C / C++ / MFC Discussion Boards

Re: C++ question - Is it a legal action to allocate 0 bytes?

12-Jul-01 8:10

ARM??

Re: C++ question - Is it a legal action to allocate 0 bytes?

markkuk13-Jul-01 8:21

markkuk

13-Jul-01 8:21

The Annotated C++ Reference Manual, it was considered the official definition of the C++ language before the ANSI/ISO standard was approved.

Re: C++ question - Is it a legal action to allocate 0 bytes?

Erik Funkenbusch12-Jul-01 10:21

Erik Funkenbusch

12-Jul-01 10:21

Yes, the standard says that you can allocate a 0 byte array, and that this will be at least 1 unit of storage (on PC's this is one byte) So that it's address may be taken. It's not recommended that you actually DO anything with it though.

Naming child windows

12-Jul-01 5:10

Hello,
Please read the following code.This is for an MDI project in VC++5.
I use this particular method to make MDI documents and windows.
How can I name the frames that I create using this method?

//This is the iitialization.
pDiagramTemplate = new CMultiDocTemplate(
IDR_DIAGRAMTYPE,
RUNTIME_CLASS(CDiagramDoc),
RUNTIME_CLASS(CDiagramChildFrame),
RUNTIME_CLASS(CDiagramView));

//This is for displaying the new frame.

CDiagramChildFrame *pdiagramframe = new CDiagramChildFrame;
CDiagramDoc *pdiagramdoc = new CDiagramDoc;

CDocTemplate *pTemplate = pDiagramTemplate;
CFrameWnd *pframe = pTemplate->CreateNewFrame(pdiagramdoc,pdiagramframe);
pTemplate->InitialUpdateFrame(pframe,pdiagramdoc);

Everything works but I want to name the frames like 1,2,3 etc.as they are created
using THIS PARTICULAR METHOD.Please help me.I need it very very urgently.

Thanx.
Joey Tribbiani.

Re: Naming child windows

Tomasz Sowinski12-Jul-01 7:36

Tomasz Sowinski

12-Jul-01 7:36

What's the relationship between new frame and existing docs? Is this a new window showing new document, or new window for document already associated with other frame windows?

Tomasz Sowinski -- http://www.shooltz.com

Cobol Client using DLL with Dialog

Jim99912-Jul-01 4:28

Jim999

12-Jul-01 4:28

A 3rd party's client app is written in MicroFocus Cobol. My 32 bit DLL exports "int __stdcall DisplayNoGridDlg(HWND hWnd)" which displays a modal dialog. At least it does when called by my C++ test client. When the 3rd party runs their Cobol app it doesn't work.
Debug displays at both sides of the interface show that the value of the handle parameter being sent by the Cobol client is not the same as the value being received so my DLL, which does an IsWindow check, simpy sends back an error.
Is there a trick to getting Cobol and C++ to understand where the interface is in memory?
Confused | :confused:

Re: Cobol Client using DLL with Dialog

Tomasz Sowinski12-Jul-01 7:23

Tomasz Sowinski

12-Jul-01 7:23

This looks like calling convention conflict. The calling convention has impact on the stack layout - and your HWND doesn't get through. I know nothing about MicroFocus Cobol, so can't advice in detail. Check the MF Cobol docs for interfacing to foreign DLLs.

Tomasz Sowinski -- http://www.shooltz.com

Re: Cobol Client using DLL with Dialog

Jim99916-Jul-01 23:36

Jim999

16-Jul-01 23:36

Ta.

Turns out this is a human interface problem. The 3rd party was passing my DLL a pointer to a HWND not a HWND. Apparently pointer params are the default for MF Cobol.

Jim

How can I count the number of open document in MDI

mr200312-Jul-01 4:28

mr2003

12-Jul-01 4:28

Hi,
I like to know if this is the right way to count the number of open documents in MDI :

int i=1;
CWinApp* pApp = AfxGetApp();
POSITION posTemplate = pApp->GetFirstDocTemplatePosition();

while (posTemplate)
{
posTemplate = pApp->GetFirstDocTemplatePosition();
i++;
}

thanks

Ehsan Behboudi

Re: How can I count the number of open document in MDI

Tomasz Sowinski12-Jul-01 7:30

Tomasz Sowinski

12-Jul-01 7:30

This will count the document templates, not the document themselves, and only if you replace GetFirstDocTemplatePosition with GetNextDocTemplate inside the while(...) loop.

With a doctemplate, you can count the documents using CDocTemplate::GetFirstDocPosition/GetNextDoc. You'll have two nested loops - outer loop for iterating over templates and inner loop for documents.

Tomasz Sowinski -- http://www.shooltz.com

Re: How can I count the number of open document in MDI

mr200312-Jul-01 8:17

mr2003

12-Jul-01 8:17

thanks for your help,
I have a small question. How can I cast the pDoc pointer so I could have access to the data of the corresponding document.

int i=0;
int nDocCount = 0;
CWinApp* pApp = AfxGetApp();
POSITION posTemplate = pApp->GetFirstDocTemplatePosition();
while (posTemplate)
{
CDocTemplate *pDocTemplate=pApp->GetNextDocTemplate(posTemplate);
if(NULL!=pDocTemplate)
{
POSITION posDoc = pDocTemplate->GetFirstDocPosition();
while(posDoc)
{
CDocument *pDoc = pDocTemplate->GetNextDoc(posDoc);
////////////////////////////////////////////////////
//I need another pointer to the data of the corresponding doc, or i have to cast pDoc. How can I do that.
///////////////////////////////

if(NULL!=pDoc)
nDocCount++;
}
}
i++;
}
TRACE("%d",nDocCount);

Thanks

Ehsan Behboudi

Re: How can I count the number of open document in MDI

Tomasz Sowinski12-Jul-01 8:30

Tomasz Sowinski

12-Jul-01 8:30

How can I cast the pDoc pointer so I could have access to the data of the corresponding document

Try this...

CDocument *pDoc = pDocTemplate->GetNextDoc(posDoc);
CMyDocument *pMyDoc = (CMyDoc *)pDoc;

... or this:

CDocument *pDoc = pDocTemplate->GetNextDoc(posDoc);
CMyDocument *pMyDoc = static_cast<CMyDocument *>(pDoc);

Tomasz Sowinski -- http://www.shooltz.com

CSplitterWnd

ov12-Jul-01 4:15

12-Jul-01 4:15

I've created a splitted window. And I want my left part of the window to be not less than 150 pixels by X axis. How can I do this?

With the best regards, Vitaly.

Re: CSplitterWnd

Tomasz Sowinski12-Jul-01 4:21

Tomasz Sowinski

12-Jul-01 4:21

Use CSplitterWnd::SetColumnInfo/SetRowInfo. They have a parameter that controls the minimum pane size.

Tomasz Sowinski -- http://www.shooltz.com

Re: CSplitterWnd

ov12-Jul-01 4:24

12-Jul-01 4:24

No, it isn't work the way I need. If I reduce the column width less than cxMin value - it's width will be set to 0. But I need it to be set to the cxMin. At this moment I'm trying to make a child class for CSplitterWnd and correct the width in RecalcLayout().

With the best regards, Vitaly.

Re: CSplitterWnd

ov12-Jul-01 4:35

12-Jul-01 4:35

yeah! it works Smile | :)

With the best regards, Vitaly.

Re: CSplitterWnd

Tomasz Sowinski12-Jul-01 4:38

Tomasz Sowinski

12-Jul-01 4:38

I see - user can drag the splitter to hide a column. RecalcLayout looks very ugly - maybe it's better to hack into OnMouseMove?

Tomasz Sowinski -- http://www.shooltz.com

Re: CSplitterWnd

ov12-Jul-01 4:40

12-Jul-01 4:40

Do you find this ugly?

void CVertSplitter::RecalcLayout() {
	CSplitterWnd::RecalcLayout();
	int cur, min;
	GetColumnInfo(0, cur, min);
	if (cur < min) {
		SetColumnInfo(0, min, min);
		CSplitterWnd::RecalcLayout();
	}
}

With the best regards, Vitaly.

Re: CSplitterWnd

Tomasz Sowinski12-Jul-01 7:13

Tomasz Sowinski

12-Jul-01 7:13

Mea culpa. I didn't realize that RecalcLayout is virtual and you'll have to take the source of CSplitterWnd and make substantial changes.

Cheers,

Tomasz Sowinski -- http://www.shooltz.com

RUN APPLICATION from SCREEN SAVER

12-Jul-01 3:55

I need to run an application from screen saver. When screen saver exists I use this code to launch application.

STARTUPINFO si;
PROCESS_INFORMATION ProcessInformation;
si.cb = sizeof(STARTUPINFO);
si.lpReserved = NULL;
si.lpTitle = NULL;
si.lpDesktop = _T("WinSta0\\Default");
si.dwX = si.dwY = si.dwXSize = si.dwYSize = 0L;
si.dwFlags = 0;;
si.wShowWindow = SW_SHOW;
si.lpReserved2 = NULL;
si.cbReserved2 = 0;
if (::CreateProcess(lpApplicationName, lpszCmdLine, NULL, NULL, FALSE,
0, NULL, NULL, &si, &ProcessInformation))
{
::CloseHandle(ProcessInformation.hProcess);
::CloseHandle(ProcessInformation.hThread);
}

But problem is, this code launch application successfully on Win NT, but I can'tsee launched application on desktop of Win 2k. Another important thing is that when I shutdown my Win 2k system then while shuting down I can see that launched application. I don't know on which desktop this Win 2k launch application.

Please help me in his problem, as I m not getting any idea, as the code is working fine on NT, but is creating problem on Win 2k.

Please help me.

Waiting for reply!
Thanx.

I m really Confused | :confused:

about this Win2k behaviour.

Re: RUN APPLICATION from SCREEN SAVER

Paolo Messina12-Jul-01 10:48

Paolo Messina

12-Jul-01 10:48

Just curious: did you try with
si.lpDesktop = NULL; ?

Paolo.

Frame windows

Troels_Gram12-Jul-01 2:21

Troels_Gram

12-Jul-01 2:21

I'm trying to create a thin frame window, which can still be resized. Problem is that whenever removing the WS_THICKFRAME style from the window I loose the ability to resize the window. How can maintain the resizing capability?

Re: Frame windows

Tomasz Sowinski12-Jul-01 2:34

Tomasz Sowinski

12-Jul-01 2:34

Handle WM_NCHITTEST.

Tomasz Sowinski -- http://www.shooltz.com

CFileFind (Maybe I'll get an answer this time)

Michael Martin12-Jul-01 2:14

Michael Martin

12-Jul-01 2:14

I asked this question yesterday but got no response so will try again. I have used this function successfully in the past, so don't know why I can't get it to work now.

I have the follow file on disk D:\Import\ReadMe.txt, when I search for it, it doesn't get found.

According to help I need to call FindNextFile() after I call FindFile() before I can access any of the other member functions

::SetCurrentDirectory("D:\\Import");
 
CFileFind	Find;
 
// Start search
Find.FindFile("ReadMe.txt");
 
// Cycle through files
while (Find.FindNextFile())
{
    if (!Find.IsDots() &&
        !Find.IsDirectory())
    {
        CString strMsg = Find.GetFilePath();
        strMsg += " found.";
        AfxMessageBox(strMsg, MB_OK | MB_APPLMODAL | MB_ICONSTOP);
    }
}
 
Find.Close();

Any ideas what I have stuffed up and more importantly any answers to my problem?

Michael Martin
Pegasystems Pty Ltd
Australia
martm@pegasystems.com
+61 413-004-018

Re: CFileFind (Maybe I'll get an answer this time)

Tomasz Sowinski12-Jul-01 2:30

Tomasz Sowinski

12-Jul-01 2:30

You should use BOOL value returned from FindFile:

BOOL bWorking = finder.FindFile("D:\\dir\\ReadMe.txt");
	while (bWorking)
	{
		bWorking = finder.FindNextFile();
		if (!finder.IsDots() &&	!finder.IsDirectory())    
		{        
			CString strMsg = finder.GetFilePath();        
			strMsg += " found.";        
			AfxMessageBox(strMsg, MB_OK | MB_APPLMODAL | MB_ICONSTOP);    
		}
	} 
	finder.Close();

Tomasz Sowinski -- http://www.shooltz.com

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