c++ - 如何去除MFC中弹出菜单的边框

Question

我有从类继承的自定义CMenu类。我正在尝试更改菜单项的背景颜色。但菜单项的边框保持不变。以下是我的重写功能：

void CNewMenu::MeasureItem(LPMEASUREITEMSTRUCT lpMeasureItemStruct)
{
    lpMeasureItemStruct->itemHeight = 100;
    lpMeasureItemStruct->itemWidth = 150;
}

void CNewMenu::DrawItem(LPDRAWITEMSTRUCT lpDrawItemStruct)
{
    CRect rectFull(lpDrawItemStruct->rcItem); 
    COLORREF TextRect = COLORREF(RGB(0, 0, 0)); 
    CDC* pDC = CDC::FromHandle(lpDrawItemStruct->hDC);
    pDC->FillSolidRect(&rectFull, TextRect);
    pDC->TextOut(rectFull.left, rectFull.top, ((MenuObject*)lpDrawItemStruct->itemData)->m_strCaption);
}

如何删除边框或更改边框颜色？

我指的是弹出菜单周围的灰色边框