Visual C++ and MFC Programming 2nd Edition

Visual C++ and MFC Fundamentals Chapter 18: Progress-Based Controls

CurPos--;

break;

case SB_LINEDOWN:

if (CurPos < 255)

CurPos++;

break;

case SB_BOTTOM:

CurPos = 255;

break;

case SB_ENDSCROLL:

break;

case SB_THUMBPOSITION:

CurPos = nPos;

break;

case SB_THUMBTRACK:

CurPos = nPos;

break;

}

// Set the new position of the thumb (scroll box).

pScrollBar->SetScrollPos(CurPos);

// Update each color based on the positions of the scroll bar controls

ColorRed = 255 - m_ScrollRed.GetScrollPos();

ColorGreen = 255 - m_ScrollGreen.GetScrollPos();

ColorBlue = 255 - m_ScrollBlue.GetScrollPos();

CDialog::OnVScroll(nSBCode, nPos, pScrollBar);

}

2. Create a timer in the OnInitDialog() event as follows:

SetTimer(1, 40, NULL);

return TRUE; // return TRUE unless you set the focus to a control

}

3. Generate a WM_TIMER message for the dialog box and implement it as follows:

void CPreviewerDlg::OnTimer(UINT nIDEvent)

{

// TODO: Add your message handler code here and/or call default

PaintPreviewArea();

CDialog::OnTimer(nIDEvent);

}

4. Test the application