CListCtrl missing LVN_ROWCLICK

MICHAEL@datatree.com
Monday, June 03, 1996

Environment: VC++ 4.1 and Windows 95

The CListCtrl class has a notification message
called LVN_COLUMNCLICK.Why no LVN_ROWCLICK?

Because of this omission, there is no simple
way to detect user clicks on a row. I'm left
wondering if my only choice is to to use the
LVN_ITEMCHANGED instead - ugh!

This notification message can occur multiple
times for a given "row click".
------------------------------
Michael L. Thal
Data Tree Corporation
voice: (619) 231-3300
fax:   (619) 231-3301

---

MICHAEL@datatree.com
Monday, June 10, 1996

I was able to solve this myself, so I'll post
the solution for general consumption.

 Using HitTest() is much better than handling
LVN_ITEMCHANGED notifications to detect
which row has been selected in a CListCtrl.

Also, I can more easily process right clicks,
left clicks and double clicks in a CListCtrl.
(See the notifications NM_CLICK, NM_RCLICK
and NM_DBCLK.)

Here is sample code for processing a single
click in a CListCtrl row.

MYVIEW.H
--------
class CMyView : public CView
CListCtrl m_ListCtrl;

MYVIEW.CPP
----------
LRESULT CMyView::NotifyHandler(UINT, WPARAM wParam, LPARAM lParam) 
{
    LV_HITTESTINFO lvHitTestInfo;
    POINT pt;
    LV_DISPINFO *pLvdi = (LV_DISPINFO *)lParam;
    
    if (wParam != ID_LISTVIEW)
        return (LRESULT)0;

    switch(pLvdi->hdr.code)
    {

        case NM_CLICK:
            ::GetCursorPos((LPPOINT)&pt);
            ::ScreenToClient(m_ListCtrl.m_hWnd, &pt);
             lvHitTestInfo.pt = pt;
             m_ListCtrl.HitTest(&lvHitTestInfo);
 
            // iItem is the index into the CListCtrl row
            if (lvHitTestInfo.iItem != -1)
            {
                // Do nothing - this is samle code
                MessageBeep(0);
            }
            break;

        default:
            break;
    }
    return (LRESULT)0;
}

Note: My app only allows single selections,
as I added the LVS_SINGLESEL to my Create()
function. 

>
>Michael L. Thal wrote:
>> The CListCtrl class has a notification message
>> called LVN_COLUMNCLICK.Why no LVN_ROWCLICK?
>> 
>> Because of this omission, there is no simple
>> way to detect user clicks on a row. I'm left
>> wondering if my only choice is to to use the
>> LVN_ITEMCHANGED instead - ugh!
>> 
>> This notification message can occur multiple
>> times for a given "row click".
>
>


>Environment: VC++ 4.1 and Windows 95
>
>The CListCtrl class has a notification message
>called LVN_COLUMNCLICK.Why no LVN_ROWCLICK?
>
>Because of this omission, there is no simple
>way to detect user clicks on a row. I'm left
>wondering if my only choice is to to use the
>LVN_ITEMCHANGED instead - ugh!
>
>This notification message can occur multiple
>times for a given "row click".
------------------------------
Michael L. Thal
Data Tree Corporation
voice: (619) 231-3300
fax:      (619) 231-3301

---

Roger Onslow -- Roger_Onslow@compsys.com.au
Tuesday, June 11, 1996

[Mini-digest: 3 responses]

>Environment: VC++ 4.1 and Windows 95
>
>The CListCtrl class has a notification message
>called LVN_COLUMNCLICK.Why no LVN_ROWCLICK?
>
>Because of this omission, there is no simple
>way to detect user clicks on a row. I'm left
>wondering if my only choice is to to use the
>LVN_ITEMCHANGED instead - ugh!
>
>This notification message can occur multiple
>times for a given "row click".

LVN_COLUMNCLICK is for when you click on a
column heading (this is the hook to do sorting
by a given column).

LButton click will (usually) select the given row
so you can simply get the selected item. (in
the handler for the click after calling the base
class which should do the selection for you).

Roger


-----From: Alex Sevugan 

Hi guys,

There is an easier way to do this, i think. Call the function GetNextItem to 
get the index of the current row.

     m_ListCtrl.GetNextItem(-1,LVNI_SELECTED)
     
     returns the index of the currently selected row.

Alaks
CSC Intelicom


-----From: "Gary MacDougall" 

[Moderator's note: Please, when you have new questions, ask them
in a new thread.  I have a habit of terminating threads when I
feel the original question has been answered.]

Hi,

On a related note with CListCtrl's.  I have a sort of dilema.  I want
to be able to select a single row in the CListCtrl and have it select
the corresponding columns of that row (like a list box).  How can
this be done? I basically wanna treat every row in the ListCtrl, like
a line in a list box (i.e. Return the row selected when the HITTEST is
done for anywhere in the row...).

Thanks,
Gary

---

Kevin_L_McCarthy.IACNET@ngate.zis.ziff.com
Wednesday, June 12, 1996

>Hi,
>
>On a related note with CListCtrl's.  I have a sort of dilema.  I want
>to be able to select a single row in the CListCtrl and have it select
>the corresponding columns of that row (like a list box).  How can
>this be done? I basically wanna treat every row in the ListCtrl, like
>a line in a list box (i.e. Return the row selected when the HITTEST is
>done for anywhere in the row...).
>
>Thanks,
>Gary

VC 4.1 has a sample called ROWLIST which draws the selection highlight 
over the entire row, and, I think, allows you to select a row by clicking 
anywhere
within it.

Kevin

---

| Вернуться в корень Архива |