Change sublayer renderer

<UserControl x:Name="_this"
             x:Class="ArcGIS.WinUI.Samples.ChangeSublayerRenderer.ChangeSublayerRenderer"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:esriUI="using:Esri.ArcGISRuntime.UI.Controls">
    <Grid>
        <esriUI:MapView x:Name="MyMapView" />
        <Border Style="{StaticResource BorderStyle}">
            <StackPanel>
                <TextBlock x:Name="ChangeSublayerRendererInstructionsLabel"
                           Margin="0,0,0,10"
                           FontWeight="SemiBold"
                           Text="Click 'change sublayer renderer' to apply a unique value renderer to the counties sub-layer."
                           TextWrapping="Wrap" />
                <Button x:Name="ChangeSublayerRendererButton"
                        HorizontalAlignment="Stretch"
                        Click="ChangeSublayerRendererButton_Click"
                        Content="Change sublayer renderer" />
            </StackPanel>
        </Border>
    </Grid>
</UserControl>

// Copyright 2018 Esri.
//
// Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License.
// You may obtain a copy of the License at: http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific
// language governing permissions and limitations under the License.

using Esri.ArcGISRuntime.Geometry;
using Esri.ArcGISRuntime.Mapping;
using Esri.ArcGISRuntime.Symbology;
using Microsoft.UI.Xaml;
using System.Collections.Generic;
using System.Drawing;

namespace ArcGIS.WinUI.Samples.ChangeSublayerRenderer
{
    [ArcGIS.Samples.Shared.Attributes.Sample(
        name: "Change sublayer renderer",
        category: "Layers",
        description: "Apply a renderer to a sublayer.",
        instructions: "Wait for the map image layer to load. Click the button to apply a unique value renderer to see different population ranges in the counties sub-layer data.",
        tags: new[] { "class breaks", "dynamic layer", "dynamic rendering", "renderer", "sublayer", "symbology", "visualization" })]
    public partial class ChangeSublayerRenderer
    {
        // ArcGIS map image layer that contains four Census sub-layers.
        private ArcGISMapImageLayer _arcGISMapImageLayer;

        public ChangeSublayerRenderer()
        {
            InitializeComponent();

            // Load the initial datasets in the map.
            Initialize();
        }

        private void Initialize()
        {
            // Create a new map based on the streets base map.
            Map newMap = new Map(BasemapStyle.ArcGISStreets);

            // Create an envelope that covers the continental US in the web Mercator spatial reference.
            Envelope continentalUSEnvelope = new Envelope(-14193469.5655232, 2509617.28647268, -7228772.04749191, 6737139.97573925, SpatialReferences.WebMercator);

            // Zoom the map to the extent of the envelope.
            newMap.InitialViewpoint = new Viewpoint(continentalUSEnvelope);

            // Assign the map to the MapView.
            MyMapView.Map = newMap;

            // Create an ArcGIS map image layer based on the Uri to that points to an ArcGIS Server map service that contains four Census sub-layers.
            // NOTE: sub-layer[0] = Census Block Points, sub-layer[1] = Census Block Group, sub-layer[3] = Counties, sub-layer[3] = States.
            _arcGISMapImageLayer = new ArcGISMapImageLayer(new System.Uri("https://sampleserver6.arcgisonline.com/arcgis/rest/services/Census/MapServer"));

            // Add the ArcGIS map image layer to the map's operation layers collection.
            newMap.OperationalLayers.Add(_arcGISMapImageLayer);
        }

        private ClassBreaksRenderer CreateClassBreaksRenderer()
        {
            // Define the colors that will be used by the unique value renderer.
            Color gray = Color.FromArgb(255, 153, 153, 153);
            Color blue1 = Color.FromArgb(255, 227, 235, 207);
            Color blue2 = Color.FromArgb(255, 150, 194, 191);
            Color blue3 = Color.FromArgb(255, 97, 166, 181);
            Color blue4 = Color.FromArgb(255, 69, 125, 150);
            Color blue5 = Color.FromArgb(255, 41, 84, 120);

            // Create a gray outline and five fill symbols with different shades of blue.
            SimpleLineSymbol outlineSimpleLineSymbol = new SimpleLineSymbol(SimpleLineSymbolStyle.Solid, gray, 1);
            SimpleFillSymbol simpleFileSymbol1 = new SimpleFillSymbol(SimpleFillSymbolStyle.Solid, blue1, outlineSimpleLineSymbol);
            SimpleFillSymbol simpleFileSymbol2 = new SimpleFillSymbol(SimpleFillSymbolStyle.Solid, blue2, outlineSimpleLineSymbol);
            SimpleFillSymbol simpleFileSymbol3 = new SimpleFillSymbol(SimpleFillSymbolStyle.Solid, blue3, outlineSimpleLineSymbol);
            SimpleFillSymbol simpleFileSymbol4 = new SimpleFillSymbol(SimpleFillSymbolStyle.Solid, blue4, outlineSimpleLineSymbol);
            SimpleFillSymbol simpleFileSymbol5 = new SimpleFillSymbol(SimpleFillSymbolStyle.Solid, blue5, outlineSimpleLineSymbol);

            // Create a list of five class breaks for different population ranges.
            List<ClassBreak> listClassBreaks = new List<ClassBreak>
            {
                new ClassBreak("-99 to 8560", "-99 to 8560", -99, 8560, simpleFileSymbol1),
                new ClassBreak("> 8,560 to 18,109", "> 8,560 to 18,109", 8560, 18109, simpleFileSymbol2),
                new ClassBreak("> 18,109 to 35,501", "> 18,109 to 35,501", 18109, 35501, simpleFileSymbol3),
                new ClassBreak("> 35,501 to 86,100", "> 35,501 to 86,100", 35501, 86100, simpleFileSymbol4),
                new ClassBreak("> 86,100 to 10,110,975", "> 86,100 to 10,110,975", 86100, 10110975, simpleFileSymbol5)
            };

            // Create and return the a class break renderer for use with the POP2007 field in the counties sub-layer.
            return new ClassBreaksRenderer("POP2007", listClassBreaks);
        }

        private void ChangeSublayerRendererButton_Click(object sender, RoutedEventArgs e)
        {
            // Get the counties sub-layer (the 3rd layer) from the ArcGIS map image layer.
            ArcGISMapImageSublayer countiesArcGISMapImageSubLayer = (ArcGISMapImageSublayer)_arcGISMapImageLayer.Sublayers[2];

            // Set the renderer of the ArcGIS map image sub-layer to a class break renderer based on population.
            countiesArcGISMapImageSubLayer.Renderer = CreateClassBreaksRenderer();

            // Disable the button after has been used.
            ChangeSublayerRendererButton.IsEnabled = false;
        }
    }
}