topic Re: Adding Graphic.Attributes in XAML in ArcGIS API for Silverlight Questions

Adding Graphic.Attributes in XAML

DanielWalton — Thu, 11 Nov 2010 15:22:48 GMT

I'm trying to add graphics to my map in XAML using this syntax:

[HTML]<esri:GraphicsLayer ID="Shapes">
       <esri:Graphic>
          <esri:Graphic.Attributes>
             <sys:String x:Key="Name">Graphic 0</sys:String>
          </esri:Graphic.Attributes>
          <esri:Graphic.Geometry>....</esri:Graphic.Geometry>
       </esri:Graphic>
</esri:GraphicsLayer>[/HTML]I get a runtime exception (I assume because Attributes is read-only). Is there a way to add attributes with XAML?

Re: Adding Graphic.Attributes in XAML

JenniferNery — Sun, 12 Dec 2021 06:31:28 GMT

If you are using SL4, the only way I could think of about doing this is as follows:

   <TextBox  Width="50"  Text="{Binding [STATE_NAME], Mode=TwoWay}" DataContext="{Binding ElementName=MyMap, Path=Layers[MyGraphics].Graphics[0].Attributes}"/>

Where MyMap is the name of my map, MyGraphics is the ID of my Layer, and Graphics[0] is expected to exist.

This is the sample, I placed breakpoint on MouseLeftButtonDown to inspect the Attributes. You can also do a MessageBox.Show() on e.Graphic.Attributes["STATE"] to see that it matches your TextBox. It's not a pretty solution because each TextBox would have to represent a field for one of the graphics.

 <Grid x:Name="LayoutRoot" Background="White">

  <Grid.Resources>
   <esri:SimpleMarkerSymbol x:Key="RedMarkerSymbol" Color="Red" Size="12" Style="Circle" />
  </Grid.Resources>

  <esri:Map x:Name="MyMap" Background="White">
   <esri:ArcGISTiledMapServiceLayer ID="PhysicalTiledLayer" Url="http://services.arcgisonline.com/ArcGIS/rest/services/NPS_Physical_World_2D/MapServer"/>

   <esri:GraphicsLayer ID="MyGraphics" MouseLeftButtonDown="GraphicsLayer_MouseLeftButtonDown">
    <esri:GraphicsLayer.Graphics >

     <esri:Graphic Symbol="{StaticResource RedMarkerSymbol}" >
      <esri:MapPoint X="-140.9" Y="63.391" />      
     </esri:Graphic>
    </esri:GraphicsLayer.Graphics>
   </esri:GraphicsLayer>
  </esri:Map>
  <StackPanel VerticalAlignment="Top" HorizontalAlignment="Center" >
   <TextBox  Width="50"  Text="{Binding [STATE_NAME], Mode=TwoWay}" DataContext="{Binding ElementName=MyMap, Path=Layers[MyGraphics].Graphics[0].Attributes}"/>
  </StackPanel>
 
 </Grid>

Re: Adding Graphic.Attributes in XAML

DanielWalton — Thu, 11 Nov 2010 17:42:00 GMT

My goal is to 'hard-code' some features with attributes into my app. I am generating the XAML dynamically from a FeatureService dataset, then when (if) I can get it working, I will remove the FeatureService and just have the graphics. If I can't add the attributes with XAML, is there a way to store JSON messages and trick the FeatureService into reading them when it loads?

Re: Adding Graphic.Attributes in XAML

JenniferNery — Thu, 11 Nov 2010 18:15:39 GMT

You don't want to update the attributes in code-behind? (i.e. graphic.Attributes["STATE"] = "California")

Re: Adding Graphic.Attributes in XAML

DanielWalton — Thu, 11 Nov 2010 18:18:40 GMT

No, this is just a one-off operation to capture the geometry and attributes of a certain set of features, then hard-code both into my app.

Re: Adding Graphic.Attributes in XAML

JenniferNery — Sun, 12 Dec 2021 06:31:31 GMT

I dont know if this would solve your problem but what you can do is query the FeatureService and in the QueryTask_ExecuteCompleted update a GraphicsCollection (In the sample-code below, use the same instance as MyGraphicCollection).

 <Grid.Resources>
  <esri:GraphicCollection x:Key="MyGraphicCollection"/>
<!--more code goes here -->
 </Grid.Resources>
<!--more code goes here -->
 <esri:GraphicsLayer ID="MyGraphicsLayer" 
   Graphics="{Binding Source={StaticResource MyGraphicCollection}, Path=Graphics}" Renderer="{StaticResource MyRenderer}"/>

Re: Adding Graphic.Attributes in XAML

DanielWalton — Thu, 11 Nov 2010 18:54:09 GMT

I'm trying to get away from querying a service and load stuff fast.

Re: Adding Graphic.Attributes in XAML

DominiqueBroux — Thu, 11 Nov 2010 20:10:53 GMT

One possible option is you to use an XML format to store graphics.
You will find sample code to serialize/deserialize graphics here: http://forums.arcgis.com/threads/8774-save-layer-to-xml-file

Re: Adding Graphic.Attributes in XAML

DanielWalton — Fri, 12 Nov 2010 15:59:14 GMT

Perfect. Thanks Dominique!