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V25.1
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    HeatmapDataSourceAdapter Class

    The data adapter that provides data used to generate heatmap items.

    Namespace: DevExpress.XtraMap

    Assembly: DevExpress.XtraMap.v25.1.dll

    NuGet Package: DevExpress.Win.Map

    #Declaration

    public class HeatmapDataSourceAdapter :
        IHeatmapPointSource,
        IMapDataSourceAdapter

    #Example

    This example shows how to create a heatmap layer for the Map Control.

    image

    using DevExpress.XtraMap;
    using System;
    using System.Data;
    using System.Drawing;
    using System.Windows.Forms;
    
    namespace HeatMapSample {
        public partial class Form1 : Form {
            public Form1() {
                InitializeComponent();
            }
            private void Form1_Load(object sender, EventArgs e) {
    
                ImageLayer bingLayer = new ImageLayer();
                bingLayer.DataProvider = new BingMapDataProvider { BingKey = "Your Bing Maps key here." };
                mapControl1.Layers.Add(bingLayer);
    
                ChoroplethColorizer colorizer = new ChoroplethColorizer();
                colorizer.RangeStops.AddRange(new double[] { 0.1, 0.2, 0.7, 1 });
                colorizer.ColorItems.Add(new ColorizerColorItem(Color.FromArgb(50, 128, 255, 0)));
                colorizer.ColorItems.Add(new ColorizerColorItem(Color.FromArgb(255, 255, 255, 0)));
                colorizer.ColorItems.Add(new ColorizerColorItem(Color.FromArgb(255, 234, 72, 58)));
                colorizer.ColorItems.Add(new ColorizerColorItem(Color.FromArgb(255, 162, 36, 25)));
                colorizer.ApproximateColors = true;
    
                HeatmapDataSourceAdapter adapter = new HeatmapDataSourceAdapter();
                adapter.Mappings.XCoordinate = "glon"; // The data source field name that provides x-coordinates.
                adapter.Mappings.YCoordinate = "glat"; // The data source field name that provides y-coordinates.
                adapter.DataSource = LoadData("../../Data/Earthquakes.xml", "Row");
    
                HeatmapProvider provider = new HeatmapProvider();
                provider.PointSource = adapter;
                provider.Algorithm = new HeatmapDensityBasedAlgorithm { PointRadius = 8 };
                provider.Colorizer = colorizer;
    
                ImageLayer heatmapLayer = new ImageLayer();
                heatmapLayer.DataProvider = provider;
                mapControl1.Layers.Add(heatmapLayer);
    
                ColorScaleLegend legend = new ColorScaleLegend();
                legend.Header = "Seismic Density";
                legend.EnableGradientScale = true;
                legend.Layer = heatmapLayer;
                legend.HeaderStyle.Font = new Font("Tahoma", 12F);
                mapControl1.Legends.Add(legend);
            }
            DataTable LoadData(string filePath, string tableName) {
                DataSet xmlDataSet = new DataSet("XML DataSet");
                xmlDataSet.ReadXml(filePath);
                return xmlDataSet.Tables[tableName];
            }
        }
    }
    

    #Inheritance

    Object
    HeatmapDataSourceAdapter
    See Also