feat: 延时加载引擎sdk

public/index.html

@@ -7,15 +7,10 @@
     <meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1, user-scalable=no">
     <link rel="icon" href="<%= BASE_URL %>favicon.ico">
     <script src="./config.js"></script>
-    
+
     <!-- <link href="./lib/Cesium/Widgets/widgets.css" rel="stylesheet" /> -->
     <link href="./lib/sycim/sycim.min.css" rel="stylesheet" />
-    <script src="./lib/sycim/sycim.min.js"></script>
-    <script>
-      window.Cesium = sycim.Cesium;
-      sycim.config.baseUrl = "./lib/sycim/resources/";
-    </script>
-    <script src="./lib/SuperMap3D/SuperMap3D.js"></script>
+
     <title><%= webpackConfig.name %></title>
 
 	  <style>
@@ -214,5 +209,23 @@
 		    <div class="load_title">正在加载系统资源，请耐心等待</div>
         </div>
 	</div>
+  <script>
+    function downloadJs(url){
+      var script = document.createElement('script');
+      script.type = 'text/javascript'
+      script.src = url;
+      document.body.appendChild(script);
+    }
+    window.onload = function(){
+      console.log('window.onload')
+      downloadJs('./lib/sycim/sycim.min.js');
+      setTimeout(() => {
+
+        window.Cesium = sycim.Cesium;
+        sycim.config.baseUrl = "./lib/sycim/resources/";
+        downloadJs('./lib/SuperMap3D/SuperMap3D.js');
+      }, 500);
+    }
+  </script>
   </body>
 </html>