Visual C++ and MFC Programming 2nd Edition

Chapter 17: Track-Based Controls Visual C++ and MFC Fundamentals

12. To set the starting color of the preview picture, access the OnPain() event of the
    CcolorPreviewDlg class and change it as follows:

void CColorPreviewDlg::OnPaint()

{

CPaintDC dc(this); // device context for painting

CRect RectPreview;

CBrush BrushGray(PreviewColor);

m_Preview.GetWindowRect(&RectPreview);

CBrush *pOldBrush = dc.SelectObject(&BrushGray);

ScreenToClient(&RectPreview);

dc.Rectangle(RectPreview);

dc.SelectObject(pOldBrush);

if (IsIconic())

{

SendMessage(WM_ICONERASEBKGND,

reinterpret_cast<WPARAM>(dc.GetSafeHdc()), 0);

// Center icon in client rectangle

int cxIcon = GetSystemMetrics(SM_CXICON);

int cyIcon = GetSystemMetrics(SM_CYICON);

CRect rect;

GetClientRect(&rect);

int x = (rect.Width() - cxIcon + 1) / 2;

int y = (rect.Height() - cyIcon + 1) / 2;

// Draw the icon

dc.DrawIcon(x, y, m_hIcon);

}

else

{

CDialog::OnPaint();

}

}

13. Test the application and return to MSVC

17.1.2..Creating a Spin Button.......................................................................

To create a spin button, at design time, you can click the Spin button on the Controls

toolbox and click the desired area on the intended host.

A spin button control is based on the CSpinButtonCtrl class. Therefore, to

programmatically create a spin button, declare a pointer to CSpinButtonCtrl then call its

Create() method to initialize it. The syntax of the CSpinButtonCtrl::Create() method

is:

BOOL Create( DWORD dwStyle, const RECT& rect, CWnd* pParentWnd, UINT nID );

Because a spin button cannot be a parent, the minimum style you must apply is

WS_CHILD. If you want the control to be visible upon creating, add the WS_VISIBLE

style. Here is an example: