ArcGIS For Flex地图联动

1地图联动介绍

是针对Map对象，利用观察者模式，当鼠标进入某一Map时，此Map对象成为主体，其他的Map对其进行观察，若其当前视图范围改变，其他Map随其而动，同时取消对该Map对象的监听。

2具体实现

Map对象具有EXTENT_CHANGE事件

（com.esri.ags.events.ExtentEvent中），监听此事件进行观察。

3具体代码

package Hymn

{

              import com.esri.ags.Map;

              import com.esri.ags.events.ExtentEvent;

             

              import flash.events.MouseEvent;

             

              publicclass LinkingMethodsClass

              {

                publicfunction LinkingMethodsClass()

                {

                    MapItems = new Array();

                }

                privatevar MapItems:Array;

    /**

     <p>功能：添加需要联动地图对象。</p>

     <p>参数：

     MapItem Map对象</p>

     <p>返回值：无</p>

     */

                publicfunction AddMap(MapItem:Map):void

                {

                    for each(var Mapadded:Map inthis.MapItems)

                    {

                        if(Mapadded == MapItem)

                        {

                            return;

                        }

                    }

                    MapItems.push(MapItem);

                    AddLinkingStartFunction(MapItem);

                }

                privatefunction AddLinkingStartFunction(MapItem:Map):void

                {

                    MapItem.addEventListener(MouseEvent.MOUSE_OVER,CheckExtentStartFunction);

                }

                privatefunction CheckExtentStartFunction(event:MouseEvent):void

                {

                    var MapItem:Map = event.currentTarget as Map;

                    addLinkingFunction(MapItem);

                }

                privatefunction addLinkingFunction(MapItem:Map):void

                {

                    MapItem.addEventListener(ExtentEvent.EXTENT_CHANGE,DoLinkingFunction);

                }

                privatefunction DoLinkingFunction(event:ExtentEvent):void

                {

                    var MapItem:Map = event.currentTarget as Map;

                    RemoveLinkingFunction();

                    addLinkingFunction(MapItem);

                    for each(var MapValue:Map inthis.MapItems)

                    {

                        if(MapValue!=MapItem)

                        {

                            MapValue.extent = MapItem.extent;

                        }

                    }

                }

                privatefunction RemoveLinkingFunction():void

                {

                    for each(var MapItem:Map inthis.MapItems)

                    {

                        MapItem.removeEventListener(ExtentEvent.EXTENT_CHANGE,DoLinkingFunction);

                    }

                }

              }

}

4 应用示例

新建Flex工程后，将以下代码粘贴覆盖主运行程序中的代码。

<?xml version="1.0" encoding="utf-8"?>

<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"

   creationComplete="Intial(event)"

   xmlns:s="library://ns.adobe.com/flex/spark"

   xmlns:mx="library://ns.adobe.com/flex/mx" minWidth="955"

   minHeight="600" xmlns:esri="http://www.esri.com/2008/ags">

  <fx:Script>

    <![CDATA[

      import Hymn.LinkingMethodsClass;

      import mx.events.FlexEvent;

      privatevar MapLikingItem:LinkingMethodsClass

      protectedfunction Intial(event:FlexEvent):void

      {

        // TODO Auto-generated method stub

        MapLikingItem = new LinkingMethodsClass();

        MapLikingItem.AddMap(this.MapItem1);

        MapLikingItem.AddMap(this.MapItem2);

      }

    ]]>

  </fx:Script>

  <s:VGroup width="100%" height="100%" >

    <esri:Map id="MapItem1" >

      <esri:ArcGISTiledMapServiceLayer

        url="http://hanym-pc/ArcGIS/rest/services/地形图/MapServer"/>

    </esri:Map>

    <esri:Map id="MapItem2" >

      <esri:ArcGISTiledMapServiceLayer

        url="http://hanym-pc/ArcGIS/rest/services/地形图/MapServer"/>

    </esri:Map>

  </s:VGroup> 

</s:Application>