JSFiddle - React, Tailwind, and code Playground

by jipexu

HTML

<link rel="stylesheet" href="https://cdn.jsdelivr.net/gh/openlayers/openlayers.github.io@master/en/v6.9.0/css/ol.css">
<script src="https://cdn.jsdelivr.net/gh/openlayers/openlayers.github.io@master/en/v6.9.0/build/ol.js"></script>
<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8">
    <title>Draw and Modify Features</title>
    <link rel="stylesheet" href="https://cdn.jsdelivr.net/gh/openlayers/openlayers.github.io@master/en/v6.9.0/css/ol.css" />
    <script src="https://cdn.jsdelivr.net/gh/openlayers/openlayers.github.io@master/en/v6.9.0/build/ol.js"></script>
    <!-- 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>
    <form class="form-inline">
      <label for="type">Geometry type &nbsp;</label>
      <select id="type">
        <option value="Point">Point</option>
        <option value="LineString">LineString</option>
        <option value="Polygon">Polygon</option>
        <option value="Circle">Circle</option>
      </select>
    </form>
    <script src="main.js"></script>
  </body>
</html>

CSS

.tooltip {
  position: relative;
  padding: 3px;
  background: rgba(0, 0, 0, 0.5);
  color: white;
  opacity: 0.7;
  white-space: nowrap;
  font: 10pt sans-serif;
}

JavaScript

import 'ol/ol.css';
import Map from 'ol/Map';
import View from 'ol/View';
import {Circle as CircleStyle, Fill, Stroke, Style} from 'ol/style';
import {Draw, Modify, Snap} from 'ol/interaction';
import {OSM, Vector as VectorSource} from 'ol/source';
import {Tile as TileLayer, Vector as VectorLayer} from 'ol/layer';

const raster = new TileLayer({
  source: new OSM(),
});

const source = new VectorSource();
const vector = new VectorLayer({
  source: source,
  style: new Style({
    fill: new Fill({
      color: 'rgba(255, 255, 255, 0.2)',
    }),
    stroke: new Stroke({
      color: '#ffcc33',
      width: 2,
    }),
    image: new CircleStyle({
      radius: 7,
      fill: new Fill({
        color: '#ffcc33',
      }),
    }),
  }),
});

const map = new Map({
  layers: [raster, vector],
  target: 'map',
  view: new View({
    center: [-11000000, 4600000],
    zoom: 4,
  }),
});

const modify = new Modify({source: source});
map.addInteraction(modify);

let draw, snap; // global so we can remove them later
const typeSelect = document.getElementById('type');

function addInteractions() {
  draw = new Draw({
    source: source,
    type: typeSelect.value,
  });
  map.addInteraction(draw);
  snap = new Snap({source: source});
  map.addInteraction(snap);
}

/**
 * Handle change event.
 */
typeSelect.onchange = function () {
  map.removeInteraction(draw);
  map.removeInteraction(snap);
  addInteractions();
};

addInteractions();