Re: Memory Allocation problem - C / C++ / MFC Discussion Boards

Re: step through debugging useless in C++

11-Feb-02 18:27

Thanks so much for all your help -- I learned a ton about debugging today and blew through a program that would have kept me up all night last week.

Now I reckon I'll have to find someone else's question and give them a hand. thanks,

tim

How to retrieve the name of the domain on Win NT 4.0?

Chen Venkataraman11-Feb-02 9:59

Chen Venkataraman

11-Feb-02 9:59

How to retrieve the name of the domain under which a NT process is running?

Chen Venkataraman

Re: How to retrieve the name of the domain on Win NT 4.0?

Joaquín M López Muñoz11-Feb-02 10:32

Joaquín M López Muñoz

11-Feb-02 10:32

Seems like

<a href="http://msdn.microsoft.com/library/default.asp?url=/library/en-us/netmgmt/ntlmapi2_07zj.asp">NetWkstaUserGetInfo</a>

is what you're looking for.

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

Re: How to retrieve the name of the domain on Win NT 4.0?

Chen Venkataraman11-Feb-02 10:39

Chen Venkataraman

11-Feb-02 10:39

Thanks.

Chen Venkataraman

Memory Allocation problem

ISIS5511-Feb-02 9:24

ISIS55

11-Feb-02 9:24

I'm working on a map editor for my game and I've ran into some problem. To give you an idea of what's it supposed to do, think of the old game mine-field. Now my program is supposed to put an unlimited number of those mine-objects manually. The number of the 'mines' could range between 0 and 384. The 'mine' is derived from a class.

I solved the problem by defining an array with the maximum of 384 mine-objects, each representing a place in the map. And when I want to actually put the mine I just "activate" it. It works, but it's a waste of a lot of memory because it's 384 mine-objects, 384 prize-objects etc etc. You get the idea.

How can I implement a better way to define new objects at run time? I figured memory allocation would help but how does it work with classes? I only used it for simple arrays not objects that contain various types of variables.

Thanks in advance,

Isaac Sasson,
Small time programmer - complainer at large.
Sonork ID 100.13704

Re: Memory Allocation problem

Joaquín M López Muñoz11-Feb-02 9:41

Joaquín M López Muñoz

11-Feb-02 9:41

You can use STL vector, which works pretty much like the arrays you're used to, with some extra capabilities, like the ability to grow on demand. If your mine objects are instances of a class called (for instance) CMine, then you declare your vector like this:

std::vector<CMine> vectorMines;

Initially, a vector is empty. You can populate it with

vectorMines.push_back(CMine(...));

Elements of a vector are accessed in a way similar to a built-in array:

for(size_t i=0;i<vectorMines.size();++i)
{
  vectorMines[i].draw(); // draw the i-th mine.
}

STL comes wiht other containers (lists, maps) offering different features and trade-offs (random access vs. random erasing, for instance). Look for some STL tutorial on the net and start enjoying this great library.
Regards,

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

Re: Memory Allocation problem

Tim Smith11-Feb-02 9:54

Tim Smith

11-Feb-02 9:54

Functionally, there is little difference between:

main ()
{
    CMine theMines [384];

}

and

main ()
{
    CMine *ptheMines = new CMine [theNumberINeed];
    ... do stuff ...
    delete [] ptheMines;
}

Don't sweat creating an array of the specific number of mines you need after you determine the count.

Tim Smith
Descartes Systems Sciences, Inc.

Re: Memory Allocation problem

ISIS5511-Feb-02 10:40

ISIS55

11-Feb-02 10:40

The problem is I don't know the number of "mines" nor does the user. It's desgined that way you just add mines whenever and wherever you like at run time, it doesn't ask you for the number of "mines" you're going to use.

I used your solution for the game itself when the number is set after reading the level data from a file.
The editor however is a bit different.

Thanks anyway.

Isaac Sasson,
Small time programmer - complainer at large.
Sonork ID 100.13704

CFile::write | create and Windows 2000/XP

mimi11-Feb-02 8:59

mimi

11-Feb-02 8:59

Hello friends !
How are you ?

I need a small help . Please ! Roll eyes | :rolleyes:

Well, I see that CFile::Open with CFile::modeCreate|CFile::modeWrite
When I want to write into the file if it exist and if not to create it works excellent in win98
but on win2000 and XP it success only to create the file if it was not ,and when the file (.dat) already exist it doesn't success to perform modeWrite and should have first to do : CFile::remove()

my question :

1. Why ?
2. How could to do it at the best and elegant way ?
3. Are there a function to know if a specific file exist or not ? which ?

thanks in advance
Wink | ;)

Re: CFile::write | create and Windows 2000/XP

Mazdak11-Feb-02 9:40

Mazdak

11-Feb-02 9:40

mimi wrote:
Are there a function to know if a specific file exist or not ? which ?

Check:CFileFind

Mazy

Don't Marry a Person You Can Live With...
Marry Someone You Can Not Live Without

MANY THANKS !

mimi11-Feb-02 10:15

mimi

11-Feb-02 10:15

I think I found the answer to my second question
perhaps I need to add CFile::modeNoTruncate

Trying to use CFormView in a dialog :o)

Jon Hulatt11-Feb-02 8:28

Jon Hulatt

11-Feb-02 8:28

Hello people.

I'm trying to get a CFormView derived class inside of a dialog. Why? well, i want a small area of my dialog to be kind of a sub dialog, with dynamically created controls in it. CFormView is a nice way to go, cos then i get scroll functionality on this little pane.

Anyway. Trying to add the view like this:

CRect rect(10, 10, 200, 200);
CRuntimeClass* pClass = RUNTIME_CLASS(CMyFormView);
pView = (CMyFormView*)pClass->CreateObject();
pView->Create(NULL, NULL, WS_CHILD, rect, this, AFX_IDW_PANE_FIRST, NULL);
pView->MoveWindow(rect);
pView->ShowWindow(SW_SHOW);

This doesn't work. The compiler generates an error on the pView->Create() line. This is because the Create() member (which comes from the base class) is protected:. but I don't understand why it's protected! it's not in CView, and not in CScrollView.

So what I tried next, was adding a virtual function, Create() to the CMyFormView class. the supplied virtual function calls the base class implementation, using the parameters passed in. ie:

BOOL CMyFormView::Create(LPCTSTR lpszClassName, LPCTSTR lpszWindowName, DWORD dwStyle, const RECT& rect, CWnd* pParentWnd, UINT nID, CCreateContext* pContext) 
{
	// TODO: Add your specialized code here and/or call the base class
	
	return CFormView::Create(lpszClassName, lpszWindowName, dwStyle, rect, pParentWnd, nID, pContext);
}

This seemed a good idea, because the virtual function is allowed to call the protected base class member. However, running the code causes an assert, in the base class create... ie CFormView::Create()...

if (!_AfxCheckDialogTemplate(m_lpszTemplateName, TRUE))
{
    ASSERT(FALSE);          // invalid dialog template name

Something's wrong with the dialog template name. But I thought this was handled by the framework on my behalf? I specified a dialog resource when I created the class, and the enum IDD in the class declaration of my dirived class reflects this. Any clues as to how to get a working CFormView inside a dialog???

Your help will earn you a beer!!!

Thanks

Jon

Sorry to dissapoint you all with my lack of a witty or poignant signature.

Why I now feel like a spanner

Jon Hulatt11-Feb-02 8:30

Jon Hulatt

11-Feb-02 8:30

Immediately after posting that last message, I realised i'd used a regular dialog box template, not a IDD_FORMVIEW type template.

Oh dear, i think it's time to get some sleep.

Sorry to dissapoint you all with my lack of a witty or poignant signature.

CListCtrl report - resizeing columns (resezing same in Outlook 98/2000/2002 - solution !(?) )

Wizard_0111-Feb-02 4:28

Wizard_01

11-Feb-02 4:28

I have problem with style report in the concrete with resizeing columns. I wrote code to autoresize(as resizeing column in Outlook) column but problem is while users changeing width of App (for example CListView in SDI app). During resizeing (because width of column is not changeing at once) users can see horz. scrollbar. Present MS-Outlook - here is same case.

Can I set width of column at once ? Currently I useing function SetItem().

My Code :
HRESULT CDodomuHeaderCtrl::OnLayout(WPARAM wparam,LPARAM lparam){
if (!m_bNowResizeing){
AutoSizeItems();
LPHDLAYOUT lay = (LPHDLAYOUT)lparam;
HRESULT lResult = CHeaderCtrl::DefWindowProc(HDM_LAYOUT, 0, lparam);
return lResult;
}
else {
return NULL;
}
}

void AutoSizeItem(){
... compute new width
m_bNowResizeing = true;
for(....){ // (remark 1)
HDITEM item;
... fill struct
SetItem(i,&item);
}
m_bNowResizeing = false;

}

-----

remark 1. :
Here is greatest problem : If users decrease width of ListCtrl will in moment width of all column >> ( Frown | :-(

) then client area and Windows (CListCtrl) show horz. scrollbar.

Please ... Can you help me ?

Thank VERY MUCH !!!!

Roll eyes | :rolleyes:

Wizard

Re: CListCtrl report - resizeing columns (resezing same in Outlook 98/2000/2002 - solution !(?) )

Joaquín M López Muñoz11-Feb-02 5:07

Joaquín M López Muñoz

11-Feb-02 5:07

Haven't tried it myself, but maybe you can use WM_SETREDRAW to disable automatic redrawing while the resizing is in progress:

void AutoSizeItem(){
... compute new width
SendMessage(WM_SETREDRAW,(WPARAM)FALSE); // disable redrawing
for(....){ 
HDITEM item;
... fill struct
SetItem(i,&item);
}
SendMessage(WM_SETREDRAW,(WPARAM)TRUE); // enable redrawing
}

Let us know if that worked! Regards,

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

Re: CListCtrl report - resizeing columns (resezing same in Outlook 98/2000/2002 - solution !(?) )

Wizard_0111-Feb-02 5:15

Wizard_01

11-Feb-02 5:15

))

Thank you for !!!

Roll eyes | :rolleyes:

Wiizi

how to set default size of propertypage

parag11-Feb-02 3:45

parag

11-Feb-02 3:45

Hi I have a property sheet , within that we have a property page
i want to change the default size of the page
OnInitDialog of page is never called as we just add pages to the sheet
How do we size the page by default ??

parag

Re: how to set default size of propertypage

Joaquín M López Muñoz11-Feb-02 4:26

Joaquín M López Muñoz

11-Feb-02 4:26

By default OnInitDialog is not called when you add a property page to a sheet, but rather the first time the property page is displayed. You can force OnInitDialog to be called when the property sheet is created by setting the flag PSP_PREMATURE in the dwFlags member of the PROPSHEETPAGE structure associated to a property page --note however that this capability is only supported starting from version 4.71 of the common controls library.

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

Why do my radio buttons never appear in Classwizard?

Jon Hulatt11-Feb-02 3:17

Jon Hulatt

11-Feb-02 3:17

All,

Forgive this dumb-assed question...

I want to implement and owner-drawn radio button. If I add a radio button in dialog editor, it's resource id never appears in the member variables tab in ClassWizard.

Why not? Surely I don't have to CMyRButton::Create() on them? there must be a way to use the dialog editor?

Thanks

Jon

Sorry to dissapoint you all with my lack of a witty or poignant signature.

Re: Why do my radio buttons never appear in Classwizard?

Mazdak11-Feb-02 3:32

Mazdak

11-Feb-02 3:32

You mean you put radio button in dialog and check owner draw check box?

Mazy

Don't Marry a Person You Can Live With...
Marry Someone You Can Not Live Without

Re: Why do my radio buttons never appear in Classwizard?

Rickard Andersson²⁰11-Feb-02 3:47

Rickard Andersson²⁰

11-Feb-02 3:47

You have to give all radio controls a unique ID... I think thats the problem... because it's the same thing with ALL static text controls. They have ID IDC_STATIC (I think) and if you change it to IDC_STATIC1 then it will appear in the CW.

------------------------------------
Rickard Andersson, Suza Computing
ICQ#: 50302279
I'm from the winter country SWEDEN!

------------------------------------

Re: Why do my radio buttons never appear in Classwizard?

Jon Hulatt11-Feb-02 4:20

Jon Hulatt

11-Feb-02 4:20

I tried this, having had the same problem with static's in the past. No luck though... they still don't appear.

Sorry to dissapoint you all with my lack of a witty or poignant signature.

Re: Why do my radio buttons never appear in Classwizard?

Nish Nishant11-Feb-02 5:08

Nish Nishant

11-Feb-02 5:08

I tried it and no probs at all.
If you have three radio buttons then check the "group" setting for the first box. Only then will it come in CW

Nish

Nish was here, now Nish has gone;
He left his soul, to turn you on;
Those who knew Nish, knew him well;
Those who didn't, can go to hell.

I like to Jig | [Dance]

on the Code Project

Sonork ID 100.9786 voidmain
www.busterboy.org

Wizards in WinCe?

VanHlebar11-Feb-02 3:00

VanHlebar

11-Feb-02 3:00

Does anyone know if wizards are supported in WinCe? I am attempting to create on my device runing WinCe 3.0 and I am getting an error of SetWizardMode not a member of CWizardSheet, which is my derived class from CPropertySheet.

Just wondering if they are supported or not.

Thanks,
-Eric

Disregard this, after looking in the documentation it clearly states that wizards are not supported in wince.

Visual C++ & OpenGL

Rajveer11-Feb-02 2:42

Rajveer

11-Feb-02 2:42

If I create an MDI application using visual studio, how do I make an openGL child window for the application?

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.