
    );
  },
)

FAQ #

Has it been tested in production? Can I use it in production? #

Yep! It's stable and ready to rock. It's currently in use in quite a few production applications including:

• Sixpoint: Android & iOS

Outro #

Credits #

Thanks to Kevin Moore for his awesome QR - Dart library. It's the core of this library.

For author/contributor information, see the AUTHORS file.

License #

QR.Flutter is released under a modified MIT license. See LICENSE for details.