Add a ListBox and make its visible property to False.


'Add this code to the form declaration

Option Explicit
Dim intColIdx As Integer
 'This will contain the index for the current  cell in the dbgrid
Dim blnListShow As Boolean 'is the list showing or not


Private Sub DBGrid1_ButtonClick(ByVal ColIndex As Integer)
Dim intTop As Integer
   intColIdx = ColIndex
   If blnListShow = False Then 'if the list is not showing then...
      blnListShow = True
      List1.Left = DBGrid1.Columns(ColIndex).Left + 360
      intTop = DBGrid1.Top + (DBGrid1.RowHeight * (DBGrid1.Row +2))
      List1.Top = intTop
      List1.Width = DBGrid1.Columns(ColIndex).Width + 15
      List1.Visible = True
      List1.SetFocus
   Else 'if the list is show, hide it
      blnListShow = False
      List1.Visible = False
   End If
End Sub


Private Sub Form_Load()
   blnListShow = False 'initialize
End Sub

Private Sub List1_Click()
   DBGrid1.Columns(intColIdx).Text = List1.Text
   'set the value of the dbgrid
   List1.Visible = False 'hide the list
End Sub

Private Sub List1_LostFocus()
   blnListShow = False
   List1.Visible = False
End Sub