Changing the tool tip as the mouse pointer moves along different tree control items is fairly simple. The tree control can be on a dialog, property page or a form view. Assuming that you use a class derived from CFormView called CMyFormView, which has a tree control, the steps to follow are:

1. Declare a member variable for the tree control (IDC_TREE1), m_tree.
2. Decide on how the tip for each tree item will be stored. For instance, you could hold the tip in a map which you declare in the header file CMyFormView.h.
   

   	CMap< HTREEITEM,HTREEITEM&,CString,CString& > tooltipMap;

3. Fill the map as you generate the items of the tree. For instance after every InsertItem:

   	HTREEITEM hItem = m_tree.InsertItem(&tvItem); // tvItem is of type TV_INSERTSTRUCT
   	tooltipMap[hItem] = " Tool Tip Text   ";   // Set the tool tip text of the item.
   	

4. Declare an object of CToolTipCtrl in the header file CMyFormView .h

   	CToolTipCtrl m_tooltip;

5. Create the tool tip control and initialize it in the OnInitialUpdate message handler (OnInitDialog for CDialog derived classes)

   	m_tooltip.Create(this);
   	m_tooltip.Activate(TRUE);
   	m_tooltip.AddTool(GetDlgItem(IDC_TREE1), "Tree Tool Tip");
   

6. Override the PreTranslateMessage in the form view.

   	BOOL CMyFormView::PreTranslateMessage(MSG* pMsg)
   	{
   		// TODO: Add your specialized code here and/or call the base class
   		if(pMsg->message == WM_MOUSEMOVE && pMsg->hwnd == m_tree.m_hWnd)
   		{
   		CPoint point(LOWORD(pMsg->lParam),HIWORD(pMsg->lParam));
   			HTREEITEM hItem = m_tree.HitTest(point);
   			if(hItem != NULL)
   			{
   				CString text = tooltipMap[hItem];
   				m_tooltip.UpdateTipText(text,&m_tree);
   				m_tooltip.RelayEvent(pMsg);
   			}
   
   		}
   	}
   	

   This changes the tool tip text as the mouse pointer moves along the different items in the tree control.

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