How to make checkbox background transparent?

i use the following code to make check box background trans开发者_如何学Pythonparent or in my case off white but i can't find what wrong with this plz help me how to do this?

HBRUSH CfvcolorDlg::OnCtlColor(CDC* pDC, CWnd* pWnd, UINT nCtlColor)
{
 HBRUSH hbr = CDialog::OnCtlColor(pDC, pWnd, nCtlColor);

 pDC->SetBkColor(MYCOLOR);

 if((HBRUSH)brush == NULL)
    brush.CreateSolidBrush(MYCOLOR);
 return (HBRUSH) brush;
}  

where is 'brush' declared? As you posted it it won't even compile.