BUG: TreeView Scroll Bar Does Not Disappear When You Set Scroll Property to False at Run Time

RESOLUTION

1. Open a new Standard EXE project in Visual Basic. Form1 is created by default.
2. On the Project menu, click Components, select the Microsoft Windows Common Controls 6.0 check box, and then click OK.
3. Add a TreeView control (TreeView1) and a CheckBox control (Check1) to Form1.
4. Add the following code to the General Declarations section of Form1:

   Option Explicit
   
   Private Const SB_VERT = 1
   
   Private Declare Function ShowScrollBar Lib "user32" _
       (ByVal hWnd As Long, ByVal wBar As Long, ByVal bShow As Long) As Long
   
   Private Sub Check1_Click()
   ' The reference to CBool is not required but is used to enhance clarity.
       Call ShowScrollBar(TreeView1.hWnd, SB_VERT, CBool(Check1.Value))
   End Sub
   
   Private Sub Form_Load()
       Dim i As Integer
       For i = 1 To 20
           TreeView1.Nodes.Add , , , "Item " & i
       Next i
       Check1.Caption = "Show Scroll Bar"
       Check1.Value = vbChecked
   End Sub
   					

5. Run the code, and notice that a vertical scroll bar appears on the TreeView control.
6. Click Show Scroll Bar, and notice that the scroll bar disappears. Click Show Scroll Bar again, and notice that the scroll bar re-appears.