Accessible Map

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Accessible Map

Example of an accessible map.

This page's map element has its tabindex attribute set to "0", that makes it focusable. To focus the map element you can either navigate to it using the "tab" key or use the skip link. When the map element is focused the + and - keys can be used to zoom in and out and the arrow keys can be used to pan.

Clicking on the "Zoom in" and "Zoom out" buttons below the map zooms the map in and out. You can navigate to the buttons using the "tab" key, and press the "enter" key to trigger the zooming action.

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index.html<!DOCTYPE html>
<html lang="en">
  <head>
    <title>Accessible Map</title>
    <!-- The line below is only needed for old environments like Internet Explorer and Android 4.x -->
    <script src="https://cdn.polyfill.io/v2/polyfill.min.js?features=requestAnimationFrame,Element.prototype.classList,URL"></script>
    <style>
      .map {
        width: 100%;
        height:400px;
      }
      a.skiplink {
        position: absolute;
        clip: rect(1px, 1px, 1px, 1px);
        padding: 0;
        border: 0;
        height: 1px;
        width: 1px;
        overflow: hidden;
      }
      a.skiplink:focus {
        clip: auto;
        height: auto;
        width: auto;
        background-color: #fff;
        padding: 0.3em;
      }
      #map:focus {
        outline: #4A74A8 solid 0.15em;
      }
    </style>
  </head>
  <body>
    <a class="skiplink" href="#map">Go to map</a>
    <div id="map" class="map" tabindex="0"></div>
    <button id="zoom-out">Zoom out</button>
    <button id="zoom-in">Zoom in</button>
    <script src="index.js"></script>
  </body>
</html>

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index.jsimport 'ol/ol.css';
import Map from 'ol/Map';
import View from 'ol/View';
import TileLayer from 'ol/layer/Tile';
import OSM from 'ol/source/OSM';


var map = new Map({
  layers: [
    new TileLayer({
      source: new OSM()
    })
  ],
  target: 'map',
  view: new View({
    center: [0, 0],
    zoom: 2
  })
});

document.getElementById('zoom-out').onclick = function() {
  var view = map.getView();
  var zoom = view.getZoom();
  view.setZoom(zoom - 1);
};

document.getElementById('zoom-in').onclick = function() {
  var view = map.getView();
  var zoom = view.getZoom();
  view.setZoom(zoom + 1);
};

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package.json{
  "name": "accessible",
  "dependencies": {
    "ol": "6.1.1"
  },
  "devDependencies": {
    "parcel": "1.11.0"
  },
  "scripts": {
    "start": "parcel index.html",
    "build": "parcel build --experimental-scope-hoisting --public-url . index.html"
  }
}