<granite-qrcode-decoder>

A custom element to decode a QR Code from an image, using a modified version of Lazersoft's jsqrcode library, to allow jsqrcode to deal with ShadowDOM

Built on lit-element following the open-wc recommendation.

The old Polymer 2.x-1.x version is available on the polymer-hybrid branch.

Installation

npm i granite-qrcode-decoder

Usage

The element can decode several sources of images:

• A dataURL, by using the dataUrl property
• An app-media-image-capture, by injecting it to the blob property
• A canvas, by calling the decodeCanvas method passing the canvas as parameter

<script type="module">
  import 'granite-qrcode-decoder/granite-qrcode-decoder.js';
</script> 
 
<granite-qrcode-decoder
    @qrcode-decoded="${method_listening_for_data}"
    data-url="data:image/jpeg;base64,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" 
    debug></granite-qrcode-decoder>

Linting with ESLint, Prettier, and Types

To scan the project for linting errors, run

npm run lint

You can lint with ESLint and Prettier individually as well

npm run lint:eslint

npm run lint:prettier

To automatically fix many linting errors, run

npm run format

You can format using ESLint and Prettier individually as well

npm run format:eslint

npm run format:prettier

Testing with Karma

To run the suite of karma tests, run

npm run test

To run the tests in watch mode (for TDD, for example), run

npm run test:watch

Demoing with Storybook

To run a local instance of Storybook for your component, run

npm run storybook

To build a production version of Storybook, run

npm run storybook:build

Tooling configs

For most of the tools, the configuration is in the package.json to reduce the amount of files in your project.

If you customize the configuration a lot, you can consider moving them to individual files. \

Local Demo with es-dev-server

npm start

To run a local development server that serves the basic demo located in demo/index.html

Contributing

1. Fork it!
2. Create your feature branch: git checkout -b my-new-feature
3. Commit your changes: git commit -m 'Add some feature'
4. Push to the branch: git push origin my-new-feature
5. Submit a pull request :D

License

MIT License