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Extent Interaction

Extent4 interaction4 box2

Using an Extent interaction to draw an extent.

This example shows how to use an Extent interaction to draw a modifiable extent.

Use Shift+Drag to draw an extent. Shift+Drag on the corners or edges of the extent to resize it. Shift+Click off the extent to remove it.

main.js
import 'ol/ol.css';
import ExtentInteraction from 'ol/interaction/Extent';
import GeoJSON from 'ol/format/GeoJSON';
import Map from 'ol/Map';
import View from 'ol/View';
import {OSM, Vector as VectorSource} from 'ol/source';
import {Tile as TileLayer, Vector as VectorLayer} from 'ol/layer';
import {shiftKeyOnly} from 'ol/events/condition';

const vectorSource = new VectorSource({
  url: 'data/geojson/countries.geojson',
  format: new GeoJSON(),
});

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

const extent = new ExtentInteraction({condition: shiftKeyOnly});
map.addInteraction(extent);
index.html
<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8">
    <title>Extent Interaction</title>
    <!-- Pointer events polyfill for old browsers, see https://caniuse.com/#feat=pointer -->
    <script src="https://unpkg.com/elm-pep"></script>
    <!-- The line below is only needed for old environments like Internet Explorer and Android 4.x -->
    <script src="https://cdn.polyfill.io/v3/polyfill.min.js?features=fetch,requestAnimationFrame,Element.prototype.classList,URL,TextDecoder,Number.isInteger"></script>
    <style>
      .map {
        width: 100%;
        height:400px;
      }
    </style>
  </head>
  <body>
    <div id="map" class="map"></div>
    <script src="main.js"></script>
  </body>
</html>
package.json
{
  "name": "extent-interaction",
  "dependencies": {
    "ol": "6.8.1"
  },
  "devDependencies": {
    "parcel": "^2.0.0-beta.1"
  },
  "scripts": {
    "start": "parcel index.html",
    "build": "parcel build --public-url . index.html"
  }
}