public class CIMUniqueValueClass : CIMObject, System.ComponentModel.INotifyPropertyChanged, System.Xml.Serialization.IXmlSerializable  

{
        //The goal is to construct the CIMUniqueValueRenderer which will be applied to the feature layer.
        // To do this, the following are the objects we need to set the renderer up with the fields and symbols.
        // As a reference, this is the USCities dataset. Snippet will create a unique value renderer that applies 
        // specific symbols to all the cities in California and Alabama.  The rest of the cities will use a default symbol.

        // First create a "CIMUniqueValueClass" for the cities in Alabama.
        List<CIMUniqueValue> listUniqueValuesAlabama = new List<CIMUniqueValue> { new CIMUniqueValue { FieldValues = new string[] { "Alabama" } } };
        CIMUniqueValueClass alabamaUniqueValueClass = new CIMUniqueValueClass
        {
            Editable = true,
            Label = "Alabama",
            Patch = PatchShape.Default,
            Symbol = SymbolFactory.Instance.ConstructPointSymbol(ColorFactory.Instance.RedRGB).MakeSymbolReference(),
            Visible = true,
            Values = listUniqueValuesAlabama.ToArray()
        };
        // Create a "CIMUniqueValueClass" for the cities in California.
        List<CIMUniqueValue> listUniqueValuescalifornia = new List<CIMUniqueValue> { new CIMUniqueValue { FieldValues = new string[] { "California" } } };
        CIMUniqueValueClass californiaUniqueValueClass = new CIMUniqueValueClass
        {
            Editable = true,
            Label = "California",
            Patch = PatchShape.Default,
            Symbol = SymbolFactory.Instance.ConstructPointSymbol(ColorFactory.Instance.BlueRGB).MakeSymbolReference(),
            Visible = true,
            Values = listUniqueValuescalifornia.ToArray()
        };
        //Create a list of the above two CIMUniqueValueClasses
        List<CIMUniqueValueClass> listUniqueValueClasses = new List<CIMUniqueValueClass>
{
              alabamaUniqueValueClass, californiaUniqueValueClass
};
        //Create a list of CIMUniqueValueGroup
        CIMUniqueValueGroup uvg = new CIMUniqueValueGroup
        {
            Classes = listUniqueValueClasses.ToArray(),
        };
        List<CIMUniqueValueGroup> listUniqueValueGroups = new List<CIMUniqueValueGroup> { uvg };
        //Create the CIMUniqueValueRenderer
        CIMUniqueValueRenderer uvr = new CIMUniqueValueRenderer
        {
            UseDefaultSymbol = true,
            DefaultLabel = "all other values",
            DefaultSymbol = SymbolFactory.Instance.ConstructPointSymbol(ColorFactory.Instance.GreyRGB).MakeSymbolReference(),
            Groups = listUniqueValueGroups.ToArray(),
            Fields = new string[] { "STATE_NAME" }
        };
        //Set the feature layer's renderer.
        //Note: Run within a QueuedTask
        featureLayer.SetRenderer(uvr);
    }

{
  // Note: call within QueuedTask.Run()
  {
    var url = @"https://geoeventsample1.esri.com:6443/arcgis/rest/services/AirportTraffics/StreamServer";
    var uri = new Uri(url, UriKind.Absolute);

    var createParams = new FeatureLayerCreationParams(uri)
    {
      IsVisible = false
    };
    streamLayer = LayerFactory.Instance.CreateLayer<StreamLayer>(
                        createParams, map);
    //Define the unique values by hand
    var uvr = new CIMUniqueValueRenderer()
    {
      Fields = new string[] { "ACTYPE" },
      UseDefaultSymbol = true,
      DefaultLabel = "Others",
      DefaultSymbol = SymbolFactory.Instance.ConstructPointSymbol(
                  CIMColor.CreateRGBColor(185, 185, 185), 8, SimpleMarkerStyle.Hexagon).MakeSymbolReference()
    };

    var classes = new List<CIMUniqueValueClass>
    {
      //add in classes - one for ACTYPE of 727, one for DC 9
      new CIMUniqueValueClass()
      {
        Values = new CIMUniqueValue[] {
                new CIMUniqueValue() { FieldValues = new string[] { "B727" } } },
        Visible = true,
        Label = "Boeing 727",
        Symbol = SymbolFactory.Instance.ConstructPointSymbol(
                  ColorFactory.Instance.RedRGB, 10, SimpleMarkerStyle.Hexagon).MakeSymbolReference()
      },
      new CIMUniqueValueClass()
      {
        Values = new CIMUniqueValue[] {
                new CIMUniqueValue() { FieldValues = new string[] { "DC9" } } },
        Visible = true,
        Label = "DC 9",
        Symbol = SymbolFactory.Instance.ConstructPointSymbol(
                  ColorFactory.Instance.GreenRGB, 10, SimpleMarkerStyle.Hexagon).MakeSymbolReference()
      }
    };
    //add the classes to a group
    var groups = new List<CIMUniqueValueGroup>()
  {
    new CIMUniqueValueGroup() {
       Classes = classes.ToArray()
    }
  };
    //add the groups to the renderer
    uvr.Groups = groups.ToArray();
    //Apply the renderer (for current observations)
    streamLayer.SetRenderer(uvr);
    streamLayer.SetVisibility(true);//turn on the layer        
  }
}

{
  // Note: call within QueuedTask.Run()
  {
    //Define the classes by hand to avoid using CreateRenderer(...)
    CIMUniqueValueClass uvcB727 = new CIMUniqueValueClass()
    {
      Values = new CIMUniqueValue[] { new CIMUniqueValue() { FieldValues = new string[] { "B727" } } },
      Visible = true,
      Label = "Boeing 727",
      Symbol = SymbolFactory.Instance.ConstructPointSymbol(CIMColor.CreateRGBColor(255, 0, 0), 8, SimpleMarkerStyle.Hexagon).MakeSymbolReference()
    };

    CIMUniqueValueClass uvcD9 = new CIMUniqueValueClass()
    {
      Values = new CIMUniqueValue[] { new CIMUniqueValue() { FieldValues = new string[] { "DC9" } } },
      Visible = true,
      Label = "DC 9",
      Symbol = SymbolFactory.Instance.ConstructPointSymbol(CIMColor.CreateRGBColor(0, 255, 0), 8, SimpleMarkerStyle.Hexagon).MakeSymbolReference()
    };
    //Assign the classes to a group
    CIMUniqueValueGroup uvGrp = new CIMUniqueValueGroup()
    {
      Classes = new CIMUniqueValueClass[] { uvcB727, uvcD9 }
    };
    //assign the group to the renderer
    var UVrndr = new CIMUniqueValueRenderer()
    {
      Fields = new string[] { "ACTYPE" },
      Groups = new CIMUniqueValueGroup[] { uvGrp },
      UseDefaultSymbol = true,
      DefaultLabel = "Others",
      DefaultSymbol = SymbolFactory.Instance.ConstructPointSymbol(
        CIMColor.CreateRGBColor(185, 185, 185), 8, SimpleMarkerStyle.Hexagon).MakeSymbolReference()
    };
    //set the renderer. Depending on the current events received, the
    //layer may or may not have events for each of the specified
    //unique value classes
    streamLayer.SetRenderer(UVrndr);
  }
}