The MessageLayer displays graphics with military symbols from one of the supported symbol dictionary types. Each message, represented by an instance of the Message class, comprises a Dictionary of System.String key value pairs. These specify a number of important characteristics of the message. For more information see Message. The key value pairs can be explicitly constructed or alternatively the MessageHelper class contains methods and properties to support the creation of messages, such as MessageHelper.CreateMilitaryUpdateMessage, MessageHelper.CreateMilitarySelectMessage, and MessageHelper.CreateMilitaryRemoveMessage. Once the message has been constructed the ProcessMessage method must be called. This will construct the symbol based on the provided symbol ID code ("sic") and the control points, then add the message the appropriate MessageSubLayer based on the MessageTypes. The reason that messages must be processed rather than simply being added to a ESRI.ArcGIS.Client.GraphicsLayer directly is that the geometry required to display the symbol (the control points) does not necessarily correlate to the geometry of the feature itself and is not limited to the standard point, polyline and polygon types, although these do cover approximately 95% of cases.

There may be up to three MessageSubLayers depending on the type of messages created. The supported message types are:

• "position_report"
• "spot_report"
• "chemlight"

System.Object
   System.Windows.Threading.DispatcherObject
      System.Windows.DependencyObject
         ESRI.ArcGIS.Client.Layer
            ESRI.ArcGIS.Client.AdvancedSymbology.MessageLayer

Target Platforms: Windows XP Professional, Windows Server 2003 family, Windows Vista, Windows Server 2008 family, Windows 7, Windows 8

Reference