How do I symbolize a feature class in a map using ArcGIS Pro SDK button?

[JoshuaO_Neil]

Hello,

I have created an ArcGIS Pro button using ArcGIS Pro SDK to add a feature class to a map. My code is below. How would I add to this button to now symbolize that polygon feature class to have a black outline and yellow fill?

Here is what I have to add a feature class:

protected override void OnClick()
{
   if (MapView.Active?.Map == null) return;
   ArcGIS.Desktop.Framework.Threading.Tasks.QueuedTask.Run(() =>
   {
      using (Geodatabase geodatabase = new Geodatabase(new FileGeodatabaseConnectionPath(new       Uri(@"L:\data\ESRI_10_6\usa\census\states.gdb"))))
      {
         using (FeatureClass addFeatureClass = geodatabase.OpenDataset<FeatureClass>("states"))
         {
            LayerFactory.Instance.CreateFeatureLayer(addFeatureClass, MapView.Active.Map, 0, "states");
         }
      }
});

How do I now add to this button code to now symbolize as a black outline and yellow fill? How do I reference the above feature class that I just added to the map? I can't seem to figure out how to do this. Your help would be much appreciated.

Thank you!

[UmaHarano]

Hi Joshua

Here is the code for a Simple renderer that could help: Simple Renderer for a Polygon feature layer.

internal static Task SimpleRendererPolygon(FeatureLayer featureLayer)
{            
    return QueuedTask.Run(() =>
    {
        //Creating a polygon with a red fill and blue outline.
        CIMStroke outline = SymbolFactory.Instance.ConstructStroke(
             ColorFactory.Instance.BlueRGB, 2.0, SimpleLineStyle.Solid);
        CIMPolygonSymbol fillWithOutline = SymbolFactory.Instance.ConstructPolygonSymbol(
             ColorFactory.Instance.CreateRGBColor(255, 190, 190), SimpleFillStyle.Solid, outline);
        //Get the layer's current renderer
        CIMSimpleRenderer renderer = featureLayer.GetRenderer() as CIMSimpleRenderer;

        //Update the symbol of the current simple renderer
        renderer.Symbol = fillWithOutline.MakeSymbolReference();

        //Update the feature layer renderer
        featureLayer.SetRenderer(renderer);
    });
}‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

Using this code snippet above, here is how the polygon feature will get renderered -

[JoshuaO_Neil]

Thank you, how do I use that for my feature class that I am using? Do I need to add more code to do so? Or do I just add it below my add feature class code?

Your help is much appreciated.

[JoshuaO_Neil]

For example, I am getting an error "feature layer does not exist in the current context". How do I tell it that I want to apply this symbology to a certain feature class, such as the one that I just added?

[UmaHarano]

Hi

You can get your feature layer like this:

//Gets the first layer in the active map
var lyr = MapView.Active.Map.GetLayersAsFlattenedList().OfType<FeatureLayer>().First();

//Or

//Gets layer with a specific name
 var lyr = MapView.Active.Map.GetLayersAsFlattenedList().OfType<FeatureLayer>().Where(l => l.Name == "U.S. States (Generalized)").First(); ;‍‍‍‍‍‍‍‍‍‍‍‍

To give you an idea how you could use these code snippets, given below is the entire workflow. If you have a button, you can do the following in your button's OnClick method:

 protected override async void OnClick()
        {
            //Gets your feature layer            
            var lyr = MapView.Active.Map.GetLayersAsFlattenedList().OfType<FeatureLayer>().First();
            await SimpleRendererPolygon(lyr); //calls the method below to apply the simple renderer
        }

 internal static Task SimpleRendererPolygon(FeatureLayer featureLayer)
        {
            return QueuedTask.Run(() =>
            {                
                //Creating a polygon with a red fill and blue outline.
                CIMStroke outline = SymbolFactory.Instance.ConstructStroke(
                     ColorFactory.Instance.BlueRGB, 2.0, SimpleLineStyle.Solid);
                CIMPolygonSymbol fillWithOutline = SymbolFactory.Instance.ConstructPolygonSymbol(
                     ColorFactory.Instance.CreateRGBColor(255, 190, 190), SimpleFillStyle.Solid, outline);
                //Get the layer's current renderer
                CIMSimpleRenderer renderer = featureLayer.GetRenderer() as CIMSimpleRenderer;

                //Update the symbol of the current simple renderer
                renderer.Symbol = fillWithOutline.MakeSymbolReference();

                //Update the feature layer renderer
                featureLayer.SetRenderer(renderer);
            });
        }‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

[JoshuaO_Neil]

This is exactly what I was looking to do. Thank you so much for the detailed response!