How to add a control at runtime

[CharlotteCrawford]

Hi there,

How would I go about adding a control, e.g stackpanel with a textblock in it to the map at runtime in a specific place? The effect I am wanting to achieve is similar to the silverlight control at this url -
http://maps.marlborough.govt.nz/FloodWatch/.  As you can see this control has blue labels at various places on the map. I'd like to do something similar, but don't quite know how to get started.


Thanks
CC

[HugoCardenas]

First, you should add your parent control (StackPanel) at design time using XAML.  Place it, anywhere on the map area and hide it, and add the textblock control as well.

<StackPanel x:Name="MyPanel" Visibility="Collapsed" ...>
   <TextBlock x:Name="MyTextblock" Text=""  />
</StackPanel>

Next, add whatever text you want to add to your textblock at run-time from code-behind; once you are done adding the text, you can set Visibility=Visibility.Visible to the StackPanel.

MyTextblock.Text = "The text to display";
MyPanel.Visibility = Visibility.Visible;

This would be the simplest way to do it.

I hope this helps!
Hugo.

[CharlotteCrawford]

Thanks for the help. It does get me a bit further.  I need to be able to add multiple instances of the control at runtime.   How can I do that?

I also want to position the controls near certain items in my graphics layer.  How do I relate the position of the control to something in a graphics layer?

[JenniferNery]

You can probably use GraphicsLayer with custom symbol that gets a value from the graphic.Attributes.

For example you can update this sample: http://help.arcgis.com/en/webapi/silverlight/samples/start.htm#FeatureLayerSimple to include the following code:

<esri:SimpleRenderer x:Key="MyRenderer">
    <esri:MarkerSymbol OffsetX="10" OffsetY="10">
     <esri:MarkerSymbol.ControlTemplate>
      <ControlTemplate>
       <StackPanel>        
        <TextBlock Text="{Binding Attributes[CITY_NAME]}" />
       </StackPanel>
      </ControlTemplate>
     </esri:MarkerSymbol.ControlTemplate>
    </esri:MarkerSymbol>
   </esri:SimpleRenderer>
<!--more code goes here-->
<esri:GraphicsLayer ID="MyGraphicsLayer" Renderer="{StaticResource MyRenderer}"/>

private void FeatureLayer_UpdateCompleted(object sender, EventArgs e)
{
 var source = sender as FeatureLayer;
 var target = MyMap.Layers["MyGraphicsLayer"] as GraphicsLayer;
 foreach (var g in source.Graphics)
 {
  var graphic = new Graphic() { Geometry = g.Geometry };
  foreach (var attribute in g.Attributes)
   graphic.Attributes[attribute.Key] = attribute.Value;
  target.Graphics.Add(graphic);
 }
}

[CharlotteCrawford]

Thanks Jennifer,  that looks like a good way to do it.  I always learn such good techniques from your posts, so keep up the good work!

CC