Leaf Nodes Customization in WPF TreeMap

You can customize the leaf nodes by assigning a data template to the LeafTemplate of WPF TreeMap.

<Grid Background="Black">
    <Grid.DataContext>
        <local:OlymicMedalsViewModel />
    </Grid.DataContext>

    <syncfusion:SfTreeMap ItemsSource="{Binding OlympicMedalsDetails}"
                          Margin="50"
                          WeightValuePath="TotalMedals"
                          ColorValuePath="GoldMedals">
        <syncfusion:SfTreeMap.LeafTemplate>
            <DataTemplate>
                <Border Background="#D73028"
                        BorderBrush="Transparent"
                        BorderThickness="3">
                    <Image Source="{Binding Data.GameImgSource}"
                           Margin="0,25,0,0"
                           HorizontalAlignment="Center"
                           VerticalAlignment="Center"
                           Stretch="None" />
                </Border>
            </DataTemplate>
        </syncfusion:SfTreeMap.LeafTemplate>

        <syncfusion:SfTreeMap.Levels>
            <syncfusion:TreeMapFlatLevel GroupPath="GameName"
                                         ShowLabels="True">
                <syncfusion:TreeMapFlatLevel.LabelTemplate>
                    <DataTemplate>
                        <TextBlock Text="{Binding Label}"
                                   Padding="10,5,0,0"
                                   FontSize="20"
                                   HorizontalAlignment="Left"
                                   VerticalAlignment="Top" />
                    </DataTemplate>
                </syncfusion:TreeMapFlatLevel.LabelTemplate>
            </syncfusion:TreeMapFlatLevel>
        </syncfusion:SfTreeMap.Levels>
    </syncfusion:SfTreeMap>
</Grid>
public class OlymicMedalsViewModel
{
    public ObservableCollection<OlympicMedals> OlympicMedalsDetails { get; set; }

    public OlymicMedalsViewModel()
    {
        this.OlympicMedalsDetails = new ObservableCollection<OlympicMedals>();

        this.OlympicMedalsDetails.Add(
            new OlympicMedals
            {
                Country = "US",
                GameName = "Swimming",
                GoldMedals = 16,
                SilverMedals = 9,
                BronzeMedals = 6,
                TotalMedals = 31,
                GameImgSource = new BitmapImage(
                    new Uri("ms-appx:/Assets/Swimming.png"))
            });

        this.OlympicMedalsDetails.Add(
            new OlympicMedals
            {
                Country = "US",
                GameName = "Track and Field",
                GoldMedals = 9,
                SilverMedals = 13,
                BronzeMedals = 7,
                TotalMedals = 29,
                GameImgSource = new BitmapImage(
                    new Uri("ms-appx:/Assets/TrackAndField.png"))
            });

        this.OlympicMedalsDetails.Add(
            new OlympicMedals
            {
                Country = "US",
                GameName = "Gymnastics",
                GoldMedals = 3,
                SilverMedals = 1,
                BronzeMedals = 2,
                TotalMedals = 6,
                GameImgSource = new BitmapImage(
                    new Uri("ms-appx:/Assets/Gymnastics.png"))
            });

        this.OlympicMedalsDetails.Add(
            new OlympicMedals
            {
                Country = "US",
                GameName = "Cycling",
                GoldMedals = 1,
                SilverMedals = 2,
                BronzeMedals = 1,
                TotalMedals = 4,
                GameImgSource = new BitmapImage(
                    new Uri("ms-appx:/Assets/Cycling.png"))
            });

        this.OlympicMedalsDetails.Add(
            new OlympicMedals
            {
                Country = "US",
                GameName = "Shooting",
                GoldMedals = 3,
                SilverMedals = 0,
                BronzeMedals = 1,
                TotalMedals = 4,
                GameImgSource = new BitmapImage(
                    new Uri("ms-appx:/Assets/Shooting.png"))
            });

        this.OlympicMedalsDetails.Add(
            new OlympicMedals
            {
                Country = "US",
                GameName = "Wrestling",
                GoldMedals = 2,
                SilverMedals = 0,
                BronzeMedals = 2,
                TotalMedals = 4,
                GameImgSource = new BitmapImage(
                    new Uri("ms-appx:/Assets/Wrestling.png"))
            });

        this.OlympicMedalsDetails.Add(
            new OlympicMedals
            {
                Country = "US",
                GameName = "Diving",
                GoldMedals = 1,
                SilverMedals = 1,
                BronzeMedals = 2,
                TotalMedals = 4,
                GameImgSource = new BitmapImage(
                    new Uri("ms-appx:/Assets/Diving.png"))
            });
    }
}

public class OlympicMedals
{
    public string Country { get; set; }

    public string GameName { get; set; }

    public double GoldMedals { get; set; }

    public double SilverMedals { get; set; }

    public double BronzeMedals { get; set; }

    public double TotalMedals { get; set; }

    public ImageSource GameImgSource { get; set; }
}

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