<iron-a11y-keys>
iron-a11y-keys provides a cross-browser interface for processing keyboard commands. The interface adheres to WAI-ARIA best practices. It uses an expressive syntax to filter key presses.
See: Documentation, Demo.
Usage
Installation
npm install --save @polymer/iron-a11y-keys
 
In an html file
<html>
  <head>
    <script type="module">
      import '@polymer/iron-a11y-keys/iron-a11y-keys.js';
    </script>
  </head>
  <body>
    <iron-a11y-keys id="keys" keys="left right down up"></iron-a11y-keys>
    <script>
      // Where to listen for the keys.
      keys.target = document.body;
      keys.addEventListener('keys-pressed', function(event) {
        console.log(event.detail);
      });
    </script>
  </body>
</html> 
In a Polymer 3 element
import {PolymerElement, html} from '@polymer/polymer';
import '@polymer/iron-a11y-keys/iron-a11y-keys.js';
class SampleElement extends PolymerElement {
  static get properties() {
    return {
      target: {
        type: Object,
        value: function() {
          return this.$.input;
        }
      },
    }
  }
  static get template() {
    return html`
      <iron-a11y-keys id="a11y"
          target="[[target]]" keys="enter"
          on-keys-pressed="onEnter"></iron-a11y-keys>
      <input id="input" placeholder="Type something. Press enter. Check console.">
    `;
  }
  function onEnter() {
    console.log(this.userInput);
  }
}
customElements.define('sample-element', SampleElement); 
Contributing
If you want to send a PR to this element, here are the instructions for running the tests and demo locally:
Installation
git clone https://github.com/PolymerElements/iron-a11y-keys
cd iron-a11y-keys
npm install
npm install -g polymer-cli 
Running the demo locally
polymer serve --npm
open http://127.0.0.1:<port>/demo/ 
Running the tests
polymer test --npm