Android Arcgis(15)、网络图层加载一

一、首先我们来看一个网络图层：

http://services.arcgisonline.com/arcgis/rest/services/World_Street_Map/MapServer，这是全球街道图。加载的代码也很简单：

private static final String WORLD_STREETS_URL = "http://services.arcgisonline.com/ArcGIS/rest/services/World_Street_Map/MapServer"; private MapView mMapView = null; private ArcGISTiledMapServiceLayer mWorldStreetsLayer = null; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); mMapView = (MapView) findViewById(R.id.map_view); mWorldStreetsLayer = new ArcGISTiledMapServiceLayer(WORLD_STREETS_URL); mMapView.addLayer(mWorldStreetsLayer); mWorldStreetsLayer.setOnStatusChangedListener(new OnStatusChangedListener() { @Override public void onStatusChanged(Object o, STATUS status) { if (status==STATUS.INITIALIZED){ Log.i("huang","加载成功"); }else if(status==STATUS.INITIALIZATION_FAILED||status==STATUS.LAYER_LOADING_FAILED){ Log.i("huang","加载失败"); } } }); }

效果图

问：为什么用ArcGISTiledMapServiceLayer 加载而不用其他图层加载呢？

用浏览器打开 http://services.arcgisonline.com/arcgis/rest/services/World_Street_Map/MapServer，可以看到详细信息。 它的子图层只有一个： 下面是坐标信息，注意Single Fused Map Cache: true，支持缓存。 与Tile Info信息，

通过信息说明这是一个TiledLayer,而ArcGISTiledMapServiceLayer是TiledLayer子类的子类，看一下ArcGISTiledMapServiceLayer的介绍 。

点开World Street Map链接， http://services.arcgisonline.com/arcgis/rest/services/World_Street_Map/MapServer/0，这是它的唯一子图层。真正加载的也是这个图层 Type虽然说是FeatureLayer，但它得用ArcGISFeatureLayer加载。

ArcGISFeatureLayer arcGISFeatureLayer = new ArcGISFeatureLayer(WORLD_STREETS_URL+"/0", ArcGISFeatureLayer.MODE.ONDEMAND); SimpleFillSymbol simpleFillSymbol = new SimpleFillSymbol(Color.argb(0,0,0,0),SimpleFillSymbol.STYLE.SOLID); mMapView.addLayer(arcGISFeatureLayer); arcGISFeatureLayer.setRenderer(new SimpleRenderer(simpleFillSymbol)); arcGISFeatureLayer.setOnStatusChangedListener(new OnStatusChangedListener() { @Override public void onStatusChanged(Object o, STATUS status) { if (status==STATUS.INITIALIZED){ Log.i("huang","加载成功"); }else if(status==STATUS.INITIALIZATION_FAILED||status==STATUS.LAYER_LOADING_FAILED){ Log.i("huang","加载失败"); } } });

上面虽然加载成功，但并看不到图层，而且报错：

FeatureSetCallback.onError com.esri.core.io.EsriServiceException: Requested operation is not supported by this service. The requested capability is not supported.

仔细再看网络信息， 大体上知道为什么报 The requested capability is not supported。也就是不能用这种方法加载，而得用前面的代码加载！！！