[CListCtrl]顯示單個儲存格之Tip

一樣內容也是臨時找的，並沒有整理，一定會雷同。

這邊需自行處理訊息，所以要加入兩個訊息
    ON_NOTIFY_EX_RANGE(TTN_NEEDTEXTW, 0, 0xFFFF, OnToolTipText)
    ON_NOTIFY_EX_RANGE(TTN_NEEDTEXTA, 0, 0xFFFF, OnToolTipText)

然後也需要改寫CListCtrl::OnToolHitTest()，裡面是用來設定UID，用途目前不明，但缺少的話，tip會閃一下就消失了。

 int CXListCtrl::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_wHistMask){  
//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 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;  
}  
}  

再來就是上面自己定義的Function，tip所要顯示的文字就在這這裡面設定：

 BOOL CXListCtrl::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_wHistMask ){  
//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);  
lstrcpyn(pTTTA->szText, "AAA", 80);  
else  
//_mbstowcsz(pTTTW->szText, strTipText, 80);  
_mbstowcsz(pTTTW->szText, "Double Click Me", 80);  
#else  
if (pNMHDR->code == TTN_NEEDTEXTA)  
_wcstombsz(pTTTA->szText, strTipText, 80);  
else  
lstrcpyn(pTTTW->szText, strTipText, 80);  
#endif  
return FALSE;  //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,  
}  

Reference:Handling TTN_NEEDTEXT Notification for Tool Tips