[VB6] - controlling a VB6 standard scrollbar

i have these code for get the scrollbar value property:

Code:

---

Option Explicit

Private PrevWin2 As Long
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 SetWindowLong Lib "user32" Alias "SetWindowLongA" (ByVal hwnd As Long, ByVal nIndex As Long, ByVal dwNewLong As Long) As Long
Private Declare Function CallWindowProc Lib "user32" Alias "CallWindowProcA" (ByVal lpPrevWndFunc As Long, ByVal hwnd As Long, ByVal Msg As Long, ByVal wParam As Long, ByVal lParam As Long) As Long
Private Declare Function SetScrollPos Lib "user32" (ByVal hwnd As Long, ByVal code As Long, ByVal nPos As Long, ByVal fRedraw As Boolean) As Long
Private Declare Function GetScrollPos Lib "user32" (ByVal hwnd As Long, ByVal nBar As Long) As Long

Const SB_HORZ = 0
Const SB_VERT = 1
Const SB_BOTH = 3
Private Const GWL_WNDPROC = (-4)
Public lngWndPicture1 As Long
Public lngWndVerticalScrollBar As Long
Public lngWndHorizontalScrollBar As Long
Public lngWndUserControl As Long

Private Function Proc2(ByVal hwnd As Long, ByVal Msg As Long, ByVal wParam As Long, ByVal lParam As Long) As Long
    Dim s As Long
    s = GetScrollPos(lngWndVerticalScrollBar, 1)
    Debug.Print s
    Proc2 = CallWindowProc(PrevWin2, hwnd, Msg, wParam, lParam)
End Function

Public Sub Hook2(Handle As Long)
    'If PrevWin2 = 0 Then
        PrevWin2 = SetWindowLong(Handle, GWL_WNDPROC, AddressOf Proc2)
    'End If
End Sub

Public Sub Unhook2(Handle As Long)
    'If PrevWin2 Then
        Call SetWindowLong(Handle, GWL_WNDPROC, PrevWin2)
        'PrevWin2 = 0
  ' End If
End Sub

---

and heres how i hook it:

Code:

---

If Ambient.UserMode = False Then
        tmrIDEScrollClick.Enabled = True
        lngWndVerticalScrollBar = ScrollingVertical.hwnd
        Hook2 UserControl.ParentControls(0).hwnd
    End If

---

how the debug value is always zero?
(i just need set and get the property Value on VB6 standard scrollbars)

My guess is that UserControl.ParentControls(0) is not a scrollbar
What does the following return

Code:

---

Debug.Print TypeName(UserControl.ParentControls(0))

---

Also, you are not using the right constants in your call. You'll want to use SB_CTL (Const SB_CTL = 2), not 1. Review the MSDN documentation here

Quote:

---

Originally Posted by LaVolpe

My guess is that UserControl.ParentControls(0) is not a scrollbar
What does the following return

Code:

---

Debug.Print TypeName(UserControl.ParentControls(0))

---

Also, you are not using the right constants in your call. You'll want to use SB_CTL (Const SB_CTL = 2), not 1. Review the MSDN documentation here

---

isn't a scrollbar, that why i use a long variable

Code:

---

Public lngWndVerticalScrollBar As Long

---

but these api functions work with standar vb6 scrollbars?

thanks now works. but i need ask anotherthing:
what scale mode i recive the results (because i recive a very big number)?

ok... now i'm trying changing the scroll Value property, but i see 1 error(not error message):

Code:

---

GetScrollInfo lngWndVerticalScrollBar, 2, SI
        If SI.nPos + 10 > SI.nMax Then
            SetScrollPos lngWndVerticalScrollBar, 2, SI.nPos
        Else
            SetScrollPos lngWndVerticalScrollBar, 2, SI.nPos + 10
        End If

---

what i see is that put it on position zero and don't scroll(don't call the change scroll event):(
what can you advice me?

i found my problem:

Code:

---

SI.cbSize = Len(SI)
        SI.fMask = SIF_ALL
        FlatSB_GetScrollInfo lngWndVerticalScrollBar, SB_CTL, SI
        If SI.nPos - ScrollValue < SI.nMin Then
            SI.nPos = SI.nMin
        Else
            SI.nPos = SI.nPos - ScrollValue
        End If
        FlatSB_SetScrollInfo lngWndVerticalScrollBar, SB_CTL, SI, True

---

now the pos button is moved normaly. but why the scrollbar change event isn't called?