CScrollBar doesn't work!

[Hossein]

Hi there,I want to scroll an image in a CView window and
I have not (and do not want to) use CScrollView .I mean I
want do the scrolling with CScrollBar control.I have done
the work but it doesn't scroll.When I drag the scroll,it
goes back in its first position .Any suggestion?
I have initializd the control in this way:

scroll.Create(SBS_VERT|WS_CHILD,r,this,100);
scroll.SetScrollRange(0,b.bmHeight);
scroll.SetScrollPos(0);
scroll.ShowScrollBar();

where ,scroll is a CScrollBar inside CView class.
please help me.

 

[Dragoon]

What I have had to do is handle the ON_HSCROLL or ON_VSCROLL messages for the scrollbar. From what I can tell all scrollbars, either dialog controlls you place, or the ones that automatically appear as a part of the view, trigger these messages. When you override the handler the function is this:

OnHScroll(UINT nSBCode, UINT nPos, CScrollBar* pScrollBar)

The first thing you want to do is checkthat the pScrollBar passed into this function is the scrollbar you want to work with. In your case a simple

 if (&scroll == pScrollBar)

will work.

The nSBCode is what action was performed on the scroll bar, and you can alter the position by processing that code, and using the SetScrollPos() function.

I would recommend checking out the MSDN help on the OnHScroll/OnVScroll functions to get all the different nSBCodes, its pretty good.

Dragoon.