ccombobox-class_29.cpp

// CMyComboBox is my owner-drawn combo box derived from CComboBox. This
// example measures an item and sets the height of the item to twice the
// vertical extent of its text. The combo box control was created with
// the following code:
// pmyComboBox->Create(
// WS_CHILD|WS_VISIBLE|WS_BORDER|WS_HSCROLL|WS_VSCROLL|
// CBS_SORT|CBS_OWNERDRAWVARIABLE,
// myRect, pParentWnd, 1);
//
voidCMyComboBox::MeasureItem(LPMEASUREITEMSTRUCT lpMeasureItemStruct)
{
ASSERT(lpMeasureItemStruct->CtlType == ODT_COMBOBOX);

if (lpMeasureItemStruct->itemID != (UINT)-1)
 {
 LPCTSTR lpszText = (LPCTSTR)lpMeasureItemStruct->itemData;
ASSERT(lpszText != NULL);
 CSize sz;
 CDC *pDC = GetDC();

 sz = pDC->GetTextExtent(lpszText);

ReleaseDC(pDC);

 lpMeasureItemStruct->itemHeight = 2 * sz.cy;
 }
}