Binding to Self Referencing Data
Binding RadTreeView to self referencing data differs from binding to related data in that RadTreeView is bound to a single list instead of multiple related lists.
In order to set the parent-child relation between the records of the data source, we should set the ParentMember and ChildMember properties to the respective fields in the data source. If the parent ID for a record does not have a respective value in the child ID field of the records, then that record is considered to have no parents.
All parent identifiers must be positive numbers.
Minimal example
The following example demonstrates how to bind RadTreeView to a self referencing DataTable.
public BindingToSelfRefData()
{
InitializeComponent();
this.radTreeView1.DisplayMember = "name";
this.radTreeView1.ParentMember = "pid";
this.radTreeView1.ChildMember = "id";
this.radTreeView1.DataSource = this.GetSampleData();
}
private DataTable GetSampleData()
{
DataTable dt = new DataTable();
DataColumn dc = new DataColumn();
dc.ColumnName = "id";
dc.DataType = typeof(int);
dt.Columns.Add(dc);
DataColumn dc1 = new DataColumn();
dc1.ColumnName = "name";
dc1.DataType = typeof(string);
dt.Columns.Add(dc1);
DataColumn dc2 = new DataColumn();
dc2.ColumnName = "pid";
dc2.DataType = typeof(int);
dt.Columns.Add(dc2);
DataRow dr = dt.NewRow();
dr[0] = 0;
dr[1] = "My Computer";
dr[2] = DBNull.Value;
dt.Rows.Add(dr);
dr = dt.NewRow();
dr[0] = 1;
dr[1] = @"C:\";
dr[2] = 0;
dt.Rows.Add(dr);
dr = dt.NewRow();
dr[0] = 2;
dr[1] = @"D:\";
dr[2] = 0;
dt.Rows.Add(dr);
dr = dt.NewRow();
dr[0] = 3;
dr[1] = "Program Files";
dr[2] = 1;
dt.Rows.Add(dr);
dr = dt.NewRow();
dr[0] = 4;
dr[1] = "Microsoft";
dr[2] = 3;
dt.Rows.Add(dr);
dr = dt.NewRow();
dr[0] = 5;
dr[1] = "Telerik";
dr[2] = 3;
dt.Rows.Add(dr);
dr = dt.NewRow();
dr[0] = 6;
dr[1] = "WINDOWS";
dr[2] = 1;
dt.Rows.Add(dr);
return dt;
}
Public Sub New()
InitializeComponent()
Me.RadTreeView1.DisplayMember = "name"
Me.RadTreeView1.ParentMember = "pid"
Me.RadTreeView1.ChildMember = "id"
Me.RadTreeView1.DataSource = Me.GetSampleData()
End Sub
Private Function GetSampleData() As DataTable
Dim dt As New DataTable()
Dim dc As New DataColumn()
dc.ColumnName = "id"
dc.DataType = GetType(Integer)
dt.Columns.Add(dc)
Dim dc1 As New DataColumn()
dc1.ColumnName = "name"
dc1.DataType = GetType(String)
dt.Columns.Add(dc1)
Dim dc2 As New DataColumn()
dc2.ColumnName = "pid"
dc2.DataType = GetType(Integer)
dt.Columns.Add(dc2)
Dim dr As DataRow = dt.NewRow()
dr(0) = 0
dr(1) = "My Computer"
dr(2) = DBNull.Value
dt.Rows.Add(dr)
dr = dt.NewRow()
dr(0) = 1
dr(1) = "C:\"
dr(2) = 0
dt.Rows.Add(dr)
dr = dt.NewRow()
dr(0) = 2
dr(1) = "D:\"
dr(2) = 0
dt.Rows.Add(dr)
dr = dt.NewRow()
dr(0) = 3
dr(1) = "Program Files"
dr(2) = 1
dt.Rows.Add(dr)
dr = dt.NewRow()
dr(0) = 4
dr(1) = "Microsoft"
dr(2) = 3
dt.Rows.Add(dr)
dr = dt.NewRow()
dr(0) = 5
dr(1) = "Telerik"
dr(2) = 3
dt.Rows.Add(dr)
dr = dt.NewRow()
dr(0) = 6
dr(1) = "WINDOWS"
dr(2) = 1
dt.Rows.Add(dr)
Return dt
End Function
As a result we get the hierarchy of nodes shown below:
