Problem with Dropdownlist Combo box

Simple Question first What is the Difference between CWnd::CtlColor and CWnd::OnCtlColor?

my real problem is that I am creating a flat combobox for an application with some success. I am able to change the color of text and background and overall appearance by handling WM_PAINT and WM_CTLCOLOR messages but when my Combo box style is set to CBS_DROPDOWMLIST, I cannot change the background color or the Text colot in then Static control display window. anyone has suggestions?

CFlatCombo::OnCtlColor(CDC* pDC, CWnd* pWnd, UINT nCtlColor)
{
pDC->SetTextColor(m_crText);
pDC->SetBkColor(m_crBkColor);
pDC->SetBkMode(TRANSPARENT);

//The value of this brush is set in CFLatCombo::SetBkColor
return m_brBkgnd;
}

CFlatCombo::OnPaint()
{
// Most of the Drawing is omitted
CPaintDC dc(this);
CRect rcCombo;
PAINTSTRUCT ps;
BeginPaint(&ps);

GetClientRect(&rcCombo);

CBrush* pBkBrush = new CBrush(m_crBkColor);
CPen* pBkPen = new CPen(PS_SOLID, 1, RGB(0,0,0));

CBrush* pOldBrush = dc.SelectObject(pBkBrush);
CPen* pOldPen = dc.SelectObject(pBkPen);

dc.Rectangle(rcCombo);

EndPaint(&ps);

dc.SelectObject(pOldBrush);
dc.SelectObject(pOldPen);

delete pBkBrush;
delete pBkPen;
}

Sample code to change the color of static controls: use this code in OnCtrlcolor() function dependiong on your requirement:

//Blue color for a specific control on anytype (say IDC_EDIT2 edit control)
HBRUSH hbrBlue=CreateSolidBrush(RGB(0,0,255));
//to change all statis control colors
if(nCtlColor==CTLCOLOR_STATIC)
{
pDC->SetBkColor(RGB(0,255,0));
return hbrGreen;
}
//To change a specific static control color, first give an unique resource id to that static and use this code
if(pWnd->GetDlgCtrlID()==IDC_STATIC_XYZ)
{
pDC->SetBkColor(RGB(0,0,255));
return hbrBlue;
}

Hope this helps
skpradhan