How to get a layer in the map using layer name?

GarryStewart

Hi, I'm working with the javascript 3.2 api, and have a map that loads from a pre-defined web map.   I'm now wanting to get a handle to a layer in the map using the layer name.  

I've managed to write some javacript code that locates the layerInfo for the said layer, but I have no idea how to get the actual layer from the map.

_getFeatureLayer: function(layerName) {     
var layer;
        
for (var j = 0, jl = this.map.layerIds.length; j < jl; j++)         
{             
   var currentLayerName = this.map.layerIds;             
   var currentLayer = this.map.getLayer(currentLayerName);               
   if (currentLayer.layerInfos.length > 0) 
   {                 
      layer = this._findSubLayerByName(currentLayer, layerName);                 
      if (layer != null) 
      {                     
         break;                 
      }             
   }         
}
return layer; 
},   

_findSubLayerByName: function (parentLayer, subLayerName) 
{     
   var layer;       
   for (var j = 0, jl = parentLayer.layerInfos.length; j < jl; j++)     
   {         
      var layerInfo = parentLayer.layerInfos;           
      if (layerInfo.name == subLayerName) 
      {             
         /* The correct layer is located, but how do I actually get the layer, this does not work. */
         var subLayerUrl = parentLayer.url + "/" + j;                          
         layer = new FeatureLayer(subLayerUrl); /* This doesn't give me the layer that is already added to the map */ 
         break;         
      }     
   }       
   return layer; 
}

rscheitlin

Garry,

   OK. Let me break in down for you then. When you add a url like https://gisserver.domain.com/secure/rest/services/MyCustomMap/MapServer to your web map that layer is added as a dynamic layer (ArcGISDynamicMapServiceLayer) which is just an image that is returned from ArcGIS Server. The client does not add individual sublayers to the map it just adds the image from the server to the map. So though you may see the sublayers shown in the map it is just an image.