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TreeList Class

Displays data as a multi-column tree view. Can be used in either bound or unbound mode. See Tree List for more information.

Namespace: DevExpress.XtraTreeList

Assembly: DevExpress.XtraTreeList.v23.2.dll

NuGet Packages: DevExpress.Win.Navigation, DevExpress.Win.TreeList

Declaration

[TreeList.TreeListCustomBindingProperties]
public class TreeList :
    EditorContainer,
    ISupportAsyncScrollAnimation,
    IFilterPanelOwner,
    ISupportFilterCriteriaDisplayStyle,
    IDxHtmlDesignerDataProvider,
    IDxHtmlRepositoryOwner,
    ISupportCommandBindingForElements<string>,
    IHyperLinkOwner<TreeListHyperlinkClickEventArgs>,
    ISupportExpandAnimation,
    ISupportXtraAnimation,
    IControlRowSource,
    IFilteringUIClient,
    IFilterCriteriaBindingAware,
    IScrollBarAnnotationsOwner<ScrollAnnotationKind>,
    IScrollBarOwner,
    IPrintableEx,
    IPrintable,
    IBasePrintable,
    IXtraSerializable,
    INavigatableControl,
    IToolTipControlClient,
    IAppearanceOwner,
    IDXManagerPopupMenu,
    IAccessibleGrid,
    IXtraSerializableLayout,
    IEvaluatorDataAccess,
    IXtraSerializableLayoutEx,
    ISupportXtraSerializer,
    IGestureClient,
    IServiceProvider,
    IStringSvgImageProvider,
    IStringImageProvider,
    IFilteredComponent,
    IFilteredComponentBase,
    ISearchControlColumnsClient,
    ISearchControlClient,
    IOptionsLayoutProvider,
    IXtraSerializableLayout2,
    IXtraSupportAllowProperty,
    ISupportDesignMode

Remarks

The Tree List displays data with parent-child relations as nodes organized into a hierarchy.

Tree List - Simple

The control supports bound and unbound modes. In bound mode, data is loaded from an external data source specified by the TreeList.DataSource and TreeList.DataMember properties. A data source must contain two fields that supply information on parent-child relationships between records: a unique record ID (key) and a parent record ID. These fields must be assigned to the TreeList.KeyFieldName and TreeList.ParentFieldName properties.

In unbound mode, you need to populate the TreeList with nodes manually. You can either create all nodes at once, or start with root nodes only and generate child nodes on demand. See Unbound Mode for more information.

The main TreeList features are:

Use the TreeList.Columns property to access the column collection. At design time, you can create columns in the Tree List Designer. See Columns for more information.

The collection of root level nodes is stored in the TreeList.Nodes property. Child nodes of each node are stored in the node’s TreeListNode.Nodes collection. See Nodes for information on node objects, node structure, and how to iterate through nodes.

Note

If the TreeList control is created at design time, you cannot change the visual settings or size of the control and its elements (for example, by invoking the best fit functionality) until the Tree List has completed its initialization. To customize these settings in the form’s System.Windows.Forms.Form.Load event handler, call the TreeList.ForceInitialize method prior to performing additional customization.

Example

The following example creates a TreeList at runtime and shows how to perform basic customization tasks:

  • Bind the treelist to a data source
  • Specify the key fields that form a hierarchy
  • Access automatically created columns
  • Set a custom row height
  • Customize column captions (using HTML tags) and cell appearance settings
  • Create unbound columns and create Excel-style format conditions based on these column values
  • Assign an in-place editor (a spin editor) to columns
  • Sort data
  • Calculate total summaries
  • Filter nodes
  • Hide columns and calculate column “best” widths
  • Locate and expand nodes
  • Focus a specific cell
  • Specify DataAnnotation attributes at the data source level (the “p0” display format for the MarketShare field)

Treelist-create-at-runtime

using DevExpress.XtraEditors;
using DevExpress.XtraEditors.Repository;
using DevExpress.XtraTreeList;
using DevExpress.XtraTreeList.Columns;
using DevExpress.XtraTreeList.Nodes;
using DevExpress.XtraTreeList.StyleFormatConditions;
using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Windows.Forms;

namespace TreeList_example {
    public partial class Form1 : Form {
        public Form1() {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e) {
            TreeList treeList1 = new TreeList();
            treeList1.Parent = this;
            treeList1.Dock = DockStyle.Fill; 
            //Specify the fields that arrange underlying data as a hierarchy.
            treeList1.KeyFieldName = "ID";
            treeList1.ParentFieldName = "RegionID";
            //Allow the treelist to create columns bound to the fields the KeyFieldName and ParentFieldName properties specify.
            treeList1.OptionsBehavior.PopulateServiceColumns = true;
            //Specify the data source.
            treeList1.DataSource = SalesDataGenerator.CreateData();
            //The treelist automatically creates columns for the public fields found in the data source. 
            //You do not need to call the TreeList.PopulateColumns method unless the treeList1.OptionsBehavior.AutoPopulateColumns option is disabled.

            //Change the row height.
            treeList1.RowHeight = 23;

            //Access the automatically created columns.
            TreeListColumn colRegion = treeList1.Columns["Region"];
            TreeListColumn colMarchSales = treeList1.Columns["MarchSales"];
            TreeListColumn colSeptemberSales = treeList1.Columns["SeptemberSales"];
            TreeListColumn colMarchSalesPrev = treeList1.Columns["MarchSalesPrev"];
            TreeListColumn colSeptemberSalesPrev = treeList1.Columns["SeptemberSalesPrev"];
            TreeListColumn colMarketShare = treeList1.Columns["MarketShare"];

            //Hide the key columns. An end user can access them from the Customization Form.
            treeList1.Columns[treeList1.KeyFieldName].Visible = false;
            treeList1.Columns[treeList1.ParentFieldName].Visible = false;

            //Format column headers and cell values.
            colMarchSalesPrev.Caption = "<i>Previous <b>March</b> Sales</i>";
            colSeptemberSalesPrev.Caption = "<i>Previous <b>September</b> Sales</i>";
            treeList1.OptionsView.AllowHtmlDrawHeaders = true;
            colMarchSalesPrev.AppearanceCell.Font = new System.Drawing.Font(colMarchSalesPrev.AppearanceCell.Font, System.Drawing.FontStyle.Italic);
            colSeptemberSalesPrev.AppearanceCell.Font = new System.Drawing.Font(colSeptemberSalesPrev.AppearanceCell.Font, System.Drawing.FontStyle.Italic);

            //Create two hidden unbound columns that calculate their values from expressions.
            TreeListColumn colUnboundMarchChange = treeList1.Columns.AddField("FromPrevMarchChange");
            colUnboundMarchChange.Caption = "Change from prev March";
            colUnboundMarchChange.UnboundDataType = typeof(decimal);
            colUnboundMarchChange.UnboundExpression = "[MarchSales]-[MarchSalesPrev]";
            TreeListColumn colUnboundSeptemberChange = treeList1.Columns.AddField("FromPrevSepChange");
            colUnboundSeptemberChange.Caption = "Change from prev September";
            colUnboundSeptemberChange.UnboundDataType = typeof(decimal);
            colUnboundSeptemberChange.UnboundExpression = "[SeptemberSales]-[SeptemberSalesPrev]";
            colUnboundMarchChange.OptionsColumn.ShowInCustomizationForm = false;
            colUnboundSeptemberChange.OptionsColumn.ShowInCustomizationForm = false;

            //Make the Region column read-only.
            colRegion.OptionsColumn.ReadOnly = true;

            //Sort data against the Region column.
            colRegion.SortIndex = 0;

            //Apply a filter.
            treeList1.ActiveFilterString = "[MarchSales] > 10000";

            //Calculate two total summaries against root nodes.
            colMarchSales.SummaryFooter = DevExpress.XtraTreeList.SummaryItemType.Sum;
            colMarchSales.SummaryFooterStrFormat = "Total={0:c0}";
            colMarchSales.AllNodesSummary = false;
            colSeptemberSales.SummaryFooter = DevExpress.XtraTreeList.SummaryItemType.Sum;
            colSeptemberSales.SummaryFooterStrFormat = "Total={0:c0}";
            colSeptemberSales.AllNodesSummary = false;
            treeList1.OptionsView.ShowSummaryFooter = true;

            //Use a 'SpinEdit' in-place editor for the 'sales' columns.
            RepositoryItemSpinEdit riSpinEdit = new RepositoryItemSpinEdit();
            riSpinEdit.DisplayFormat.FormatType = DevExpress.Utils.FormatType.Numeric;
            riSpinEdit.DisplayFormat.FormatString = "c0";
            treeList1.RepositoryItems.Add(riSpinEdit);
            colMarchSales.ColumnEdit = riSpinEdit;
            colMarchSalesPrev.ColumnEdit = riSpinEdit;
            colSeptemberSales.ColumnEdit = riSpinEdit;
            colSeptemberSalesPrev.ColumnEdit = riSpinEdit;

            //Apply Excel-style formatting: display predefined 'Up Arrow' and 'Down Arrow' icons based on the unbound column values.
            TreeListFormatRule rule1 = new TreeListFormatRule();
            rule1.Rule = createThreeTrianglesIconSetRule();
            rule1.Column = colUnboundMarchChange;
            rule1.ColumnApplyTo = colMarchSales;
            TreeListFormatRule rule2 = new TreeListFormatRule();
            rule2.Rule = createThreeTrianglesIconSetRule();
            rule2.Column = colUnboundSeptemberChange;
            rule2.ColumnApplyTo = colSeptemberSales;
            treeList1.FormatRules.Add(rule1);
            treeList1.FormatRules.Add(rule2);

            //Do not stretch columns to the treelist width.
            treeList1.OptionsView.AutoWidth = false;

            //Locate a node by a value it contains.
            TreeListNode node1 = treeList1.FindNodeByFieldValue("Region", "North America");
            //Focus and expand this node.
            treeList1.FocusedNode = node1;
            node1.Expanded = true;

            //Locate a node by its key field value and expand it.
            TreeListNode node2 = treeList1.FindNodeByKeyID(32);//Node 'Asia'
            node2.Expand();

            //Calculate the optimal column widths after the treelist is shown.
            this.BeginInvoke(new MethodInvoker(delegate {
                treeList1.BestFitColumns();
            }));
        }

        FormatConditionRuleIconSet createThreeTrianglesIconSetRule() {
            FormatConditionRuleIconSet ruleIconSet = new FormatConditionRuleIconSet();
            FormatConditionIconSet iconSet = ruleIconSet.IconSet = new FormatConditionIconSet();
            FormatConditionIconSetIcon icon1 = new FormatConditionIconSetIcon();
            FormatConditionIconSetIcon icon2 = new FormatConditionIconSetIcon();
            FormatConditionIconSetIcon icon3 = new FormatConditionIconSetIcon();
            //Choose predefined icons. 
            icon1.PredefinedName = "Triangles3_3.png";
            icon2.PredefinedName = "Triangles3_2.png";
            icon3.PredefinedName = "Triangles3_1.png";
            //Specify the type of threshold values. 
            iconSet.ValueType = FormatConditionValueType.Number;
            //Define ranges to which icons are applied by setting threshold values. 
            icon1.Value = Decimal.MinValue;
            icon1.ValueComparison = FormatConditionComparisonType.GreaterOrEqual;
            icon2.Value = 0;
            icon2.ValueComparison = FormatConditionComparisonType.GreaterOrEqual;
            icon3.Value = 0;
            icon3.ValueComparison = FormatConditionComparisonType.Greater;
            //Add icons to the icon set. 
            iconSet.Icons.Add(icon1);
            iconSet.Icons.Add(icon2);
            iconSet.Icons.Add(icon3);
            return ruleIconSet;
        }
    }

    public class SalesData {
        static int UniqueID = 37;
        public SalesData() {
            ID = UniqueID++;
        }
        public SalesData(int id, int regionId, string region, decimal marchSales, decimal septemberSales, decimal marchSalesPrev, decimal septermberSalesPrev, double marketShare) {
            ID = id;
            RegionID = regionId;
            Region = region;
            MarchSales = marchSales;
            SeptemberSales = septemberSales;
            MarchSalesPrev = marchSalesPrev;
            SeptemberSalesPrev = septermberSalesPrev;
            MarketShare = marketShare;
        }
        public int ID { get; set; }
        public int RegionID { get; set; }
        public string Region { get; set; }
        public decimal MarchSales { get; set; }
        public decimal SeptemberSales { get; set; }
        public decimal MarchSalesPrev { get; set; }
        public decimal SeptemberSalesPrev { get; set; }

        [DisplayFormat(DataFormatString = "p0")]
        public double MarketShare { get; set; }
    }

    public class SalesDataGenerator {
        public static List<SalesData> CreateData() {
            List<SalesData> sales = new List<SalesData>();
            sales.Add(new SalesData(0, -1, "Western Europe", 30540, 33000, 32220, 35500, .70));
            sales.Add(new SalesData(1, 0, "Austria", 22000, 28000, 26120, 28500, .92));
            sales.Add(new SalesData(2, 0, "France", 23020, 27000, 20120, 29200, .51));
            sales.Add(new SalesData(3, 0, "Germany", 30540, 33000, 32220, 35500, .93));
            sales.Add(new SalesData(4, 0, "Spain", 12900, 10300, 14300, 9900, .82));
            sales.Add(new SalesData(5, 0, "Switzerland", 9323, 10730, 7244, 9400, .14));
            sales.Add(new SalesData(6, 0, "United Kingdom", 14580, 13967, 15200, 16900, .91));

            sales.Add(new SalesData(17, -1, "Eastern Europe", 22500, 24580, 21225, 22698, .62));
            sales.Add(new SalesData(18, 17, "Belarus", 7315, 18800, 8240, 17480, .34));
            sales.Add(new SalesData(19, 17, "Bulgaria", 6300, 2821, 5200, 10880, .8));
            sales.Add(new SalesData(20, 17, "Croatia", 4200, 3890, 3880, 4430, .29));
            sales.Add(new SalesData(21, 17, "Russia", 22500, 24580, 21225, 22698, .85));

            sales.Add(new SalesData(26, -1, "North America", 31400, 32800, 30300, 31940, .84));
            sales.Add(new SalesData(27, 26, "USA", 31400, 32800, 30300, 31940, .87));
            sales.Add(new SalesData(28, 26, "Canada", 25390, 27000, 5200, 29880, .64));

            sales.Add(new SalesData(29, -1, "South America", 16380, 17590, 15400, 16680, .32));
            sales.Add(new SalesData(30, 29, "Argentina", 16380, 17590, 15400, 16680, .88));
            sales.Add(new SalesData(31, 29, "Brazil", 4560, 9480, 3900, 6100, .10));

            sales.Add(new SalesData(32, -1, "Asia", 20388, 22547, 22500, 25756, .52));
            sales.Add(new SalesData(34, 32, "India", 4642, 5320, 4200, 6470, .44));
            sales.Add(new SalesData(35, 32, "Japan", 9457, 12859, 8300, 8733, .70));
            sales.Add(new SalesData(36, 32, "China", 20388, 22547, 22500, 25756, .82));
            return sales;
        }
    }

}

Implements

See Also