用ArcGIS Server Flex API调用Google Map的地图数据，原理是通过访问Google Map地图服务的切片数据，重载ArcGIS Server Felx API的TiledMapServiceLayer接口类，实现了对于Googlemap影像切片数据、道路等POI切片数据、矢量切片数据以及地形数据的接入。

1．重载TiledMapServiceLayer接口类实现google地图的加载

本例中将该类放在放到了src/com/esri/viewer目录下。

package com.esri.viewer
{
    import com.esri.ags.SpatialReference;
    import com.esri.ags.geometry.Extent;
    import com.esri.ags.geometry.MapPoint;
    import com.esri.ags.layers.TiledMapServiceLayer;
    import com.esri.ags.layers.supportClasses.LOD;
    import com.esri.ags.layers.supportClasses.TileInfo;
    
    import flash.net.URLRequest;
    
    //扩展TiledMapServiceLayer图层实现加载google地图
    public class GoogleMapLayer extends TiledMapServiceLayer
    {
        private var _tileInfo:TileInfo=new TileInfo();
        private var _baseURL:String="";
        public var mapStyle:String=""; 
        
        public function GoogleMapLayer()
        {
            super();
            buildTileInfo();
            setLoaded(true);
        }
        
        override public function get fullExtent():Extent
        {
            return new Extent(-20037508.342787,-20037508.342787,20037508.342787,new SpatialReference(102113));
        }
        
        override public function get initialExtent():Extent
        {
            return new Extent(-20037508.342787,new SpatialReference(102113));
        }
        
        override public function get spatialReference():SpatialReference
        {
            return new SpatialReference(102113);
        }
        
        override public function get tileInfo():TileInfo
        {
            return _tileInfo;
        }
        
        //获取矢量地图
        override protected function getTileURL(level:Number,row:Number,col:Number):URLRequest
        {            
            var s:String = "Galileo".substring(0,((3 * x + y) % 8)); 
            var url:String; 
            
            //获取矢量地图             
            if(mapStyle == "Vector")                 
            {                 
                url = "http://mt"+(col%4)+".google.cn/vt/lyrs=m@158000000&hl=zh-CN&gl=cn&" +                     
                    "x=" + col + "&" +                     
                    "y=" + row + "&" +                 
                    "z=" + level+ "&" +                 
                    "s=" + s;                 
            }                 
                
            //获取地形图
            else if(mapStyle == "Terrain")                 
            {                 
                url = "http://mt"+(col%4)+".google.cn/vt/lyrs=t@128,r@177000000&hl=zh-CN&gl=cn&" +                     
                    "x=" + col + "&" +                     
                    "y=" + row + "&" +                     
                    "z=" + level+ "&" +                     
                    "s=" + s; 
            }
                
            //获取影像地图
            else if(mapStyle == "Image")                 
            {                 
                url = "http://mt"+(col%4)+".google.cn/vt/lyrs=s@101&hl=zh-CN&gl=cn&" +                     
                    "x=" + col + "&" +                     
                    "y=" + row + "&" +                     
                    "z=" + level+ "&" +                     
                    "s=" + s;                 
            } 
                
            //获取道路等POI，和影像地图配合使用     
            else if(mapStyle == "POI")            
            {                 
                url = "http://mt"+(col%4)+".google.cn/vt/imgtp=png32&lyrs=h@169000000&hl=zh-CN&gl=cn&" +                     
                    "x=" + col + "&" +                     
                    "y=" + row + "&" +                     
                    "z=" + level+ "&" +                     
                    "s=" + s;                 
            } 
            
            return new URLRequest(url);
        }
        
        private function buildTileInfo():void
        {
            _tileInfo.height=256;
            _tileInfo.width=256;
            _tileInfo.origin=new MapPoint(-20037508.342787,20037508.342787);
            _tileInfo.spatialReference=new SpatialReference(102113);
            _tileInfo.lods = [
                new LOD(0,156543.033928,591657527.591555),new LOD(1,78271.5169639999,295828763.795777),new LOD(2,39135.7584820001,147914381.897889),new LOD(3,19567.8792409999,73957190.948944),new LOD(4,9783.93962049996,36978595.474472),new LOD(5,4891.96981024998,18489297.737236),new LOD(6,2445.98490512499,9244648.868618),new LOD(7,1222.99245256249,4622324.434309),new LOD(8,611.49622628138,2311162.217155),new LOD(9,305.748113140558,1155581.108577),new LOD(10,152.874056570411,577790.554289),new LOD(11,76.4370282850732,288895.277144),new LOD(12,38.2185141425366,144447.638572),new LOD(13,19.1092570712683,72223.819286),new LOD(14,9.55462853563415,36111.909643),new LOD(15,4.77731426794937,18055.954822),new LOD(16,2.38865713397468,9027.977411),new LOD(17,1.19432856685505,4513.988705),new LOD(18,0.597164283559817,2256.994353),new LOD(19,0.298582141647617,1128.497176)
            ];
        }
    }
    
}

2. 在MapManager.mxml文件中引入GoogleMapLayer

import com.esri.viewer.GoogleMapLayer;

3. 在MapManager.mxml文件的添加对图类型的判断

在MapManager.mxml文件的addLayerToMap函数的"swicth...case"语句中添加以下代码：

case "googlemap":
                    {
                        var googleMapLayer:GoogleMapLayer=new GoogleMapLayer();
                        googleMapLayer.name=label;
                        if (style)
                        {
                            googleMapLayer.mapStyle= style;
                        }
                        googleMapLayer.id=label;
                        googleMapLayer.alpha=alpha;
                        googleMapLayer.visible=visible;
                        layerObject.layer=googleMapLayer;
                        googleMapLayer.addEventListener(LayerEvent.LOAD_ERROR,layer_loadErrorEvent);
                        googleMapLayer.addEventListener(LayerEvent.LOAD,layer_loadEvent);
                        map.addLayer(googleMapLayer);
                        break;
                    }

4. 在配置文件中添加googlemap底图

<basemaps>
           <layer label="GoogleMapLayer"  type="GoogleMap"  style="Terrain"   visible="true"/>
        </basemaps>