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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.Xpf.Map

    Assembly: DevExpress.Xpf.Map.v25.1.dll

    NuGet Package: DevExpress.Wpf.Map

    #Declaration

    public class HeatmapDataSourceAdapter :
        HeatmapPointSourceBase,
        IWeakEventListener,
        IMapDataSourceAdapter

    #Example

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

    Markup

    <Window
            xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
            xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
            xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
            xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
            xmlns:local="clr-namespace:Heatmap"
            xmlns:dxm="http://schemas.devexpress.com/winfx/2008/xaml/map" 
            x:Class="Heatmap.MainWindow"
            mc:Ignorable="d"
            Title="MainWindow" Height="450" Width="800">
        <Window.DataContext>
            <local:EarthquakesData/>
        </Window.DataContext>
        <Grid>
            <dxm:MapControl ZoomLevel="2">
                <dxm:ImageLayer>
                    <dxm:BingMapDataProvider BingKey="Your Bing Maps key here."/>
                </dxm:ImageLayer>
                <!-- The heatmap layer configuration -->
                <dxm:ImageLayer Name="heatmapLayer" Opacity="0.75">
                    <dxm:HeatmapProvider>
                        <dxm:HeatmapProvider.Colorizer>
                            <dxm:ChoroplethColorizer RangeStops="0.1, 0.2, 0.7, 1.0" 
                                                     ApproximateColors="True">
                                <dxm:ChoroplethColorizer.Colors>
                                    <Color A="50"  R="128"  G="255"  B="0"/>
                                    <Color A="255" R="255"  G="255"  B="0"/>
                                    <Color A="255" R="234"  G="72"   B="58"/>
                                    <Color A="255" R="162"  G="36"   B="25"/>
                                </dxm:ChoroplethColorizer.Colors>
                            </dxm:ChoroplethColorizer>
                        </dxm:HeatmapProvider.Colorizer>
                        <dxm:HeatmapProvider.PointSource>
                            <dxm:HeatmapDataSourceAdapter DataSource="{Binding Path=DataItems}">
                                <dxm:HeatmapDataSourceAdapter.Mappings>
                                    <dxm:HeatmapPointMappingInfo XCoordinate="Longitude" 
                                                                 YCoordinate="Latitude"/>
                                </dxm:HeatmapDataSourceAdapter.Mappings>
                            </dxm:HeatmapDataSourceAdapter>
                        </dxm:HeatmapProvider.PointSource>
                        <dxm:HeatmapProvider.Algorithm>
                            <dxm:HeatmapDensityBasedAlgorithm PointRadius="10"/>
                        </dxm:HeatmapProvider.Algorithm>
                    </dxm:HeatmapProvider>
                </dxm:ImageLayer>
                <!--...-->
            </dxm:MapControl>
        </Grid>
    </Window>
    

    Code-Behind

    using System;
    using System.Collections.Generic;
    using System.IO;
    using System.Windows;
    using System.Xml.Serialization;
    namespace Heatmap {
        public partial class MainWindow : Window {
            public MainWindow() {
                InitializeComponent();
            }
        }
        public class EarthquakeViewModel {
            [XmlElement("glat")]
            public double Latitude { get; set; }
            [XmlElement("glon")]
            public double Longitude { get; set; }
        }
        [XmlRoot("Data")]
        public class EarthquakesData {
            static EarthquakesData instance;
            public static List<EarthquakeViewModel> DataItems {
                get { return Instance.Items; }
            }
            public static EarthquakesData Instance {
                get { return instance ?? (instance = CreateInstance()); }
            }
            static EarthquakesData CreateInstance() {
                XmlSerializer serializer = new XmlSerializer(typeof(EarthquakesData));
                Stream documentStream = LoadStreamFromResources("/Data/Earthquakes.xml");
                return (EarthquakesData)serializer.Deserialize(documentStream);
            }
            [XmlElement("Row")]
            public List<EarthquakeViewModel> Items { get; set; }
            public static Stream LoadStreamFromResources(string fileName) {
                try {
                    Uri uri = new Uri(fileName, UriKind.RelativeOrAbsolute);
                    return Application.GetResourceStream(uri).Stream;
                }
                catch {
                    return null;
                }
            }
        }
    }
    
    See Also