Scroll to specific list box entry

  • Thread starter Thread starter Guest
  • Start date Start date
G

Guest

I am trying to scroll to a specific line entry in a multi-select list box in
response to a user-input search criterion (in a separate text box) so that
the desired record becomes visible to the user. I can locate the matching
record and determine the line number, but I can't find a VBA method to scroll
to reposition the record.

My intent is to enable a user to enter the beginning character(s) to locate
the section of entries that begin with the user search criterion. From that
position, the user can then select the entries of choice.

I will appreciate any help.

Richard
 
Here are two methods:

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
Please respond only to the newsgroups so everyone can benefit.
 
Thank you, Stephen, for your very prompt response. Your response resolved my
question. It was very clear, specific, and thorough. Thanks again.
 
Back
Top