LPARAM - worked example

key : purple - original code / blue - new code

Step 1 :

Continue with the program names.

Step 2 :

Edit the AddNameToListCtrl() function within the ListCtrl. The LPARAM feature must be activated :

void CNameListView::AddNameToListCtrl(CName * pNameTemp)
{

CListCtrl& m_listCtrl = GetListCtrl();

LV_ITEM listItem;
listItem.mask = LVIF_PARAM | LVIF_TEXT | LVIF_IMAGE;
listItem.iSubItem = 0;
listItem.lParam = (LPARAM)pNameTemp;

CString* temp = pNameTemp->GetTitleAddress();

Step 3 :

Now using LPARAM members the code in the other functions can be simplified. Edit the DeleteNameFromList() function :

void CNameListView::DeleteNameFromListCtrl(CObject * pHintTemp)
{

CListCtrl& m_listCtrl = GetListCtrl();
LVFINDINFO findStruct;
findStruct.flags = LVFI_PARAM;
findStruct.lParam = (LPARAM)pHintTemp;

int nTemp = m_listCtrl.FindItem(&findStruct);

m_listCtrl.DeleteItem( m_listCtrl.FindItem(&findStruct) );

m_listCtrl.SetItemState(nTemp, LVIS_SELECTED, LVIS_SELECTED);

}

Step 4 :

The SetNewItem() function may be similarly changed :

void CNameListView::SelectNewItem(CObject *pHintTemp)
{

CListCtrl& m_listCtrl = GetListCtrl();
LVFINDINFO findStruct;
findStruct.flags = LVFI_PARAM;
findStruct.lParam = (LPARAM)pHintTemp;
m_listCtrl.SetItemState(m_listCtrl.FindItem(&findStruct), LVIS_SELECTED,
LVIS_SELECTED);

}

Step 5 :

Add a function which allows editing of the data in the ListCtrl :

void CNameListView::EditNameInListCtrl(CObject *pHintTemp)
{

CListCtrl& m_listCtrl = GetListCtrl();
LVFINDINFO findStruct;
findStruct.flags = LVFI_PARAM;

// this is the item that we want to change
findStruct.lParam = (LPARAM)pHintTemp;

// now change the item text - code similar to Initial function
LV_ITEM editItem;

editItem.iItem = m_listCtrl.FindItem(&findStruct);

CName * pNameTemp = (CName*)pHintTemp;

CString* temp = ((pNameTemp->GetTitleAddress()));

LPTSTR pBufTitle = (LPTSTR) temp->GetBuffer(temp->GetLength());
editItem.pszText = pBufTitle;

temp = ((pNameTemp->GetFirstNameAddress()));
LPTSTR pBufFirstName = (LPTSTR) temp->GetBuffer(temp->GetLength());

temp = ((pNameTemp->GetSecondNameAddress()));
LPTSTR pBufSecondName = (LPTSTR) temp->GetBuffer(temp->GetLength());

if( pNameTemp->GetTitle() == "Mr" ||
pNameTemp->GetTitle() == "Sir")
{

editItem.iImage = 0;

}
else if( pNameTemp->GetTitle() == "Dr" ||
pNameTemp->GetTitle() == "Prof")
{

editItem.iImage = 2;

}
else // 99% certain that they must be female
{

editItem.iImage = 1;

}

// editItem.iItem = m_listCtrl.GetItemCount();
m_listCtrl.InsertItem( &editItem );

// changes the text to the edited text
m_listCtrl.SetItemText( editItem.iItem, 0, pBufTitle );
m_listCtrl.SetItemText( editItem.iItem, 1, pBufFirstName );
m_listCtrl.SetItemText( editItem.iItem, 2, pBufSecondName );
temp->ReleaseBuffer();

}

Click here for the basic exercise

Click here for the source code

Click here to return to menu