Selecting items in the list - worked example

key : purple - original code / blue - new code

Step 1 :

Continue with the program names.

Step 2 :

Edit the MoveCurrentBack() (and MoveCurrentForward()) functions by adding the following hint :

void CNamesDoc::MoveCurrentBack()
{

if( !m_NameList.IsEmpty() )
{

m_NameList.GetPrev(m_nCurrentPosition);

if( m_nCurrentPosition == NULL )
{

AfxMessageBox("End of list reached");
m_nCurrentPosition = m_NameList.GetHeadPosition();

}
CName * pCurrentName = m_NameList.GetAt(m_nCurrentPosition);
UpdateAllViews(NULL, HINT_MOVE_CURRENT, pCurrentName);

}
else
{

AfxMessageBox("There are no items in the list.");

}

}

Step 3 :

Edit the OnUpdate() function to call a new function on this hint :

void CNameListView::OnUpdate(CView* pSender, LPARAM lHint, CObject* pHint)
{

CListCtrl& listCtrl = GetListCtrl(); // Get list ctrl

CName * pName = (CName *)pHint;

long messageType = (long)lHint;

switch (lHint)
{

case HINT_DELETE_ALL_NAMES:
//do not need seperate function as just one line of code
listCtrl.DeleteAllItems();
break;

case HINT_ADD_NAME:
AddNameToListCtrl(pName);
break;

case HINT_DELETE_NAME:
DeleteNameFromListCtrl(pName);
break;

case HINT_MOVE_CURRENT:
SelectNewItem(pName);
break;

}

}

Step 4 :

Add the function SelectNewItem(pName). LVIS_SELECTED is of type UINT and signifies that it is the selected item that has changed :

void CNameListView::SelectNewItem(CName *pNameTemp)
{

CListCtrl& m_listCtrl = GetListCtrl();

LV_ITEM listItem;
listItem.mask = LVIF_TEXT | LVIF_IMAGE;
listItem.iSubItem = 0;

CString strtempTitle = (pNameTemp->GetTitle());
CString strtempFirstName = (pNameTemp->GetFirstName());
CString strtempSecondName = (pNameTemp->GetSecondName());

for( int nItem = 0; nItem < m_listCtrl.GetItemCount(); nItem++)
{

if(strtempTitle == m_listCtrl.GetItemText(nItem, 0) &&
strtempFirstName == m_listCtrl.GetItemText(nItem, 1) &&
strtempSecondName == m_listCtrl.GetItemText(nItem, 2))

{

m_listCtrl.SetItemState(nItem, LVIS_SELECTED,
LVIS_SELECTED)

}

}

}

Step 5 :

Add a Windows Message Handler to the NameListView. This creates the function OnItemChanged(). The if statements check that all of the states are correct.

void CNameListView::OnItemChanged(NMHDR* pNMHDR, LRESULT* pResult)
{

NM_LISTVIEW* pNMListView = (NM_LISTVIEW*)pNMHDR;
CListCtrl& m_listCtrl = GetListCtrl();

// TODO: Add your control notification handler code here

if( pNMListView->uChanged & LVIF_STATE )
{

if(!( pNMListView->uOldState & LVIS_SELECTED))
{

if( pNMListView->uNewState & LVIS_SELECTED)
{

LV_ITEM listItem;
listItem.mask = LVIF_TEXT | LVIF_IMAGE;
CString strTitle = m_listCtrl.GetItemText(pNMListView->iItem, 0);
CString strFirstName = m_listCtrl.GetItemText(pNMListView->iItem, 1);
CString strSecondName = m_listCtrl.GetItemText(pNMListView->iItem, 2);

CNamesDoc* pDoc = (CNamesDoc*)m_pDocument;
pDoc->ChangeToNewCurrent(strTitle, strFirstName, strSecondName);

*pResult = 0;

}

}

}

}

Step 6 :

Add the ChangeToNewCurrent() function to the Document :

void CNamesDoc::ChangeToNewCurrent(CString strTitle,
CString strFirstName, CString strSecondName)
{

m_nCurrentPosition = GetHeadPosition();
POSITION pos = m_nCurrentPosition;

while(pos!=NULL)
{

CName * pNameTemp = m_NameList.GetAt(pos);
if( pNameTemp->GetTitle()== strTitle &&
pNameTemp->GetFirstName() == strFirstName &&
pNameTemp->GetSecondName() == strSecondName )
{

m_nCurrentPosition = pos;

}

m_NameList.GetNext(pos);
}

UpdateAllViews(NULL);

}

Click here for the basic exercise

Click here for the source code

Click here to return to menu