BUG: Treeview Root Property Returns Reference to First Node

ID: Q149323

The information in this article applies to:

Microsoft Visual Basic Control Creation, Learning, Professional, and Enterprise Editions for Windows, version 5.0
Microsoft Visual Basic Standard, Professional, and Enterprise Editions, 32-bit only, for Windows, version 4.0

SYMPTOMS

The Node property of the TreeView custom control has a property named Root. The Help states that Root "returns a reference to the root Node object of a selected Node." Due to the way the Root property was designed, this statement isn't always true. The Root property of a Node always returns a reference to the first root level node; that is, it returns a reference to the first node that was added with this syntax:


   TreeView1.Nodes.Add , , , "MyText"

If the Root property is used with any descendant nodes of this first node, it will work correctly. However, if another root level node is added with the above line of code, then the Root property of all descendant nodes will still return a reference to the first node added.

RESOLUTION

To work around this problem, use the following small function to determine the Root node of a given node instead of the inherent Root property. FindRoot returns a reference to the correct root node for the specified Node object passed as a parameter.


   Function FindRoot(ByVal nodX As Node) As Node
       Dim n As Integer

       On Error GoTo ErrHandler

       n = nodX.Index
       While n <> nodX.Root.Index
           n = TreeView1.Nodes(n).Parent.Index
       Wend

   ErrHandler:
       Set FindRoot = TreeView1.Nodes(n)
   End Function

STATUS

Microsoft has confirmed this to be an issue in the Microsoft products listed at the beginning of this article. Microsoft is researching this problem and will post new information here in the Microsoft Knowledge Base as it becomes available.

MORE INFORMATION

Steps to Reproduce

Start Visual Basic and create a Standard EXE project.. Form1 is created by default.

Add a single TreeView control to Form1.

Add this code to the Form_Click event of Form1:


   Sub Form_Click()
      With TreeView1
         .Nodes.Add , , , "abc"
         .Nodes.Add , , , "def"
         MsgBox .Nodes(1).Root.Text 'returns 'abc'
   MsgBox .Nodes(2).Root.Text 'returns 'abc' also - you expect it
   ' to return 'def'
      End With
   End Sub

Press F5 or select Start from the Run menu to run the application. Observe that both message boxes display the same string.

Additional query words: kbControl kbVBp500bug kbVBp400bug kbVBp kbdsd kbDSupport

Keywords : kbGrpVB
Version :
Platform : NT WINDOWS
Issue type : kbbug