C / C++ / MFC

A question about bitmap ?

22-Nov-01 22:16

Use CWnd::SetIcon.
Put it in the OnInitDialog of your child dialog.

If your child window is not a dialog, then put it in OnCreate.

Nish

Sonork ID 100.9786 voidmain

www.busterboy.org

Nish is a BIG fan of Goran Ivanisevic

Leesen22-Nov-01 21:57

Leesen

22-Nov-01 21:57

Hi,
all
I have loaded in a bitmap in my program.And I have draw
some lines on the bitmap .Now I want to store this new bitmap with lines on it. How should I do???
Expect your help.

Re: A question about bitmap ?

Nish Nishant22-Nov-01 22:27

A bug concerning 2 threads in my program

22-Nov-01 22:27

Hi Bliven

I havent done much bitmap stuff.
But this URL might help you, I hope.

http://www.codeproject.com/bitmap/cximage.asp

Regards
Nish

Sonork ID 100.9786 voidmain

www.busterboy.org

Nish is a BIG fan of Goran Ivanisevic

22-Nov-01 21:13

Hi there! Below is my problematic dialog-based program that has 2 threads : the program's primary thread and a second thread.
This program has a pushbutton, and when clicked, a modal dialog box pops up.
The program downloads a specified file from the Internet to the user's hard disk.

Name of main program dialog class : CDownloaderDlg
Name of modal dialog class : CUpdateDlg

Below, is my code for showing the modal dialog box when the pushbutton is clicked in the main dialog :

"#include "UpdateDlg.h"
void CDownloaderDlg::OnUpdatenow()
{
//show the modal dialog box
CUpdateDlg dlg(this);
dlg.DoModal();
}

Now, after running the code above, a modal dialog box(CUpdateDlg) will pop up, right?

//*******Below is all my code for the UpdateDlg.cpp file.*********

//I link this program with the WinInet library, cos' it's required
// UpdateDlg.cpp : implementation file
//

#include "stdafx.h"
#include "Downloader.h"
#include "UpdateDlg.h"

#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

//include afxinet.h header file
#include <afxinet.h>

const UINT WM_HTTPDOWNLOAD_THREAD_FINISHED = WM_APP + 1;

/////////////////////////////////////////////////////////////////////////////
// CUpdateDlg dialog

CUpdateDlg::CUpdateDlg(CWnd* pParent /*=NULL*/)
: CDialog(CUpdateDlg::IDD, pParent)
{
//{{AFX_DATA_INIT(CUpdateDlg)
// NOTE: the ClassWizard will add member initialization here
//}}AFX_DATA_INIT

//m_pThread is a CWinThread member variable
m_pThread = NULL;
//m_bSafeToClose is a BOOL member variable
m_bSafeToClose = FALSE;
}

void CUpdateDlg::DoDataExchange(CDataExchange* pDX)
{
CDialog::DoDataExchange(pDX);
//{{AFX_DATA_MAP(CUpdateDlg)
DDX_Control(pDX, IDC_STATUS_PERCENTAGE, m_Status_Percentage);
DDX_Control(pDX, IDC_STATUS_KB, m_Status_KB);
DDX_Control(pDX, IDC_DOWNLOADSTATUS, m_DownloadStatus);
//}}AFX_DATA_MAP
}

BEGIN_MESSAGE_MAP(CUpdateDlg, CDialog)
//{{AFX_MSG_MAP(CUpdateDlg)
ON_BN_CLICKED(IDC_DOWNLOAD, OnDownload)
ON_WM_DESTROY()
ON_WM_CLOSE()
//}}AFX_MSG_MAP
ON_MESSAGE(WM_HTTPDOWNLOAD_THREAD_FINISHED, OnThreadFinished)
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CUpdateDlg message handlers

LRESULT CUpdateDlg::OnThreadFinished(WPARAM wParam, LPARAM /*lParam*/)
{
m_bSafeToClose = TRUE;

EndDialog(IDCANCEL);

return 0L;
}

//function for downloading a file from the Internet
//you don't realy need to know this function, though.
CString CUpdateDlg::DownloadFile(const char *url, const char *filename)
{
// Size of HTTP Buffer...
#define HTTPBUFLEN 512
char httpbuff[HTTPBUFLEN];
TCHAR szCause[255];
int nFileSize = 0;
CString Cause;
Cause.Format("YES");

TRY
{
CInternetSession mysession;
CStdioFile *remotefile = mysession.OpenURL(url,1,INTERNET_FLAG_TRANSFER_BINARY|INTERNET_FLAG_RELOAD);

DWORD dwFileSize;
char szSizeBuffer[32];
DWORD dwLengthSizeBuffer = 32;
HINTERNET hFileInfo;

hFileInfo = InternetOpenUrl(mysession, url, NULL, 0, 0, 0);

BOOL bQuery = ::HttpQueryInfo(hFileInfo,HTTP_QUERY_CONTENT_LENGTH, szSizeBuffer, &dwLengthSizeBuffer, NULL) ;

if(bQuery)
{
dwFileSize = atol(szSizeBuffer);
::InternetCloseHandle(hFileInfo);

//store the file size in an int variables,
//and divide it by 1024 to convert it to KB.
nFileSize = dwFileSize / 1024;

//set the range of progress bar to the total file size
m_DownloadStatus.SetRange32(0,nFileSize);
}
else
{
MessageBox("Unable to retrieve file sizes!","Error",MB_OK | MB_ICONWARNING);
}

CFile myfile(filename, CFile::modeCreate|CFile::modeWrite|CFile::typeBinary);
int numbytes = 0, nBytesTransfered = 0;

while(numbytes = remotefile->Read(httpbuff, HTTPBUFLEN))
{
//set the position accordingly in the progress bar
m_DownloadStatus.SetPos(nBytesTransfered / 1024);
}
}

CATCH_ALL(error)
{
error->GetErrorMessage(szCause,254,NULL);
Cause.Format("%s",szCause);
}
END_CATCH_ALL;

return (Cause);
}

UINT CUpdateDlg::_DownloadThread(LPVOID pParam)
{
//Convert from the SDK world to the C++ world
CUpdateDlg* pDlg = (CUpdateDlg*) pParam;
ASSERT(pDlg);
ASSERT(pDlg->IsKindOf(RUNTIME_CLASS(CUpdateDlg)));
pDlg->DownloadFile("http://www.geocities.com/xeon_boy/Dinos.zip","C:\\Windows\\Desktop\\ght.zip");
return 0;
}

void CUpdateDlg::OnDownload()
{
// TODO: Add your control notification handler code here

m_pThread = AfxBeginThread(_DownloadThread, this, THREAD_PRIORITY_NORMAL, CREATE_SUSPENDED);
m_pThread->m_bAutoDelete = FALSE;
m_pThread->ResumeThread();
}

void CUpdateDlg::OnCancel()
{
PostMessage(WM_HTTPDOWNLOAD_THREAD_FINISHED);

CDialog::OnCancel();
}

void CUpdateDlg::OnDestroy()
{
CDialog::OnDestroy();

// TODO: Add your message handler code here

if (m_pThread)
{
WaitForSingleObject(m_pThread->m_hThread, INFINITE);
delete m_pThread;
m_pThread = NULL;
}
}

void CUpdateDlg::OnClose()
{
// TODO: Add your message handler code here and/or call default

if(m_bSafeToClose)
{
CDialog::OnClose();
}
}

The thing is that when I run the program and the downloading process is half-way through
and I click the Cancel button(IDCANCEL , OnCancel), the modal dialog(CUpdateDlg) closes down
and everything is fine, but the main program HANGS and everything gets stucks! And I've to use
Alt + Ctrl + Del to close down the thing! Can you please help me? I've been trying this fro around 2 weeks and 3 days,
but just couldn't find the bug even after days and days of re-coding and testing and building and testing again.

Also, if you wish, I can send you the program for you to inspect, just give me your e-mail address.

Please help!!! Thanks a lot, really......in advance!

Good day,
Xeon

Re: A bug concerning 2 threads in my program

Joaquín M López Muñoz22-Nov-01 22:21

Joaquín M López Muñoz

22-Nov-01 22:21

There are several little flaws in your code. The main problem is that the downloading thread does not provide any method for premature cancellation, so when you press cancel the program starts closing before it is safe to close the dialog.
I propose you follow this schema: Add a BOOL variable to indicate the thread to exit (m_bTimeToDie for instance), and have the downloading loop check for it. Then, change things according to this:

LRESULT CUpdateDlg::OnThreadFinished(WPARAM wParam, LPARAM /*lParam*/)
{
  m_bSafeToClose = TRUE;
  EndDialog(IDCANCEL);
  return 0L;
}

CString CUpdateDlg::DownloadFile(const char *url, const char *filename)
{
  ... // remember to check for m_bTimeToDie

  PostMessage(WM_HTTPDOWNLOAD_THREAD_FINISHED);
  return (Cause);
}

void CUpdateDlg::OnCancel() 
{
    if(m_pThread){
      m_bTimeToDie=TRUE; // thread termination will 
      GetDlgItem(IDCANCEL)->EnableWindow(FALSE); // no more cancels, we already know
    }
    else EndDialog(IDCANCEL);
}

void CUpdateDlg::OnDestroy() 
{
  if(m_pThread){
    ::WaitForSingleObject(m_pThread->m_hThread,INFINITE);
    delete m_pThread;
    m_pThread=NULL;
  }

  CDialog::OnDestroy();
}

void CUpdateDlg::OnClose() 
{
  if(m_bSafeToClose)CDialog::OnClose();
  else{ //like OnCancel()
    if(m_pThread){
      m_bTimeToDie=TRUE;	
      GetDlgItem(IDCANCEL)->EnableWindow(FALSE);
    }
    else EndDialog(IDCANCEL);
  }
}

Hope this helps.

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

Handle of one window.

22-Nov-01 21:01

I need the window handle, having the ID Process, the ID Thread, the handle Process,and the handle Thread of the process that launch the application.

Re: Handle of one window.

Nish Nishant22-Nov-01 21:26

Re: Handle of one window.

22-Nov-01 21:26

Take a look at EnumThreadWindows

Nish

Sonork ID 100.9786 voidmain

www.busterboy.org

Nish is a BIG fan of Goran Ivanisevic

25-Nov-01 21:15

when the process is unique, but it has more windows (for example WINWORD.EXE), I find the HANDLE at the first window, but not the HANDLES of other windows

Custom control for displaying status

Christopher Lord22-Nov-01 18:32

Christopher Lord

22-Nov-01 18:32

I am wondering if anyone could give me some pointers on making a reuseable control that has the following features.

It needs to be able to display small 16x16 icons in the position i want. no text, perhaps a tooltip.

Next, it has to change the icons when i want to... this is fairly easy.

And finally, it has to have a focus rect around the currently selected bitmap, and this selection must be retrivable by a call into it, also easy.

what i need advice on, is would I subclass out of a generic static control to do this, or would it be better to slap some bitmaps into a gdi surface?
Is there a good totorial on creating controls such as this, or, how would i go about making this out of pure gdi?

thanks for your tips!

Re: Custom control for displaying status

Michael Dunn22-Nov-01 19:47

22-Nov-01 19:47

You can do almost all of that with the list view control. The standard control shows the focus rect around the label, not the icon, but you can draw your own focus indicator if you custom draw the icons.

--Mike--
http://home.inreach.com/mdunn/
While I can't be correct on all matters, I can make the reassuring claim that where I am inaccurate, I am at least definitively inaccurate.
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Re: Is CSocket "secure"?

Nish Nishant22-Nov-01 19:08

22-Nov-01 19:08

If you mean buffer overflows it's not about CSocket. It's a problem with all TCP/IP server-programs.

Nish

Sonork ID 100.9786 voidmain

www.busterboy.org

Nish is a BIG fan of Goran Ivanisevic

Re: Is CSocket "secure"?

Rashid Thadha22-Nov-01 22:34

Rashid Thadha

22-Nov-01 22:34

If you want your data to be secure then you need to use SSL (Secure Socket Layer) with your socket class.

Text Processing

Nick Parker22-Nov-01 18:07

22-Nov-01 18:07

I am writing a program in C++ that opens a file, reads through it character by character counting each individual character, that I am later to create a histogram for. That part I have done, however, I am having a problem with the last part. It need to Rewrite the sentences inside the file so the first letter of each sentence is capitalized and everything else is lowercase. I am also having a problem validating a space between words, any help would be great. Thanks in advance.

P.S. -- I am doing something like this to check for a space.

// x is the letter I am reading in
char x;

if(isspace(x) != 0)
{
cout << "I hit a space";
outfile << " ";
}

Nick Parker

Michael Dunn22-Nov-01 19:50

22-Nov-01 19:50

What do you mean by "validating" a space?

--Mike--
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While I can't be correct on all matters, I can make the reassuring claim that where I am inaccurate, I am at least definitively inaccurate.
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Nick Parker23-Nov-01 4:09

23-Nov-01 4:09

The space between these words would all count as a space, as would a line feed, tab, and form feed. Which is why I felt that using the isspace() function should be proper. I am iccorectly using this, because it doesn't seem to be working for me. Should I not use a char variable to read this in ??
I am just not really sure where to go with this. Thanks.

Nick Parker

Michael Dunn23-Nov-01 8:14

23-Nov-01 8:14

Ok, so you're just keeping a "whitespace" counter, and incrementing it every time you find a space/tab/etc in the input. isspace() should do that. I'd suggest tracing thru isspace() to see if it's not returning true like you expect when you hit a tab/form feed/etc.

--Mike--
http://home.inreach.com/mdunn/
While I can't be correct on all matters, I can make the reassuring claim that where I am inaccurate, I am at least definitively inaccurate.
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Nick Parker23-Nov-01 10:57

23-Nov-01 10:57

Does this sound like it should work, and print a blank space then as well?

do{

infile >> x;

if(isspace(char(x)) != 0)
{
cout << "Space hit!!!\n";
outfile << " ";
}
else
{
cout << x << '\n';
outfile << x;
}

}while(!infile.eof());

Thanks for your help Smile | :)

Nick Parker

Michael Dunn23-Nov-01 11:17

23-Nov-01 11:17

One catch about istream::eof is that it returns true only after you've read the EOF marker. So right after infile >> x;, add if ( !infile.eof() ). Otherwise, you'll parse the last character in the file twice.

--Mike--
http://home.inreach.com/mdunn/
While I can't be correct on all matters, I can make the reassuring claim that where I am inaccurate, I am at least definitively inaccurate.
Heart | [heart]

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Nick Parker24-Nov-01 1:54