need help with treeview PLEASE!!

[spdracr]

ok, i have a collection that i need to populate a treeview with. i can get the root nodes in and child nodes under that, but i also need to get some child nodes under the already child nodes.

how can i do this...

also, does anybody have a good way of sending a collection to a treeview. all examples i have seen use an array. using an array seems to work a bit easier seeing how you have indexes to work with and you don't with a collection.

but hey, maybe i'm just screwed in the head and don't know what i'm talking about... i've only been using vb.net for 2 days now.

thanks

[RichardAtherton]

Yes had the same problem intially, then found somegeneric code which showed how to polate a treeview and indent as much as you like.

I'm going to ppost my own code here. For our appplication, which inhererit the treeview control to add additonal properties, so I've included that class as well:

I did post this previously using another exampple, hopefully between the two examples you will work it out.

Fist the inherited node class:

Public Class TfrNode
Inherits TreeNode

Public Name As String
Public Landlord As Integer
Public Proprty As Integer
Public Unit As Integer
Public Tenancy As Integer


Sub New(ByVal Desc As String, ByVal Landlord1 As Integer, ByVal Proprty1 As Integer, ByVal Unit1 As Integer, ByVal Tenancy1 As Integer)
MyBase.New()
Name = Desc
Landlord = Landlord1
Proprty = Proprty1
Unit = Unit1
Tenancy = Tenancy1
Me.Text = Name
End Sub

End Class

Now the code which reads from the datasets and popluates three tree view, this indent to a level of 3,but as you can see the code is structured toallow more indentation if required.

Private Sub Populatetree()
Dim OledbStr As String = "Select Landlord,Name,Adr1,Adr2 from Landlords where (DateRemoved Is Null)"

Dim Cmd1 As OledbCommand = New OledbCommand(OledbStr, Cn1)
Cn1.Open()
Cn2.Open()
Cn3.Open()
Cn4.Open()
Dim dt1 As OledbDataReader = Cmd1.ExecuteReader()
TreeView1.BeginUpdate()
TreeView1.Nodes.Clear()
Dim AllNode As New TfrNode("Landlords", 0, 0, 0, 0)
TreeView1.Nodes.Add(AllNode)
' Build Landlords list
Dim BalTfr As Boolean
While dt1.Read
BalTfr = LandlordBal(dt1("Landlord"))

If BalTfr Then
Dim LanNode As New TfrNode(Trim(dt1("Name")) & " " & Trim(dt1("Adr1")) & "," & Trim(dt1("Adr2")), dt1("Landlord"), 0, 0, 0)
AllNode.Nodes.Add(LanNode)
' buid landlord properties list
OledbStr = "Select Proprty,Adr1,Adr2,Locality from Properties where (DateRemoved Is Null)and Landlord = " & CStr(dt1("Landlord"))
Dim Cmd2 As OledbCommand = New OledbCommand(OledbStr, Cn2)
Dim dt2 As OledbDataReader = Cmd2.ExecuteReader()
While dt2.Read
BalTfr = PropBal(dt2("Proprty"))


If BalTfr Then
Dim PropNode As New TfrNode((Trim(dt2("Adr1")) & "," & Trim(dt2("Adr2")) & "," & Trim(dt2("Locality"))), dt1("Landlord"), dt2("Proprty"), 0, 0)
LanNode.Nodes.Add(PropNode)
' build units list for this Proprty
OledbStr = "Select Proprty,Unit,PropertyAdr from PropertyUnits where (DateRemoved Is Null) and Proprty = " & CStr(dt2("Proprty"))
Dim Cmd3 As OledbCommand = New OledbCommand(OledbStr, Cn3)
Dim dt3 As OledbDataReader = Cmd3.ExecuteReader()

While dt3.Read
BalTfr = UnitBal(dt2("Proprty"), dt3("Unit"))

If BalTfr Then
OledbStr = "Select Tenancy,Proprty,Unit,LeadTenant from Tenancies where (DateRemoved Is Null) and Proprty = " & CStr(dt2("Proprty")) & " and Unit = " & CStr(dt3("Unit"))
Dim Cmd4 As OledbCommand = New OledbCommand(OledbStr, Cn4)
da4.SelectCommand = Cmd4
ds4.Clear()
Dim found As Integer = da4.Fill(ds4, "Tenancies")
Dim Details As String
Dim tenancy As Integer
If found > 0 Then
Dr4 = ds4.Tables.Item("Tenancies").Rows(0)
tenancy = Dr4("Tenancy")
Details = Trim(dt3("PropertyAdr")) & "," & Trim(Dr4("LeadTenant"))
Else
tenancy = 0
Details = dt3("PropertyAdr")
End If

Dim UnitNode As New TfrNode(Details, dt1("Landlord"), dt2("Proprty"), dt3("Unit"), tenancy)
PropNode.Nodes.Add(UnitNode)

Cmd4 = Nothing
End If

End While
dt3.Close()
Cmd3 = Nothing

End If
End While
dt2.Close()
Cmd2 = Nothing
End If
End While
TreeView1.EndUpdate()
Cmd1 = Nothing
Cn1.Close()
Cn2.Close()
Cn3.Close()
Cn4.Close()
End Sub

Don't worry about the specifics, it is simply a question of starting at the root node, then adding all levels between the next branch in the tree before moving onto the next branch at the same level.