调用地图服务问题
以下为加载几种类型地图服务的flex源码：
case "wmts":
{
var wmtsLayer:GeoTileLayer = new GeoTileLayer(url);
wmtsLayer.alpha = alpha;
wmtsLayer.id = layId;
wmtsLayer.name = label;
wmtsLayer.visible = visible;
layerObject.layer = wmtsLayer;
map.addLayer(wmtsLayer);
break;
}
case "czwmts":
{
var array:Array=new Array();
array=url.split(';');
var tlayer:TLayer=new TLayer();
tlayer.id="baseMap";
tlayer.name="地图";
tlayer.visible=true;
tlayer.layerId="vec";
tlayer.serviceMode="KVP";
tlayer.tileMatrixSetId="c";
tlayer.imageFormat="tiles";
tlayer.baseURL=array[0];
map.addLayer(tlayer);
var tlayerr:TLayer=new TLayer();
tlayerr.id="tipMap";
tlayerr.name="切片地图";
tlayerr.visible=true;
tlayerr.layerId="cva";
tlayerr.serviceMode="KVP";
tlayerr.tileMatrixSetId="c";
tlayerr.imageFormat="tiles";
tlayerr.baseURL=array[1];
map.addLayer(tlayerr);
break;
}
case "tiled":
{
var tiledLayer:ArcGISTiledMapServiceLayer = new ArcGISTiledMapServiceLayer(url);
tiledLayer.alpha = alpha;
tiledLayer.id = layId;
tiledLayer.name = label;
tiledLayer.token = token;
tiledLayer.visible = visible;
if (displayLevels)
{
tiledLayer.displayLevels = displayLevels.split(",");
for (i = 0; i < tiledLayer.displayLevels.length; i++)
{
tiledLayer.displayLevels[i] = Number(tiledLayer.displayLevels[i]); // convert to Numbers
}
}
if (proxyUrl && useProxy)
{
tiledLayer.proxyURL = proxyUrl;
}
layerObject.layer = tiledLayer;
map.addLayer(tiledLayer);
break;
}
case "dynamic":
{
var dynLayer:ArcGISDynamicMapServiceLayer = new ArcGISDynamicMapServiceLayer(url);
dynLayer.alpha = alpha;
dynLayer.id = layId;
dynLayer.name = label;
dynLayer.imageFormat = "png32";
dynLayer.token = token;
dynLayer.visible = visible;
dynLayer.useMapTime = useMapTime;
if (autoRefresh > 0)
{
setInterval(dynLayer.refresh, autoRefresh * 1000);
}
if (imageFormat)
{
dynLayer.imageFormat = imageFormat;
}
if (visibleLayers)
{
var vizLayers:Array = visibleLayers.split(",");
for (i = 0; i < vizLayers.length; i++)
{
vizLayers[i] = Number(vizLayers[i]); // convert to Numbers
}
dynLayer.visibleLayers = new ArrayCollection(vizLayers);
}
if (proxyUrl && useProxy)
{
dynLayer.proxyURL = proxyUrl;
}
layerObject.layer = dynLayer;
map.addLayer(dynLayer);
break;
}
case "feature":
{
var featureLayer:FeatureLayer = new FeatureLayer(url);
featureLayer.addEventListener(GraphicEvent.GRAPHIC_ADD,fLayer_graphicAddHandler);
featureLayer.addEventListener(FlexEvent.HIDE, featureLayer_hideHandler);
featureLayer.alpha = alpha;
featureLayer.id = layId;
featureLayer.name = label;
featureLayer.outFields = [ '*' ]; // TODO: be smarter
featureLayer.token = token;
featureLayer.visible = visible;
featureLayer.useMapTime = useMapTime;
if (useAMF)
{
featureLayer.useAMF = (useAMF == "true");
}
if (mode)
{
featureLayer.mode = mode;
}
if (definitionExpression)
{
featureLayer.definitionExpression = definitionExpression;
}
if (proxyUrl && useProxy)
{
featureLayer.proxyURL = proxyUrl;
}
layerObject.layer = featureLayer;
map.addLayer(featureLayer);
break;
}
case "bing":
{
var veTiledLayer:VETiledLayer = new VETiledLayer();
veTiledLayer.id = layId;
veTiledLayer.name = label;
veTiledLayer.key = bingMapKey;
veTiledLayer.visible = visible;
veTiledLayer.alpha = alpha;
if (style)
{
veTiledLayer.mapStyle = style;
}
if (culture)
{
veTiledLayer.culture = culture;
}
if (displayLevels)
{
veTiledLayer.displayLevels = displayLevels.split(",");
for (i = 0; i < veTiledLayer.displayLevels.length; i++)
{
veTiledLayer.displayLevels[i] = Number(veTiledLayer.displayLevels[i]); // convert to Numbers
}
}
layerObject.layer = veTiledLayer;
map.addLayer(veTiledLayer);
break;
}
case "image":
{
var imgLayer:ArcGISImageServiceLayer = new ArcGISImageServiceLayer(url);
imgLayer.id = layId;
imgLayer.name = label;
imgLayer.alpha = alpha;
imgLayer.token = token;
imgLayer.visible = visible;
imgLayer.noData = noData;
imgLayer.useMapTime = useMapTime;
if (imageFormat)
{
imgLayer.imageFormat = imageFormat;
}
if (bandIds)
{
imgLayer.bandIds = bandIds.split(",");
for (i = 0; i < imgLayer.bandIds.length; i++)
{
imgLayer.bandIds[i] = Number(imgLayer.bandIds[i]); // convert to Numbers
}
}
if (proxyUrl && useProxy)
{
imgLayer.proxyURL = proxyUrl;
}
layerObject.layer = imgLayer;
map.addLayer(imgLayer);
break;
}
case "arcims":
{
var arcimsLayer:ArcIMSMapServiceLayer = new ArcIMSMapServiceLayer();
arcimsLayer.alpha = alpha;
arcimsLayer.id = layId;
arcimsLayer.name = label;
arcimsLayer.visible = visible;
arcimsLayer.serviceHost = serviceHost;
arcimsLayer.serviceName = serviceName;
if (autoRefresh > 0)
{
setInterval(arcimsLayer.refresh, autoRefresh * 1000);
}
if (imageFormat)
{
arcimsLayer.imageFormat = imageFormat;
}
if (visibleLayers)
{
var visLayers:Array = visibleLayers.split(",");
arcimsLayer.visibleLayers = new ArrayCollection(visLayers);
}
if (proxyUrl && useProxy)
{
arcimsLayer.proxyURL = proxyUrl;
}
if (username && password)
{
arcimsLayer.username = username;
arcimsLayer.password = password;
}
layerObject.layer = arcimsLayer;
map.addLayer(arcimsLayer);
break;
}
case "wms":
{
var wmsLayer:WMSLayer = new WMSLayer(url);
wmsLayer.alpha = alpha;
wmsLayer.id = layId;
wmsLayer.name = label;
wmsLayer.visible = visible;
if (wkid)
{
wmsLayer.spatialReference = new SpatialReference(wkid);
}
if (autoRefresh > 0)
{
setInterval(wmsLayer.refresh, autoRefresh * 1000);
}
if (imageFormat)
{
wmsLayer.imageFormat = imageFormat;
}
if (visibleLayers)
{
var wmsVisLayers:Array = visibleLayers.split(",");
wmsLayer.visibleLayers = new ArrayList(wmsVisLayers);
}
if (proxyUrl && useProxy)
{
wmsLayer.proxyURL = proxyUrl;
}
if (skipGetCapabilities)
{
wmsLayer.skipGetCapabilities = skipGetCapabilities == "true";
}
if (username && password)
{
wmsLayer.username = username;
wmsLayer.password = password;
}
if (version)
{
wmsLayer.version = version;
}
layerObject.layer = wmsLayer;
map.addLayer(wmsLayer);
break;
}
case "osm":
{
var osmLayer:OpenStreetMapLayer = new OpenStreetMapLayer();
osmLayer.alpha = alpha;
osmLayer.id = layId;
osmLayer.name = label;
osmLayer.visible = visible;
layerObject.layer = osmLayer;
map.addLayer(osmLayer);
break;
}
default:
{
Alert.show(StringUtil.substitute(getDefaultString('incorrectLayerTypeText'), "'" + type + "'"));
break;
}
这样写虽然方便，但会带来一个严重的问题：
我们在初始化地图服务，加载地图图层的时候，在地图图层还没有完全加载完成的时候，就把地图服务加到地图上了，这样很可能导致地图图层加载失败的问题了。整体来说，如果是访问外网的地图服务时，网速和浏览器很大程度上会影响地图服务的加载时间，也会很容易导致这样的问题，这里，把这个问题提出来，希望和大家一起研究更好的解决方案。