OpenLayers v4.2.0 -----地图延迟加载；

官方：http://openlayers.org/en/latest/examples/lazy-source.html

<!DOCTYPE html>
<html>
  <head>
    <title>Lazy Source</title>
    <link rel="stylesheet" href="https://openlayers.org/en/v4.2.0/css/ol.css" type="text/css">
    <!-- 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>
    <script src="https://openlayers.org/en/v4.2.0/build/ol.js"></script>
    <style>
       button.code {
         font-family: Monaco,Menlo,Consolas,"Courier New",monospace;
         font-size: 12px;
         padding: 5px;
         margin: 0 5px;
       }    </style>
  </head>
  <body>
    <div id="map" class="map"></div>
    <button id="set-source" class="code">layer.setSource(source)</button>
    <button id="unset-source" class="code">layer.setSource(null)</button>
    <script>
      var source = new ol.source.OSM();

      var layer = new ol.layer.Tile();

      var map = new ol.Map({
        layers: [layer],
        target: 'map',
        view: new ol.View({
          center: [0, 0],
          zoom: 2
        })
      });

      document.getElementById('set-source').onclick = function() {
        layer.setSource(source);
      };

      document.getElementById('unset-source').onclick = function() {
        layer.setSource(null);
      };
    </script>
  </body>
</html>

 

posted @ 2017-07-01 14:33  lishidefengchen  阅读(460)  评论(0)  编辑  收藏  举报