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Q248416: FIX: Wrong TreeView Node Selected When SingleSel Property = True

Article: Q248416
Product(s): Microsoft Visual Basic for Windows
Version(s): 6.0
Operating System(s): 
Keyword(s): kbCtrl kbTreeView kbVBp kbVBp600bug kbGrpDSVB kbDSupport kbVS600sp4fix kbVS600sp5fix
Last Modified: 26-JUL-2001

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The information in this article applies to:

- Microsoft Visual Basic Professional Edition for Windows, version 6.0 
- Microsoft Visual Basic Enterprise Edition for Windows, version 6.0 
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SYMPTOMS
========

When using the Microsoft Visual Basic 6.0 service pack 3 (SP3) version of the
TreeView Control, in a project with the SingleSel property set to True, when you
click a node sometimes a different node will be selected and expanded.

RESOLUTION
==========

To work around the problem set the SingleSel property to False and implement the
SingleSel functionality with your code.

STATUS
======

Microsoft has confirmed this to be a bug in the Microsoft products listed at the
beginning of this article. This bug was corrected in the latest service pack for
Visual Studio 6.0.

For additional information about Visual Studio service packs, click the article
numbers below to view the articles in the Microsoft Knowledge Base:

  Q194022 INFO: Visual Studio 6.0 Service Packs, What, Where, Why

  Q194295 HOWTO: Tell That a Visual Studio Service Pack Is Installed

You can download the latest Visual Studio service pack from the following
Microsoft Web site:

  Visual Studio Product Updates
  (http://msdn.microsoft.com/vstudio/downloads/updates.asp)

MORE INFORMATION
================

Steps to Reproduce Behavior
---------------------------

1. Create a new Visual Basic 6.0 SP3 Standard EXE project. Form1 is created by
  default.

2. On the Project menu, select Components. In the Components dialog box, select
  "Microsoft Windows Common Control 6.0(SP3)" and then click OK.

3. Add a TreeView control to Form1, retaining the default name, Treeview1.

4. Add the following code to the General Declarations section of Form1:

  Option Explicit

  Const CHILD1 = "Child1"
  Const CHILD2 = "Child2"
  Const CHILD3 = "Child3"

  Private Sub Form_Load()
     Dim strRoot As String
     Dim strChild As String
     Dim i As Long
     
     ' Set Treeview control properties.
     TreeView1.LineStyle = tvwRootLines  ' Linestyle 1
     TreeView1.SingleSel = True  ' Single Selection
     
     ' populate the treeview control
     For i = Asc("A") To Asc("Z")
        strRoot = Chr(i)
        Call TreeView1.Nodes.Add(, , strRoot, "Root-" & strRoot)

        Call TreeView1.Nodes.Add(strRoot, tvwChild, strRoot & "1", CHILD1)
        Call TreeView1.Nodes.Add(strRoot, tvwChild, strRoot & "2", CHILD2)
        Call TreeView1.Nodes.Add(strRoot, tvwChild, strRoot & "3", CHILD3)

        strChild = strRoot & "1"
        Call TreeView1.Nodes.Add(strChild, tvwChild, strChild & "1", CHILD1)
        Call TreeView1.Nodes.Add(strChild, tvwChild, strChild & "2", CHILD2)
        Call TreeView1.Nodes.Add(strChild, tvwChild, strChild & "3", CHILD3)

        strChild = strRoot & "2"
        Call TreeView1.Nodes.Add(strChild, tvwChild, strChild & "1", CHILD1)
        Call TreeView1.Nodes.Add(strChild, tvwChild, strChild & "2", CHILD2)
        Call TreeView1.Nodes.Add(strChild, tvwChild, strChild & "3", CHILD3)

        strChild = strRoot & "3"
        Call TreeView1.Nodes.Add(strChild, tvwChild, strChild & "1", CHILD1)
        Call TreeView1.Nodes.Add(strChild, tvwChild, strChild & "2", CHILD2)
        Call TreeView1.Nodes.Add(strChild, tvwChild, strChild & "3", CHILD3)
     Next
  End Sub

5. Run the application by pressing F5. Select a child of "Root-A" in the third
  level.

6. Select "Root-I". Note that "Root-L" is selected and expanded instead of
  "Root-I". This behavior is incorrect.

Steps to Work Around the Problem
--------------------------------

1. In the Form_Load() sub, replace the following line:

     TreeView1.SingleSel = True  ' Single Selection

with

     TreeView1.SingleSel = False  ' Not Single Selection

2. Append the following code to the General Declarations section of Form1:

  Private Sub TreeView1_NodeClick(ByVal node As MSComctlLib.node)
     Call SimulateSingleSel(node)
  End Sub

  Private Sub SimulateSingleSel(ByVal node As MSComctlLib.node)
     ' expand current node
     node.Expanded = True

     ' collapse all siblings and parents' siblings
     Dim nodeParent As MSComctlLib.node
     Set nodeParent = node
     Do Until nodeParent Is Nothing
        CollapseSiblings nodeParent
        Set nodeParent = nodeParent.Parent
     Loop

     ' collapse child's siblings (collapse all children)
     Dim nodeChild As MSComctlLib.node

     Set nodeChild = node.Child
     If nodeChild Is Nothing Then Exit Sub
     nodeChild.Expanded = False
     Call CollapseSiblings(nodeChild)
  End Sub

  Private Sub CollapseSiblings(ByVal node As MSComctlLib.node)
     Dim n As Integer

     n = node.FirstSibling.Index
     If n <> node.Index Then node.FirstSibling.Expanded = False
     
     Do While n <> node.LastSibling.Index
        n = TreeView1.Nodes(n).Next.Index
        If n <> node.Index Then TreeView1.Nodes(n).Expanded = False
     Loop
  End Sub

3. Run the application by pressing F5. It now works as expected.

Additional query words: sp4

======================================================================
Keywords          : kbCtrl kbTreeView kbVBp kbVBp600bug kbGrpDSVB kbDSupport kbVS600sp4fix kbVS600sp5fix 
Technology        : kbVBSearch kbAudDeveloper kbZNotKeyword6 kbZNotKeyword2 kbVB600Search kbVB600
Version           : :6.0
Issue type        : kbbug
Solution Type     : kbfix

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