ToolTipListCtrl.cpp

// ToolTipListCtrl.cpp : implementation file
//

#include "stdafx.h"
#include "ToolTipListCtrl.h"

#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

/////////////////////////////////////////////////////////////////////////////
// CToolTipListCtrl

CToolTipListCtrl::CToolTipListCtrl()
{
	m_wHitMask = INITIAL_HITMASK;
}

CToolTipListCtrl::~CToolTipListCtrl()
{
	// Cleanup when destroyed

	DeleteAllToolTips();
}


BEGIN_MESSAGE_MAP(CToolTipListCtrl, CListCtrl)
	//{{AFX_MSG_MAP(CToolTipListCtrl)
		// NOTE - the ClassWizard will add and remove mapping macros here.
	//}}AFX_MSG_MAP

   //Trap all TTN_NEEDTEXT* Messages
   //TTN_NEEDTEXT* messages are sent when a ToolTipCtrl wants a control
   //to provide it with text to display as the tooltip.
   //Specifically, when the TOOLINFO structure passed back to the ToolTipCtrl
   //after ::OnToolHitTest has it's lpszText memeber set to LPSTR_TEXTCALLBACK.

	ON_NOTIFY_EX_RANGE(TTN_NEEDTEXTW, 0, 0xFFFF, OnToolTipText)
	ON_NOTIFY_EX_RANGE(TTN_NEEDTEXTA, 0, 0xFFFF, OnToolTipText)
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CToolTipListCtrl message handlers

int CToolTipListCtrl::OnToolHitTest(CPoint point, TOOLINFO * pTI) const {

   //See if the point falls onto a list item
	//UINT nFlags = 0;

	LVHITTESTINFO lvhitTestInfo;

	lvhitTestInfo.pt	= point;

	int nItem = ListView_SubItemHitTest(
			this->m_hWnd,
			&lvhitTestInfo);
	int nSubItem = lvhitTestInfo.iSubItem;

	UINT nFlags =   lvhitTestInfo.flags;

   //nFlags is 0 if the SubItemHitTest fails
   //Therefore, 0 & <anything> will equal false
   if (nFlags & m_wHitMask){
      //If it did fall on a list item,
      //and it was also hit one of the
      //item specific sub-areas we wish to show tool tips for

      //Get the client (area occupied by this control
      RECT rcClient;
      GetClientRect( &rcClient );

      //Fill in the TOOLINFO structure
      pTI->hwnd = m_hWnd;
      pTI->uId = (UINT) (nItem * 100 + nSubItem);
      pTI->lpszText = LPSTR_TEXTCALLBACK;
      pTI->rect = rcClient;

      return (int)pTI->uId; //By returning a unique value per listItem,
                       //we ensure that when the mouse moves over another list item,
                       //the tooltip will change
   }else{
      //Otherwise, we aren't interested, so let the message propagate
      return -1;
   }
}

BOOL CToolTipListCtrl::OnToolTipText( UINT id, NMHDR * pNMHDR, LRESULT * pResult ){
	//Handle both ANSI and UNICODE versions of the message
	TOOLTIPTEXTA* pTTTA = (TOOLTIPTEXTA*)pNMHDR;
	TOOLTIPTEXTW* pTTTW = (TOOLTIPTEXTW*)pNMHDR;

	//Ignore messages from the built in tooltip, we are processing them internally
	if( (pNMHDR->idFrom == (UINT)m_hWnd) &&
		 ( ((pNMHDR->code == TTN_NEEDTEXTA) && (pTTTA->uFlags & TTF_IDISHWND)) ||
         ((pNMHDR->code == TTN_NEEDTEXTW) && (pTTTW->uFlags & TTF_IDISHWND)) ) ){
      return FALSE;
   }


   *pResult = 0;

	CString strTipText;

	//Get the mouse position
	const MSG* pMessage;
   pMessage = GetCurrentMessage();
	ASSERT ( pMessage );
   CPoint pt;
   pt = pMessage->pt; //Get the point from the message
	ScreenToClient( &pt ); //Convert the point's coords to be relative to this control

   //See if the point falls onto a list item

	LVHITTESTINFO lvhitTestInfo;

	lvhitTestInfo.pt	= pt;

	int nItem = SubItemHitTest(&lvhitTestInfo);
	int nSubItem = lvhitTestInfo.iSubItem;

	UINT nFlags =   lvhitTestInfo.flags;

   //nFlags is 0 if the SubItemHitTest fails
   //Therefore, 0 & <anything> will equal false
   if( nFlags & m_wHitMask ){
	  //If it did fall on a list item,
      //and it was also hit one of the
      //item specific sub-areas we wish to show tool tips for

      //Lookup the list item's text in the ToolTip Map

	  CString strKey;

	  strKey.Format(_T("%d"),  nItem * 100 + nSubItem);

      if( m_ToolTipMap.Lookup(strKey, strTipText ) ){
         //If there was a CString associated with the list item,
         //copy it's text (up to 80 characters worth, limitation of the TOOLTIPTEXT structure)
         //into the TOOLTIPTEXT structure's szText member

         //Deal with UNICODE
      #ifndef _UNICODE
	      if (pNMHDR->code == TTN_NEEDTEXTA)
		      lstrcpyn(pTTTA->szText, strTipText, 80);
	      else
		      _mbstowcsz(pTTTW->szText, strTipText, 80);
      #else
	      if (pNMHDR->code == TTN_NEEDTEXTA)
		      _wcstombsz(pTTTA->szText, strTipText, 80);
	      else
		      lstrcpyn(pTTTW->szText, strTipText, 80);
      #endif
         return TRUE;    //We found a tool tip,
                         //tell the framework this message has been handled

////////////////////////////////////////////////////////////////////////////////
// ****** Special note *****
//
// Still don't understand why the function must return FALSE for CListCtrl
// so as not to cause flickering, as opposed to Nate Maynard's derivation
// from CTreeCtrl.
// I have experimented with disabling Tooltips for the control
// and found out that a "ghost" tooltip appears for a fraction of a second...
//
// I am completely at a loss...
// Seems to work, though...
//
////////////////////////////////////////////////////////////////////////////////
							
      }
   }

   return FALSE; //We didn't handle the message,
                 //let the framework continue propagating the message
}

//Sets the tooltip text for a specific item
BOOL CToolTipListCtrl::SetItemToolTipText( int nItem, int nSubItem, LPCTSTR lpszToolTipText ){

  CString strKey;

  strKey.Format(_T("%d"),  nItem * 100 + nSubItem);

  m_ToolTipMap.SetAt( strKey, lpszToolTipText );

  return TRUE;

}

//Retrieve the tooltip text for a specific list item
CString CToolTipListCtrl::GetItemToolTipText( int nItem, int nSubItem){

  CString itemToolTipText;

  CString strKey;

  strKey.Format(_T("%d"),  nItem * 100 + nSubItem);


  if( !m_ToolTipMap.Lookup( strKey, itemToolTipText ) ){
     itemToolTipText = "";
  }

  return itemToolTipText;
}


WORD CToolTipListCtrl::SetToolTipHitMask( WORD wHitMask ){
   WORD oldHitMask = m_wHitMask;

   m_wHitMask = wHitMask;

   return oldHitMask;
}

void CToolTipListCtrl::DeleteAllToolTips()
{
   m_ToolTipMap.RemoveAll();
}

BOOL CToolTipListCtrl::DeleteAllItems( ){
	//Call the base class method
	BOOL retVal = CListCtrl::DeleteAllItems();

	if( retVal ){
		//If it succeeded, remove all tooltips
		  DeleteAllToolTips();
	}

	return retVal;
}

BOOL CToolTipListCtrl::DeleteItem( int nItem ){

    //Call the base class method
    BOOL retVal = CListCtrl::DeleteItem( nItem );

    if( retVal ){
		//If it succeeded, remove it's tooltip from the map

		LVCOLUMN *lvColumn = (LVCOLUMN*) malloc (sizeof(LVCOLUMN));

		int i;
		for (i = 0; GetColumn(i, lvColumn) != 0; i++);
		{
			CString strKey;

			strKey.Format(_T("%d"),  nItem * 100 + i);

			m_ToolTipMap.RemoveKey( strKey );
		}
    }

	return retVal;
}