How to offset the vertical position of a item selected in the listbox

  • Thread starter Thread starter Paul
  • Start date Start date
P

Paul

How to offset the vertical position of a item selected in the listbox to the
first row (not the first row in the entire recordset, but the first row in
the listbox)? Which listBox property I should use? Thanks.
 
http://www.lebans.com/List_Combo.htm#ScrollListbox


Scroll a ListBox to a specific row. Emulates the VB ListBox TopIndex
property. You can alter the code to easily have the selected row display
as the first or last row as well. The example code is placed behind a
Command Button.

' *** CODE START
Private Sub cmdListIndex_Click()
On Error GoTo Err_cmdListIndex_Click

' Always make NumRows an odd number
' if you want selected Row to be in the
' middle of the ListBox.

' NumRows is the number of completely visible rows in the ListBox Const
NumRows = 7
' Row we want displayed in middle of ListBox.
Dim intDesiredRow As Integer

' Arbitrarily select the 24th row.
intDesiredRow = 24
' ListBox must have the Focus
Me.List2.SetFocus
' Force ListBox to start from the top
Me.List2.ListIndex = 1

' Force the Scroll offset we desire
Me.List2.ListIndex = intDesiredRow + (NumRows / 2)
' Now select the row without further scrolling
Me.List2.ListIndex = intDesiredRow

Exit_cmdListIndex_Click:
Exit Sub

Err_cmdListIndex_Click:
MsgBox Err.Description
Resume Exit_cmdListIndex_Click

End Sub
' ***CODE END


Method #2

Here's the code to force a ListBox to Scroll to a specific row. I put it
behind a Command Button Named Customer, you can obviously do
whatever you want. Really should be a Class Wrapper for a ListBox to
expose a TopIndex property like VB ListBoxes.

' ***CODE START
'Place this code in the General Declarations of your Form
Private Declare Function SendMessage Lib "user32" Alias "SendMessageA" _
(ByVal hWnd As Long, ByVal wMsg As Long, _
ByVal wParam As Long, lParam As Any) As Long

Private Declare Function GetFocus Lib "user32" () As Long

' Windows Message Constant
Private Const WM_VSCROLL = &H115
' Scroll Bar Commands
Private Const SB_THUMBPOSITION = 4
' Code end for General Declarations


' Code for Control's Click Event
Private Sub Customer_Click()

Dim hWndSB As Long
Dim lngRet As Long
Dim lngIndex As Long
Dim LngThumb As Long

' You will get lngIndex value from the user or whatever.
' For now I'm just setting it to arbitrary Number
lngIndex = 45

' SetFocus to our listBox so that we can
' get its hWnd
Me.List2.SetFocus
hWndSB = GetFocus

' Set the window's ScrollBar position
LngThumb = MakeDWord(SB_THUMBPOSITION, CInt(LngIndex))
lngRet = SendMessage(hWndSB, WM_VSCROLL, LngThumb, 0&)

End Sub

' Here's the MakeDWord function from the MS KB
Function MakeDWord(loword As Integer, hiword As Integer) As Long
MakeDWord = (hiword * &H10000) Or (loword And &HFFFF&) End Function
'***END CODE




--

HTH
Stephen Lebans
http://www.lebans.com
Access Code, Tips and Tricks
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