This example uses OpenLayers v10.9.0. The latest is v.
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#### Loading Spinner

events 3 loading 8 spinner 1

#####

Example using load events to show a loading spinner.

You can listen for the map's `loadstart` and `loadend` events to show a loading spinner on top of the map.

##### main.js

    import Map from 'ol/Map.js';
    import View from 'ol/View.js';
    import TileLayer from 'ol/layer/Tile.js';
    import ImageTile from 'ol/source/ImageTile.js';

    const key = 'Get your own API key at https://www.maptiler.com/cloud/';
    const attributions =
      '<a href="https://www.maptiler.com/copyright/" target="_blank">&copy; MapTiler</a> ' +
      '<a href="https://www.openstreetmap.org/copyright" target="_blank">&copy; OpenStreetMap contributors</a>';

    const source = new ImageTile({
      attributions: attributions,
      url: 'https://api.maptiler.com/maps/streets-v2/{z}/{x}/{y}.png?key=' + key,
      tileSize: 512,
    });

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

    map.on('loadstart', function () {
      map.getTargetElement().classList.add('spinner');
    });
    map.on('loadend', function () {
      map.getTargetElement().classList.remove('spinner');
    });

##### index.html

    <!DOCTYPE html>
    <html lang="en">
      <head>
        <meta charset="UTF-8">
        <title>Loading Spinner</title>
        <link rel="stylesheet" href="node_modules/ol/ol.css">
        <style>
          .map {
            width: 100%;
            height: 400px;
          }
          .map {
            background: #85ccf9;
            position: relative;
          }
          #map {
            height: 400px;
            position: relative;
          }

          @keyframes spinner {
            to {
              transform: rotate(360deg);
            }
          }

          .spinner:after {
            content: "";
            box-sizing: border-box;
            position: absolute;
            top: 50%;
            left: 50%;
            width: 40px;
            height: 40px;
            margin-top: -20px;
            margin-left: -20px;
            border-radius: 50%;
            border: 5px solid rgba(180, 180, 180, 0.6);
            border-top-color: rgba(0, 0, 0, 0.6);
            animation: spinner 0.6s linear infinite;
          }
        </style>
      </head>
      <body>
        <div id="map" class="map"></div>

        <script type="module" src="main.js"></script>
      </body>
    </html>

##### package.json

    {
      "name": "load-events",
      "dependencies": {
        "ol": "10.9.0"
      },
      "devDependencies": {
        "vite": "^3.2.3"
      },
      "scripts": {
        "start": "vite",
        "build": "vite build"
      }
    }