ArcGIS api for javascript——明确的创建图层列表

描述

本例展示了如何确切地创建一个地图服务里的图层列表。这个列表由HTML checkboxe组成，可用用于开关图层的可见性。

函数updateLayerVisibility()包含开关图层的逻辑。函数循环访问列表里的每个图层，依赖checkbox状态图层是否应该可见，并且使用 ArcGISDynamicMapServiceLayer.setVisibleLayers()更新相应图层可见性。

如果需要创建地图服务里的所有图层的图层列表，见示例动态地创建图层列表.

 1 <%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
 2 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
 3 <html>
 4   <head>
 5     <meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>
 6     <meta http-equiv="X-UA-Compatible" content="IE=7" />
 7     <title>明确的创建图层列表</title>
 8     <link rel="stylesheet" type="text/css" href="http://serverapi.arcgisonline.com/jsapi/arcgis/1.6/js/dojo/dijit/themes/tundra/tundra.css">
 9     <script type="text/javascript" src="http://serverapi.arcgisonline.com/jsapi/arcgis/?v=1.6"></script>
10      <script type="text/javascript">
11         dojo.require("esri.map");
12         
13         var dynamicMapServiceLayer,map,visible = [];
14         
15         function init() {
16         
17             map = new esri.Map("map");
18             
19             var imageParameters = new esri.layers.ImageParameters();
20             imageParameters.visibleLayers = [0,1,2];
21             
22             dynamicMapServiceLayer=new esri.layers.ArcGISDynamicMapServiceLayer(
23             "http://sampleserver1.arcgisonline.com/ArcGIS/rest/services/Specialty/ESRI_StatesCitiesRivers_USA/MapServer", {"imageParameters":imageParameters}
24             );
25             map.addLayer(dynamicMapServiceLayer);
26         } 
27     
28         
29         function updateLayerVisibility() {      
30             var inputs = dojo.query(".list_item"), input;
31             //在这个应用中，图层 2是一只可见的
32             visible = [2];
33             for( var i=0,j=inputs.length;i<j;i++) {
34                 if(inputs[i].checked) {
35                     visible.push(inputs[i].id);
36                 }
37             
38             }
39             dynamicMapServiceLayer.setVisibleLayers(visible);
40                                    
41         }  
42         
43     
44        dojo.addOnLoad(init);
45     </script>
46  
47   </head>
48 
49   <body >
50   This sample loads an ArcGISDynamicMapServiceLayer and presents check boxes for only the layers that should be toggled on and off by users.  <br />ed to toggle their visibility.<br />
51     <br />
52       Layer List: <span id="layer_list"><input type="checkbox" class="list_item" checked="checked" id='0' value=0 onclick="updateLayerVisibility();"/>Cities&nbsp;&nbsp;
53           <input type="checkbox" class="list_item" checked="checked" id="1" value=1 onclick="updateLayerVisibility();"/>River&nbsp;&nbsp;
54           
55       </span><br />
56       <br />
57       <div id="map" class="tundra" style=" 900px;height: 600px;border: 1px solid #000"></div>
58   </body>
59 </html>