TreemapDashboardItem Class

using DevExpress.DashboardCommon;
using DevExpress.XtraEditors;

namespace DashboardViewer_Treemap {
    public partial class Form1 : XtraForm {
        public Form1() {
            InitializeComponent();

            Dashboard dashboard = new Dashboard();

            DashboardExtractDataSource dataSource = new DashboardExtractDataSource();
            dataSource.FileName = @"..\..\Data\SalesDataExtract.dat";
            dashboard.DataSources.Add(dataSource);

            TreemapDashboardItem treeMap = new TreemapDashboardItem();
            treeMap.DataSource = dataSource;
            treeMap.Values.Add(new Measure("Sales"));            
            treeMap.Arguments.Add(new Dimension { DataMember = "Product Category", GroupChildValues = true });
            treeMap.Arguments.Add(new Dimension("Product Sub-Category"));
            treeMap.LayoutAlgorithm = DashboardTreemapLayoutAlgorithm.Striped;

            dashboard.Items.Add(treeMap);
            dashboardViewer1.Dashboard = dashboard;
        }
    }
}

Imports DevExpress.DashboardCommon
Imports DevExpress.XtraEditors

Namespace DashboardViewer_Treemap
    Partial Public Class Form1
        Inherits XtraForm

        Public Sub New()
            InitializeComponent()

            Dim dashboard As New Dashboard()

            Dim dataSource As New DashboardExtractDataSource()
            dataSource.FileName = "..\..\Data\SalesDataExtract.dat"
            dashboard.DataSources.Add(dataSource)

            Dim treeMap As New TreemapDashboardItem()
            treeMap.DataSource = dataSource
            treeMap.Values.Add(New Measure("Sales"))
            treeMap.Arguments.Add(New Dimension With {.DataMember = "Product Category", .GroupChildValues = True})
            treeMap.Arguments.Add(New Dimension("Product Sub-Category"))
            treeMap.LayoutAlgorithm = DashboardTreemapLayoutAlgorithm.Striped

            dashboard.Items.Add(treeMap)
            dashboardViewer1.Dashboard = dashboard
        End Sub
    End Class
End Namespace