树控件的VBA问题

有个下面表格 テーブル1

窗体中有树treeview1

代码

Private Sub Form_Load()
Dim i As Integer
Dim j As Integer
Dim str As String
Dim strkey As String
Dim nodx As Node
Dim cn As ADODB.Connection
Dim Rs As ADODB.Recordset
Dim cunzai As Boolean
Dim ilevel As Integer
Dim strparent As String
Dim var As Variant
Dim k As Integer
Dim itemp As Integer

Me.treeview1.LineStyle = tvwTreeLines
itemp = 0
For i = 1 To i
str = "select * from テーブル1 where 級別=' & i & '"
Rs.Open str, CurrentProject.Connection, adOpenKeyset, adLockOptimistic
  If Rs.RecordCount = 0 Then
    Rs.Close
    Exit Sub
  End If
    Rs.MoveFirst
  If i = 1 Then
    Do While Not (Rs.EOF)
      itemp = itemp + 1
 
  Set nodx = Me.treeview1.Nodes.Add(, , Rs("単位名称"), Rs("単位名称"))
  treeview1.Nodes(itemp).Expanded = True
  Rs.MoveNext
  Loop
  Else
  Do While Not (Rs.EOF)
  itemp = itemp + 1
  str = Rs("父節点")
  Set nodx = Me.treeview1.Nodes.Add(str, tvwChild, Rs("単位名称"), Rs("単位名称"))
  treeview1.Nodes(itemp).Expanded = True
  Rs.MoveNext
  Loop
  End If
  Rs.Close
  Next i
  Me.treeview1.Refresh
   Set Rs = Nothing
End Sub

请问高手，为什么运行窗口的时候树显示不出来呢？

哪里有错误？该怎么修改呢？

谢谢