Windows CE-禁用CComboBox高亮

Question

I'm using Visual Studio 2008 to write an application for Windows CE 6 using C++ and MFC.

I want to remove the blue highlight of a CComboBox derived class when I've selected an element. According to this MSDN article , I cannot set the style of the combo box to LBS_OWNERDRAWFIXED or CBS_OWNERDRAWFIXED to choose the color of the selection on my DrawItem function.

I've tried to use the message CBN_SELCHANGE to send a WM_KILLFOCUS message. It partially work : the control loose its focus (the selected element is not blue anymore), but if I click again the combo box, it didnt show the list of elements.

I've read that I can use the paint event to set the color of the highlight, but I didn't know or find how to do this.

How can I remove the blue highlight of the combo box?

Edit: the combobox is read-only (flag CBS_DROPDOWNLIST)

Answer 1

I've found a (dirty) workaroud, in case nobody give a better approach :

I set a parent when I create the combobox :

customCombo.Create(WS_CHILD | WS_VISIBLE | WS_TABSTOP | CBS_DROPDOWNLIST | CBS_DROPDOWN, CRect(0, 0, 0, 0), **PARENT**, COMBO_ID);

The following lines give the focus to the parent element when I'm done using the combo box.

In CComboBox subclass header file :

public:
    afx_msg void OnCbnSelchange();
    afx_msg void OnCbnSelendcancel();
    afx_msg void OnCbnSelendok();

In source file :

void CustomCombo::OnCbnSelchange() {
    //give focus to parent
    CWnd* cwnd = GetParent();
    if (cwnd != NULL) {
        cwnd->SetFocus();
    }
}


void CustomCombo::OnCbnSelendcancel() {
    //give focus to parent
    CWnd* cwnd = GetParent();
    if (cwnd != NULL) {
        cwnd->SetFocus();
    }
}

void CustomCombo::OnCbnSelendok() {
    //give focus to parent
    CWnd* cwnd = GetParent();
    if (cwnd != NULL) {
        cwnd->SetFocus();
    }
}

Answer 2

In your header:

public:
virtual void DrawItem(LPDRAWITEMSTRUCT lpDrawItemStruct);

and in cpp:

void CYourComboBox::DrawItem(LPDRAWITEMSTRUCT lpDrawItemStruct) 
{
// TODO: Add your code to draw the specified item
CDC* pDC = CDC::FromHandle (lpDrawItemStruct->hDC);

if (((LONG)(lpDrawItemStruct->itemID) >= 0) &&
    (lpDrawItemStruct->itemAction & (ODA_DRAWENTIRE | ODA_SELECT)))
{
    // color item as you wish
}

if ((lpDrawItemStruct->itemAction & ODA_FOCUS) != 0)
    pDC->DrawFocusRect(&lpDrawItemStruct->rcItem);

}

the model are taken from here:

Extended combobox