Custom Controls

Edit

Custom Controls

Shows how to create custom controls.

This example creates a "rotate to north" button.

Copy

index.html<!DOCTYPE html>
<html lang="en">
  <head>
    <title>Custom Controls</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;
      }
      .rotate-north {
        top: 65px;
        left: .5em;
      }
      .ol-touch .rotate-north {
        top: 80px;
      }
    </style>
  </head>
  <body>
    <div id="map" class="map"></div>
    <script src="index.js"></script>
  </body>
</html>

Copy

index.jsimport 'ol/ol.css';
import Map from 'ol/Map';
import View from 'ol/View';
import {defaults as defaultControls, Control} from 'ol/control';
import TileLayer from 'ol/layer/Tile';
import OSM from 'ol/source/OSM';


//
// Define rotate to north control.
//

var RotateNorthControl = /*@__PURE__*/(function (Control) {
  function RotateNorthControl(opt_options) {
    var options = opt_options || {};

    var button = document.createElement('button');
    button.innerHTML = 'N';

    var element = document.createElement('div');
    element.className = 'rotate-north ol-unselectable ol-control';
    element.appendChild(button);

    Control.call(this, {
      element: element,
      target: options.target
    });

    button.addEventListener('click', this.handleRotateNorth.bind(this), false);
  }

  if ( Control ) RotateNorthControl.__proto__ = Control;
  RotateNorthControl.prototype = Object.create( Control && Control.prototype );
  RotateNorthControl.prototype.constructor = RotateNorthControl;

  RotateNorthControl.prototype.handleRotateNorth = function handleRotateNorth () {
    this.getMap().getView().setRotation(0);
  };

  return RotateNorthControl;
}(Control));


//
// Create map, giving it a rotate to north control.
//


var map = new Map({
  controls: defaultControls().extend([
    new RotateNorthControl()
  ]),
  layers: [
    new TileLayer({
      source: new OSM()
    })
  ],
  target: 'map',
  view: new View({
    center: [0, 0],
    zoom: 3,
    rotation: 1
  })
});

Copy

package.json{
  "name": "custom-controls",
  "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"
  }
}