C / C++ / MFC

7-Mar-06 7:43

Okay so I created a dialog box with a List Control in it. I am trying to
get the index of the current item selected in order to retrieve the text and
use it in a map. I found examples here but for some reason I am not getting
an index number back. All I get is 0.

Heres the code:

<br />
std::map<std::string, int>mpCalibrations;<br />
<br />
********<br />
<br />
for(i=0;i<=74;i++){<br />
  LvItem.iItem=i;<br />
  LvItem.iSubItem=1;<br />
  sprintf(Temp,"%d",mpCalibrations[calibrate_list[i]]);<br />
  LvItem.pszText=Temp;<br />
  SendMessage(hList,LVM_SETITEM,0,(LPARAM)&LvItem); <br />
/******/<br />
<br />
case WM_NOTIFY:{<br />
 switch(LOWORD(wParam)){<br />
  case IDC_LIST2:{<br />
  int iSlected=0;<br />
  int lResult=0;<br />
  if(((LPNMHDR)lParam)->code == NM_CLICK){<br />
    iSlected=SendMessage(hList,LVM_GETNEXTITEM,-1,LVNI_FOCUSED);<br />

Please help..

TY

-- modified at 13:47 Tuesday 7th March, 2006

David Crow7-Mar-06 8:33

7-Mar-06 8:33

How about:

int nItem = SendMessage(hList, LVM_GETNEXTITEM, -1, LVNI_SELECTED);
assert(nItem >= 0);
LVITEM lvi = {0};
char szTemp[128];
lvi.mask       = LVIF_TEXT;
lvi.pszText    = szTemp;
lvi.cchTextMax = sizeof(szTemp);
SendMessage(hList, LVM_GETITEMTEXT, nItem, (LPARAM) &lvi);

"Let us be thankful for the fools. But for them the rest of us could not succeed." - Mark Twain

"There is no death, only a change of worlds." - Native American Proverb

Greg Barnes7-Mar-06 9:05

7-Mar-06 9:05

Well, I still got a 0 back for nItem. I cannot see what the problem is.
Any other ideas???

David Crow7-Mar-06 9:14

7-Mar-06 9:14

At the time this code is executed, is there a selected item in the control?

"Let us be thankful for the fools. But for them the rest of us could not succeed." - Mark Twain

"There is no death, only a change of worlds." - Native American Proverb

Greg Barnes7-Mar-06 9:58

7-Mar-06 9:58

In debug mode(.NET), the value remains 0. Furthermore, I initialized the
value to 5 and it is being SET to 0. The final app, will allow you to select
an item and via the map, display the corresponding value in an EditBox for
modifying. I added this code to confirm that I'm getting 0 no matter what
I select.
The map is filled w/ random numbers for now.

<br />
if(((LPNMHDR)lParam)->code == NM_CLICK){<br />
  int nItem = SendMessage(hList, <br />
           LVM_GETNEXTITEM, <br />
           -1, <br />
            LVNI_SELECTED);<br />
  SendMessage(hList, <br />
            LVM_GETITEMTEXT, <br />
            nItem, <br />
            (LPARAM) &lvi);:confused:<br />
  itoa(nItem,buffer,4);<br />
  SetWindowText(hwndEdit,buffer);<br />
}

David Crow7-Mar-06 10:29

7-Mar-06 10:29

When you click a button to execute this code snippet, the list control will lose focus, and perhaps deselect any items that had been selected. Does the control have the LVS_SHOWSELALWAYS style?

What does this return:

int nCount = SendMessage(hList, LVM_GETSELECTEDCOUNT, 0, 0);

Remember that items in the control are 0-based.

"Let us be thankful for the fools. But for them the rest of us could not succeed." - Mark Twain

"There is no death, only a change of worlds." - Native American Proverb

James R. Twine7-Mar-06 10:30

James R. Twine

7-Mar-06 10:30

   Getting back 0 from LVM_GETNEXTITEM is a valid return, not an error return; -1 is an error return (or "not items found"). Getting back 0 indicates that the first (zero-ith) item in the control is selected.

   Calling SendMessage again with the same parameters will return zero again because you are still specifying -1 for the "start" of the search.

   Peace!

-=- James

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Greg Barnes7-Mar-06 11:03

7-Mar-06 11:03

A bit more code:

<br />
case WM_INITDIALOG:{<br />
 HWND hList=GetDlgItem(hwnd,IDC_LIST2);<br />
 SendMessage(hList,<br />
             LVM_SETEXTENDEDLISTVIEWSTYLE,<br />
	     0,<br />
             LVS_EX_FULLROWSELECT | LVS_SHOWSELALWAYS); <br />

Well David, I tried this snippet and a big fat 0. Frown | :(

I initialized it to 500.

<br />
 nCount = SendMessage(hList, LVM_GETSELECTEDCOUNT, 0, 0);<br />
 itoa(nCount,buffer,10);<br />
 SetWindowText(hwndEdit,buffer);<br />

James, my understanding is the above "SendMessage" will return the index
of the item selected. I'm selecting in the middle of my 75 item list.
Shouldn't it return a value the same as "GETCURSEL" does for a listbox???
This was so easy with a regular ListBox.(ughhhh)

I'm probably gonna be beating my head against the wall once the solution is
discovered. Something simple I'm sure... WTF | :WTF:

Critical sections

hint_547-Mar-06 7:42

hint_54

7-Mar-06 7:42

What are they? Any good tutorial about it?

Regards [[]]

hint_54

Re: Critical sections

Joe Woodbury7-Mar-06 8:15

Joe Woodbury

7-Mar-06 8:15

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dllproc/base/critical_section_objects.asp[^]

Anyone who thinks he has a better idea of what's good for people than people do is a swine.
- P.J. O'Rourke

mktime()

DanYELL7-Mar-06 6:58

DanYELL

7-Mar-06 6:58

I am super stuck and very frustrated. I have a simple date time control.
If I put in a date from 1970 on, everything works fine. If I put in a
date that is less than or includes 1969, the program crashes at the bottom
on the ASSERT line which is the last line of this code:

CTime::CTime(int nYear, int nMonth, int nDay, int nHour, int nMin, int nSec,
int nDST)
{
struct tm atm;
atm.tm_sec = nSec;
atm.tm_min = nMin;
atm.tm_hour = nHour;
ASSERT(nDay >= 1 && nDay <= 31);
atm.tm_mday = nDay;
ASSERT(nMonth >= 1 && nMonth <= 12);
atm.tm_mon = nMonth - 1; // tm_mon is 0 based
ASSERT(nYear >= 1900);
atm.tm_year = nYear - 1900; // tm_year is 1900 based
atm.tm_isdst = nDST;
m_time = mktime(&atm);
ASSERT(m_time != -1); // indicates an illegal input time
}

Looking at the call stack, the input is:

CTime::CTime(int 1960, int 6, int 3, int 0, int 0, int 0, int -1)

I tried changing the nDST to 0 or 1 and that doesnt stop the error from
coming.

Any ideas? Any chance I can email someone a small sample project that
keeps displaying this error?

Please, any response any one can give me will be greatly appreciated.

Sincerely,
Danielle Brina (an overworked graduate student)

Re: mktime()

David Crow7-Mar-06 7:06

7-Mar-06 7:06

DanYELL wrote:
If I put in a
date that is less than or includes 1969, the program crashes at the bottom
on the ASSERT...

A crash is vastly different than an assertion. You canot use a value any earlier than midnight, January 1970.

"Let us be thankful for the fools. But for them the rest of us could not succeed." - Mark Twain

"There is no death, only a change of worlds." - Native American Proverb

Re: mktime()

DanYELL7-Mar-06 7:10

DanYELL

7-Mar-06 7:10

Its an assertion error in the timecore.cpp file (line 40). I did
alittle more research on the web and found:

// If timeptr references a date before midnight,
// January 1, 1970, or if the calendar time cannot be
// represented, mktime returns –1 cast to type time_t.

I cant believe I cant use a value earlier than 1970. Isnt there a
work around somehow? Im trying to prompt for the persons date of
birth which in this case is in the 1960's. Is there any way to use
a date before 1970?

Please, any response any one can give me will be greatly appreciated.

Sincerely,
Danielle Brina (an overworked graduate student)

Re: mktime()

David Crow7-Mar-06 7:16