How to parse only Operational Layers from Web Map

AaronConnolly

In the Document's GetMapCompleted event is it possible to get a list of the operational layers from the base map, rather than have to parse the DocumentValues property? The DocumentValues property seems to really only be a CLR object representation of the JSON that makes up the WebMap. I don't think it is.

What I want to do is this:

void _webMap_GetMapCompleted(object sender, GetMapCompletedEventArgs e)
{
    List<Layer> operationalLayers = e.OperationalLayers;

    // Do something with those layers ... 
}

Our objective is to parse the web map for everything EXCEPT the basemap and add that to an existing map. Unfortunately I'm not sure that it's reliable to do that because there could be web maps whose basemap is pertinent.

Using the map like this is not reliable either because you only know what type of layer you have, not it's intended purpose (base or operational):

foreach(Layer layer in e.Map.Layers)
{
    // Is layer operational or base map?
    // No way to know?
}

As a last resort we could parse the DocumentValues property for a list of layer IDs for those in the operationalLayers List, then parse those out of the e.Map.Layers list. Again, this might not be reliable.

Thanks,
- Aaron

DominiqueBroux

Can you instantiate web map from a portal item whose type is "feature service"? I'm trying to create a web map asynchronously from an ArcGISPortalItem that is simply a layer of type "feature service" and when I call WebMap.FromPortalItemAsync(...);

No, unfortunately, for now, the creation of a webmap from a portal item works only if the item is of type WebMap.

To create a webmap from a portal item of type 'feature service', you have to instantiate the webmap by code (sample), instantiate a webmaplayer, set the Url, Id and ItemId properties of the webmaplayer, add the webmaplayer to the webmap.OperationalLayers and create the map from the webmap using Document.GetMapAsync(webMap)