MFC Scrollbar example

#include <afxwin.h>

#define ID_SCROLLBAR 1000
#define ID_STATIC    1001

class CSimpleApp : public CWinApp
{
public:
    BOOL InitInstance();
};

class CMainFrame : public CFrameWnd
{
public:
    CMainFrame();

    afx_msg void SetLabel(int);
    afx_msg void OnHScroll(UINT nSBCode, UINT nPos, CScrollBar* pScrollBar);

    DECLARE_MESSAGE_MAP()

    CScrollBar wScrollbar;
    CStatic wStatic;
};

BOOL CSimpleApp::InitInstance()
{
    m_pMainWnd = new CMainFrame();
    m_pMainWnd->ShowWindow(m_nCmdShow);
    return TRUE;
}

CMainFrame::CMainFrame()
{
    Create(NULL,
           _T("MFC Scrollbar Example"),
           WS_OVERLAPPEDWINDOW,
           CRect(25, 25, 450, 170));

    // Create static control
    wStatic.Create(_T(""),
                   WS_CHILD | WS_VISIBLE | WS_BORDER,
                   CRect(25, 60, 75, 90),
                   this,
                   ID_STATIC);

    // Create horizontal scrollbar
    wScrollbar.Create(WS_CHILD | WS_VISIBLE | SBS_HORZ,
                      CRect(10, 10, 410, 50),
                      this,
                      ID_SCROLLBAR);

    // Set scrollbar range and initial position
    wScrollbar.SetScrollRange(0, 100, TRUE);
    wScrollbar.SetScrollPos(0);

    SetLabel(0);
}

BEGIN_MESSAGE_MAP(CMainFrame, CFrameWnd)
    ON_WM_HSCROLL()
END_MESSAGE_MAP()

CSimpleApp MFCApp1;

// Handles horizontal scrollbar messages
afx_msg void CMainFrame::OnHScroll(UINT nSBCode,
                                   UINT nPos,
                                   CScrollBar* pScrollBar)
{
    int minpos;
    int maxpos;

    pScrollBar->GetScrollRange(&minpos, &maxpos);

    int curpos = pScrollBar->GetScrollPos();

    switch (nSBCode)
    {
        case SB_LEFT:             // Scroll to minimum position
            curpos = minpos;
            break;

        case SB_RIGHT:            // Scroll to maximum position
            curpos = maxpos;
            break;

        case SB_ENDSCROLL:        // End of scrolling
            break;

        case SB_LINELEFT:         // Scroll one line left
            curpos--;
            break;

        case SB_LINERIGHT:        // Scroll one line right
            curpos++;
            break;

        case SB_PAGELEFT:         // Scroll one page left
            curpos -= 5;
            break;

        case SB_PAGERIGHT:        // Scroll one page right
            curpos += 5;
            break;

        case SB_THUMBPOSITION:    // Thumb released
            curpos = nPos;
            break;

        case SB_THUMBTRACK:       // Thumb being dragged
            curpos = nPos;
            break;
    }

    // Keep position within the valid range
    if (curpos < minpos)
        curpos = minpos;

    if (curpos > maxpos)
        curpos = maxpos;

    pScrollBar->SetScrollPos(curpos);

    SetLabel(curpos);

    CFrameWnd::OnHScroll(nSBCode, nPos, pScrollBar);
}

// Display scrollbar position in the static control
afx_msg void CMainFrame::SetLabel(int newvalue)
{
    CString text;
    text.Format(_T("%d"), newvalue);
    wStatic.SetWindowText(text);
}