ScrollBarPict

Private Sub Form_Activate()
'Clip image of picture2 to picture1

ScrollPic Picture2, Picture1, VScroll1
End Sub
'_________________________________________________________

Private Sub Form_Load()
'Setta le proprieta' e la posizione degli oggetti

With Me
.Height = 5000
.Width = 6500
End With
With VScroll1
.Left = 3200
.Top = 200
.Height = 1000
End With
With Picture1
.Left = 200
.Top = 200
.Width = 3000
.Height = 1000
End With
'AutoRedraw deve essere setttato a True!!!

With Picture2
.Left = 200
.Top = 1500
.Width = 3000
.Height = 2500
.Visible = False
End With
'Variabili necessarie

TwipsX = Screen.TwipsPerPixelX
TwipsY = Screen.TwipsPerPixelY
DestPicx = Picture2.Width / TwipsX
DestPicY = Picture2.Height / TwipsY
VScroll1.Max = Picture2.Height / TwipsY - Picture1.Height / TwipsY
'Scrive da A a L sulla Picture2

Dim i As Integer
For i = 0 To 11
Picture2.Print Chr$(65 + i)
Next i
End Sub
'_________________________________________________________

Private Sub VScroll1_Change()
ScrollPic Picture2, Picture1, VScroll1
End Sub

'_________________________________________________________

Private Sub VScroll1_Scroll()
ScrollPic Picture2, Picture1, VScroll1
End Sub
'_________________________________________________________

'3. Aggiungete un modulo con il seguente codice:

Declare Function BitBlt Lib "gdi32" _
(ByVal hDestDC As Integer, ByVal x As Integer, _
ByVal y As Integer, ByVal nWidth As Integer, _
ByVal nHeight As Integer, ByVal hSrcDC As Integer, _
ByVal xSrc As Integer, ByVal ySrc As Integer, _
ByVal dwRop As Long) As Integer
Public Const SRCCOPY = &HCC0020
Public Const SRCAND = &H8800C6
Public Const SRCINVERT = &H660046
Public TwipsX As Long
Public TwipsY As Long
Public DestPicx As Long
Public DestPicY As Long
'_________________________________________________________

Public Sub ScrollPic(SourcePic As Object, _
DestPic As Object, Scroll As Object)
BitBlt DestPic.hDC, 0&, 0&, DestPicx, DestPicY, _
SourcePic.hDC, 0&, Scroll.Value, SRCCOPY
End Sub

Molti programmatori hanno problemi con le Pictureboxes
e le barre di scorrimento. Ecco una soluzione per
questo problema:

1. Aggiungete alla Form1: due pictureboxes (Picture1,
Picture2) ed una barra di scorrimento verticale
(VScroll1). La posizione non importa, gli oggetti
sono posizionati automaticamente dal programma.
C'e' solo una proprieta' che deve essere settata
durante il progetto: AutoRedraw = True della Picture2
(e' molto importante)!

2. Aggiungete il codice seguente alla Form1