How to make a ListView scroll...why doesn't this work?

VB Code:
  1. Private Declare Function SendMessage Lib "user32" _
  2. Alias "SendMessageA" (ByVal hwnd As Long, ByVal wMsg As _
  3. Long, ByVal wParam As Long, lParam As Any) As Long
  4.  
  5. Const SB_LINEDOWN = 1
  6. Const SB_LINEUP = 0
  7. Const SB_PAGEDOWN = 3
  8. Const WM_VSCROLL = &H2E
  9.  
  10. Private Sub Command1_Click()
  11.   SendMessage ListView1.hwnd, WM_VSCROLL, SB_LINEDOWN, 0&
  12. End Sub