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Disabling Controls in Node

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TreeView
This is a migrated thread and some comments may be shown as answers.
Brad
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Brad asked on 09 Mar 2011, 06:51 PM
I'm adding  nodes to the treeview at page load. Also at the same time I am adding a Label and a DropDown control to the node.

I want to disable the DropDowns for certain nodes  based on what node was checked. The Error I'm getting is :
"Object reference not set to an instance of an object."

This is because the the TreeView1.Nodes(0).Nodes(i).Count is 0. But it shouldn't be.

Does anyone know what I'm doing wrong here?


Heres how I am creating the nodes:
            For i As Integer = 0 To DsStateDistrictID.Tables(0).Rows.Count - 1
                Dim treeNode As New Telerik.Web.UI.RadTreeNode(DsStateDistrictID.Tables(0).Rows(i).Item("DistrictName").ToString)
                treeNode.Value = DsStateDistrictID.Tables(0).Rows(i).Item("StateDistrictID").ToString
                treeNode.Checkable = True

                'Add Label with StateDistrict Name to Node
                Dim lbl As Label = New Label
                lbl.Text = DsStateDistrictID.Tables(0).Rows(i).Item("DistrictName").ToString
                lbl.ID = "lbl" & DsStateDistrictID.Tables(0).Rows(i).Item("StateDistrictID").ToString.Trim
                treeNode.Controls.Add(lbl)

                'Add Color DropDown to Node
                Dim ddColor As DropDownList = New DropDownList
                ddColor.ID = "dd" '& DsStateDistrictID.Tables(0).Rows(i).Item("StateDistrictID").ToString.Trim
                ddColor = BuildColorDropDown(ddColor)
                treeNode.Controls.Add(ddColor)
                TreeView1.Nodes(0).Nodes.Add(treeNode)


            Next


        End If


Heres how I am trying to disable the drop down list:
For i As Integer = 0 To TreeView1.Nodes(0).Nodes.Count - 1
                    Dim StateDistrictID As String = TreeView1.Nodes(0).Nodes(i).Value.ToString.Trim
                    Dim ddColor As New DropDownList
                    ddColor = CType(TreeView1.Nodes(0).Nodes(i).FindControl("dd" & StateDistrictID), DropDownList)
                    ddColor.Enabled = False
Next

No answers yet. Maybe you can help?

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