This menu is another modification of owner draw menus (#2 if you want to know). I have
corrected an error I found (use of uninitialized variable in DrawItem), change item measurement
(now the height is the bigger from icon height or menu height) and changed the menu concept from
using separate icons for each item to use of image list (CImageList) so all the icons are in one
bitmap. For more information see original article by Ben Ashley
What’s new
- Icon size is not determined every time it’s needed but is stored in member variables
- Fixed few unnecesary lines of code
What to use them ?
To be able to use owner draw popup menu items it is neccesary to add following to the main window class:
In the message map:
ON_WM_MEASUREITEM()
In the declaration (header) file:
afx_msg void OnMeasureItem(int nIDCtl, LPMEASUREITEMSTRUCT lpMeasureItemStruct);
And in the definition (source) file:
static CMenu* FindPopupMenuFromID(CMenu* pMenu, UINT nID)
{
ASSERT_VALID(pMenu);
// walk through all items, looking for ID match
UINT nItems = pMenu->GetMenuItemCount();
for (int iItem = 0; iItem < (int)nItems; iItem++) { CMenu* pPopup = pMenu->GetSubMenu(iItem);
if (pPopup != NULL)
{
// recurse to child popup
pPopup = FindPopupMenuFromID(pPopup, nID);
// check popups on this popup
if (pPopup != NULL)
return pPopup;
}
else if (pMenu->GetMenuItemID(iItem) == nID || (UINT)pMenu->GetSafeHmenu() == nID)
{
// it is a normal item inside our popup
pMenu = CMenu::FromHandlePermanent(pMenu->m_hMenu);
return pMenu;
}
}
// not found
return NULL;
}void CMainWnd::OnMeasureItem(int nIDCtl, LPMEASUREITEMSTRUCT lpMeasureItemStruct)
{
if (lpMeasureItemStruct->CtlType == ODT_MENU)
{
ASSERT(lpMeasureItemStruct->CtlID == 0);
CMenu* pMenu;_AFX_THREAD_STATE* pThreadState = AfxGetThreadState();
if (pThreadState->m_hTrackingWindow == m_hWnd)
{
// start from popup
pMenu = CMenu::FromHandle(pThreadState->m_hTrackingMenu);
}
else
{
// start from menubar
pMenu = GetMenu();
}pMenu = FindPopupMenuFromID(pMenu, lpMeasureItemStruct->itemID);
if (pMenu != NULL)
pMenu->MeasureItem(lpMeasureItemStruct);
else
TRACE1(“Warning: unknown WM_MEASUREITEM for menu item 0x%04X.n”, lpMeasureItemStruct->itemID);
}
else
{
CWnd* pChild = GetDescendantWindow(lpMeasureItemStruct->CtlID, TRUE);
if (pChild != NULL && pChild->SendChildNotifyLastMsg())
return; // eaten by child
}
// not handled – do default
Default();
}
Last updated on: August 27, 1998.
