Advanced MFC Programming

Chapter 2. Menu
CDC *ptrDC;
CDC dcMem;
CBitmap *ptrBmpOld;
CBitmap *ptrBmp;
CRect rect;
if(!(lpDrawItemStruct->CtlType & ODT_MENU))
{
CMenu::DrawItem(lpDrawItemStruct);
return;
}
ptrDC=CDC::FromHandle(lpDrawItemStruct->hDC);
dcMem.CreateCompatibleDC(ptrDC);
if(lpDrawItemStruct->itemState & ODS_SELECTED)
{
switch(lpDrawItemStruct->itemData)
{
case MENUTYPE_SMILE:
{
ptrBmp=&m_bmpSmileSel;
break;
}
case MENUTYPE_QUESTION:
{
ptrBmp=&m_bmpQuestionSel;
break;
}
}
}
else
{
switch(lpDrawItemStruct->itemData)
{
case MENUTYPE_SMILE:
{
ptrBmp=&m_bmpSmile;
break;
}
case MENUTYPE_QUESTION:
{
ptrBmp=&m_bmpQuestion;
break;
}
}
}
}
ptrBmpOld=dcMem.SelectObject(ptrBmp);
rect=lpDrawItemStruct->rcItem;
ptrDC->BitBlt
(
rect.left,
rect.top,
rect.Width(),
rect.Height(),
&dcMem,
0,
0,
SRCCOPY
);
dcMem.SelectObject(ptrBmpOld);
First, we check if the item is a menu. If not, we call the same function implemented by the base class
and return. If so, first we obtain a CDC type pointer to the target device by calling function
CDC::FromHandle(…). Then, we create a compatible memory DC with target DC, which will be used to
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