deleting double pointers - C / C++ / MFC Discussion Boards

Antony M Kancidrowski13-Oct-04 8:51

13-Oct-04 8:51

otrcomm wrote:
Could it be that I turned off precompiled headers

No, If you have sections of code that rarely change then it is advisable to turn on precompiled headers. Basically they speed up compilation as the compiler does not need to compile all code each time you compile. (You do need to compile it all at least once however!) It is not necessary to have precompiled headers turned on.

otrcomm wrote:
The RedrawWindow() command did work, but it does seem like additional overhead.

Basically what you are doing here is ensuring that the list is redrawn before the code continues to execute. If you do not do this then paint messages are normally processed when the code comes to a natural break.

You may also be able to ease the problem by running the SQL code in another thread (leaving the main thread to process the paint messages) the choice is yours.

Ant.

I'm hard, yet soft.
I'm coloured, yet clear.
I'm fruity and sweet.
I'm jelly, what am I? Muse on it further, I shall return! - David Williams (Little Britain)

Re: CListBox AddString Question/Problem

otrcomm13-Oct-04 11:20

otrcomm

13-Oct-04 11:20

Hello,

Thanks again!

Since I am just testing the CppSQLite code too understand it better, I don't mind the overhead of the RedrawWindow() command now. However, under production code, I will take your advice and create a separate thread for the SQL code.

Another question. When you reply to my messages, I see parts of my message included. What setting at CodeProject do you have turned on to include the message you are replying too? I just get a blank textbox to reply in.

Thanks,
Murrah Boswell

Re: CListBox AddString Question/Problem

Antony M Kancidrowski13-Oct-04 11:37

Antony M Kancidrowski

13-Oct-04 11:37

otrcomm wrote:
When you reply to my messages

If you look at the text you are replying to, just underneath it is a button "Quote Selected Text". If you highlight the text and press the button it quotes it in the text of the reply.

In this case I highlighted "When you reply to my messages" and pressed the button.

Ant.

I'm hard, yet soft.
I'm coloured, yet clear.
I'm fruity and sweet.
I'm jelly, what am I? Muse on it further, I shall return! - David Williams (Little Britain)

Image Editor

Vini Deep12-Oct-04 20:38

Vini Deep

12-Oct-04 20:38

Hi all,
Does anybody know how image editors are made.I dont mean the image manipulation part ,but the canvas like thing we see in ms paint on which we draw ,erase .draw lines etc....I dont think it is a dilog.It would rather be a window , a paint window but how do we maintain it.say loading am image to a window is simple and i prefer the IPicture and IStream way of the win32 sdk.Once the image is loaded ,i even managed to draw on it ,like using moveto and line functions from the gdi.But the real trouble is how would i store the image temporarily.Say i have the image read from the file into the IStream and enclosed by IPicture .I render this from the IPicture to the window.Now i draw some lines over the image.Technically the dc is modified.Now how would i extract this modified dc into a buffer and latter on store it to a file.One suitable way is to Create a compatible dc and bitmap make a snapshot of this window,but it is not good,the image is not clear .How would i go around this situation.

Please help.

Vini

Help Needed (Toolbar)

Avinash Gupta12-Oct-04 20:28

Avinash Gupta

12-Oct-04 20:28

Hi,
How can I make a toolbar having buttons, which toggles their state from pressed to un pressed and vice versa like the toolbar of MS Paints?

Re: Help Needed (Toolbar)

Cedric Moonen12-Oct-04 20:49

Cedric Moonen

12-Oct-04 20:49

Take a look at PressButton from CToolBarCtrl.

help needed....Creating a 3D graph at the end of execution...

Kiran Satish12-Oct-04 19:25

Kiran Satish

12-Oct-04 19:25

Hi,

I have a program which generates a 2D data and i want to plot it into a 3D surface Plot at the end of the execution of my program.

at present i am writing it into a text file and then i am importing it inot excel file to plot the 3D graph... i would like to have tht 3D graph to be viewed in my program itself....( my prorgam is a plain cpp file...and I am running it in VC++, i think i have to convert it into ActiveX file... but I am not familiar with it)

anyone plz help me on this....hhow to proceed

thanks in advance,

Suman

deleting double pointers

Majid Shahabfar12-Oct-04 19:23

Majid Shahabfar

12-Oct-04 19:23

struct GroupConstant<br />
{<br />
CString** grpConst;<br />
};<br />
<br />
GroupConstant** m_pGrpConst;<br />
<br />
m_pGrpConst = new GroupConstant*[200];<br />
for(BYTE i=0 ; i<200 ; i++)<br />
m_pGrpConst[i] = new GroupConstant[50];<br />
<br />
CString** pstr = new CString*[4];<br />
for(BYTE i=0 ; i<4 ; i++)<br />
pstr[i] = new CString[2];<br />
<br />
<br />
GroupConstant** ppTemp = m_pGrpConst;<br />
GroupConstant* pTemp = (*m_pGrpConst);<br />
<br />
for(i=0 ; i<200 ; i++)<br />
{<br />
for(BYTE j=0 ; j<50 ; j++)<br />
{<br />
(*m_pGrpConst)->grpConst = pstr;<br />
(*m_pGrpConst)++;<br />
}<br />
(*m_pGrpConst) = pTemp;<br />
}<br />
m_pGrpConst = ppTemp;<br />

I have two double pointers. one is a content of the structure and other is pointer to the structure.
I initiate these double pointers as you see in the code. but now I have a problem with deleting these pointes.
how can I delete the double pointer included with structure and double pointer points to structur.
Thank you in advance.

How to solve this Problem?

pubududilena12-Oct-04 18:34

pubududilena

12-Oct-04 18:34

hi all,
I have created MFC Program.But when I compilled it ,I got such a Error:-
"fatal error C1189: #error : include 'stdafx.h' before including this file for PCH"
Can anybody please tell me how to correct that Problem Frown | :(

??

Thanks in advance..

Re: How to solve this Problem?

Ryan Binns12-Oct-04 18:48

Ryan Binns

12-Oct-04 18:48

Put #include "stdafx.h" at the top of the .cpp file that causes the error.

Ryan

"Punctuality is only a virtue for those who aren't smart enough to think of good excuses for being late" John Nichol "Point Of Impact"

Re: How to solve this Problem?

pubududilena12-Oct-04 19:06

pubududilena

12-Oct-04 19:06

hi,
yes ..it is already in the top of the .Cpp file.But the Problem is appearing yet.
------This is the header file :------------------
// rtcsample.h : main header file for the RTCSAMPLE application
//
#if _MSC_VER > 1000
#pragma once
#endif // _MSC_VER > 1000

#ifndef __AFXWIN_H__
#error include 'stdafx.h' before including this file for PCH
#endif

#include "resource.h" // main symbols

class CRtcsampleApp : public CWinApp
{
public:
CRtcsampleApp();
public:
virtual BOOL InitInstance();
};

This the .Cpp file-------------------------------------------
// rtcsample.cpp : Defines the entry point for the application.
include "stdafx.h"
// WinMain
//
int APIENTRY WinMain(HINSTANCE hInstance,
HINSTANCE hPrevInstance,
LPSTR lpCmdLine,
int nCmdShow)
{
HRESULT hr;
UNREFERENCED_PAR
//extra code here
}

Can you tell me how to correct it?
OR
Is there a Problem in "stdafx.h" File?

Re: How to solve this Problem?

Michael Dunn12-Oct-04 20:19

Michael Dunn

12-Oct-04 20:19

See the FAQ: http://www.codeproject.com/cpp/cppforumfaq.asp#cl_nopch[^]

--Mike--
Personal stuff:: Ericahist | Homepage
Shareware stuff:: 1ClickPicGrabber | RightClick-Encrypt
CP stuff:: CP SearchBar v2.0.2 | C++ Forum FAQ
----
Wizard needs food, badly!

How to put a progress in my project ?

King of Merit12-Oct-04 16:57

King of Merit

12-Oct-04 16:57

Hi,
In my project, I want to upgrade my application (there is a class named CUpgradeApplication in my project) by retrieving a file from web. And when the file was loading, I want to put a download progress but I don't know how to do.
Please help me.
Thank you very much.

Re: How to put a progress in my project ?

Sujan Christo12-Oct-04 18:19

Sujan Christo

12-Oct-04 18:19

Hi,
Have a look @ this article http://www.codeguru.com/Cpp/I-N/internet/filetransfer/article.php/c6235/[^]
Sujan

Re: How to put a progress in my project ?

ThatsAlok12-Oct-04 18:45

ThatsAlok

12-Oct-04 18:45

see The api UrlFiletoDownload or see article by mr Micheal Dunn in internet section overe this api

-----------------------------
"I Think It Will Help"
-----------------------------
Alok Gupta
visit me at http://www.thisisalok.tk

What does "const vector& vars" mean?

Rafferty Uy12-Oct-04 16:11

Rafferty Uy

12-Oct-04 16:11

Hello there,

I have been tracing a C++ code and I encountered a declaration statement like this:

const vector<int>& vars

Can anyone teach me what this is and how it is used? Smile | :)

I tried searching for references on this and I was not able to find any.

Thanks so much!

-Rafferty

Re: What does "const vector& vars" mean?

Ryan Binns12-Oct-04 18:07

Ryan Binns

12-Oct-04 18:07

Rafferty Uy wrote:
const vector<int>& vars

This is a reference to a constant template vector class that has been specialised with int as its template parameter, ie. it's a reference to a constant variable-length array of ints.

Ryan

"Punctuality is only a virtue for those who aren't smart enough to think of good excuses for being late" John Nichol "Point Of Impact"

Re: What does "const vector& vars" mean?

Rafferty Uy12-Oct-04 20:41

Rafferty Uy

12-Oct-04 20:41

I see... could you give me an example on how to use this? or even a link to a reference will do. Sorry I really don't have an idea of this yet. I don't even know what a template in C++ is. Smile | :)

Thanks!

Rafferty

Re: What does "const vector& vars" mean?

Ryan Binns13-Oct-04 1:59

Ryan Binns

13-Oct-04 1:59

I don't know of any tutorials off the top of my head. I recommend you get a good C++ book that includes a section on templates, or google for a C++ template tutorial (or both Wink | ;)

)

Ryan

"Punctuality is only a virtue for those who aren't smart enough to think of good excuses for being late" John Nichol "Point Of Impact"

File access rights

Anonymous12-Oct-04 16:04

Anonymous

12-Oct-04 16:04

Hi,

Can I rename/delete a file another process has open?

Thank you,

Re: File access rights

Ryan Binns12-Oct-04 18:12

Ryan Binns

12-Oct-04 18:12

Anonymous wrote:
Can I rename/delete a file another process has open?

Simple answer: No

Complex answer: You can't while it's open. You can use MoveFileEx() to delay the rename/delete until the next reboot, and let Windows do it for you at startup.

Ryan

"Punctuality is only a virtue for those who aren't smart enough to think of good excuses for being late" John Nichol "Point Of Impact"

Re: File access rights

Sudhir Mangla12-Oct-04 18:34

Sudhir Mangla

12-Oct-04 18:34

You should check if the file is open or not before trying these operations

Sudhir Mangla

http://Programmerworld.net

(Free books , articles and Source Code)

CString undeclared?!

jadegal12-Oct-04 13:38

jadegal

12-Oct-04 13:38

I was following some online examples on creating a
simple user form in visual c++, and I just came upon a
strange thing...that is, after putting in teh text
boxes and radio buttons etc, we go to put in a button
for the user to click, then according to the online
instructions, by double clicking on that button it
should take me to the code section where I can then
define what I want the form to do...but I just
noticed that in doing so, it takes me to the .h and
not .cpp file to define the code! That is kind of
strange..shouldn't I define my codes in the .cpp
file?

Also, when I try to put in additional logics, such as
declaring CString variables to do stuff with it, it
tells me CString is not declared...this is really
strange...

any assistance would be greatly
appreciated...

thank you!

Re: CString undeclared?!

Christian Graus12-Oct-04 13:55

Christian Graus

12-Oct-04 13:55

You're using MFC, right ?

Christian

I have several lifelong friends that are New Yorkers but I have always gravitated toward the weirdo's. - Richard Stringer

Re: CString undeclared?!

Yulianto.12-Oct-04 19:52

Yulianto.

12-Oct-04 19:52

Anonymous wrote:
simple user form in visual c++,

What version of VC++ did you use. I think You can`t do that in VC++ 6. Corect me if i`m wrong.

<italic>Work hard and a bit of luck is the key to success.

You don`t need to be genius, to be rich.

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