problem to show layers in legend using arcgis silverlight api

Question

I tried to create a simple webgis with silverlight. Software that I used to make the application: ArcGIS Desktop 10 (without sp), ArcGIS Server 10, Silverlight 4, Microsoft blend 4, and Visual Studio 2010 sp1. We generally use the code below to add layers to map:

<esri:Map x:Name="Map" >
        <esri:Map.Layers>
              <esri:ArcGISDynamicMapServiceLayer ID="samplewebgis" 
                    Url="http://m-pc/arcgis/rest/services/test/MapServer" />        
        </esri:Map.Layers>
  </esri:Map>

But when i use the code, the map legend shows no layers. then I tried the code below:

<esri:Map x:Name="Map"   Grid.RowSpan="3">                                  

      <esri:FeatureLayer  ID="xx" Url="http://m-pc/arcgis/rest/services/test/MapServer/0"/> 
      <esri:FeatureLayer  ID="yy" Url="http://m-pc/arcgis/rest/services/test/MapServer/1" /> 

</esri:Map>

This code works properly and legend show layers. Why can't I use esri:map.layers and why can't the legend show layers of map when I use map.layers?

Answer 1

Map.Layers refers to the layer collection in the application's code-behind. You don't need the esri:Map.Layers in your xaml code, because it understands that any child item in the esri:Map xml code will be a layer of some kind of layer.

If you want to manage layers in the code-behind, however, you would use Map.Layers.

XAML:

<esri:Map x:Name="Map" >
    <esri:ArcGISDynamicMapServiceLayer ID="samplewebgis" 
          Url="http://m-pc/arcgis/rest/services/test/MapServer" />        
</esri:Map>

Code-behind (VB.net)

Dim myLayer as New ArcGISDynamicMapServiceLayer("http://m-pc/arcgis/rest/services/test2/MapServer")
myLayer.ID = "samplewebgis_2"
Map.Layers.Add(myLayer)

Answer 2

The first sample is not an ArcGISDynamicMapServiceLayer. It is a tiled map service. Try using <esri:ArcGISTiledMapServiceLayer ...

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