Please Help! What would cause Member Variable problem? - C / C++ / MFC Discussion Boards

El Corazon12-Apr-06 13:28

12-Apr-06 13:28

ilda lapi wrote:
I am a beginner in Visual Studio C++.
In all I have read till know I can't find an example of how to plot,

In addition to the post on DC, you can also change that context into either an OpenGL or Direct3D display, thus allowing you a full range of very low-level drawing functions.

and there are additional methods such as GDI+ depending on your needs. http://www.codeproject.com/miscctrl/pgllib.asp[^]

there are actually quite a few ways to do plotting through various frameworks to libraries.

_________________________
Asu no koto o ieba, tenjo de nezumi ga warau.
Talk about things of tomorrow and the mice in the ceiling laugh. (Japanese Proverb)

Device drivers: MSVAD sample drivers

imsaady12-Apr-06 10:04

imsaady

12-Apr-06 10:04

I have to develop a device driver for windows NT that will add a virtual audio device to the system. i need to hook up and capture the audio stream coming from microphone and send it to two differnt application. one sugesstion i got from Kakan is to develop a filter driver.

Now can a filter driver be used to install a virtual device.

there are MSVAD sample drivers in DDK. are thay filter drivers?
can i use those sample codes for my work.

saad

Editing long lines in VC++ 6.0

Ger Hayden12-Apr-06 9:22

Ger Hayden

12-Apr-06 9:22

Hi,
I have a line that I want to key as follows:

m_Query.Format("select Route_ID
Stage_ID,
Price,
valid_from,
valid_to,
Price_Key
from TicketPrice
where Ticket_Type = '%s'
FOR UPDATE", m_selected_id);

However I get C2001 newline in constant messages from the compiler. Anyone know the line continuation symbol?

Ger

Re: Editing long lines in VC++ 6.0

David Crow12-Apr-06 9:39

David Crow

12-Apr-06 9:39

Ger Hayden wrote:
Anyone know the line continuation symbol?

You can either use the backslash character like:

m_Query.Format("select Route_ID \
    Stage_ID, \
    Price, \
    valid_from, \
    valid_to, \
    Price_Key \
    from TicketPrice \
    where Ticket_Type = '%s' \
    FOR UPDATE", m_selected_id);

or enclose each string in quotes like:

m_Query.Format("select Route_ID "
               "Stage_ID, "
               "Price, "
               "valid_from, "
               "valid_to, "
               "Price_Key "
               "from TicketPrice "
               "where Ticket_Type = '%s' "
               "FOR UPDATE", m_selected_id);

"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: Editing long lines in VC++ 6.0

Ger Hayden12-Apr-06 9:50

Ger Hayden

12-Apr-06 9:50

Thanks David,
Both forms work perfectly

GER

Ger

VC++ 6 project works in debug but not release

smikesmith12-Apr-06 8:56

smikesmith

12-Apr-06 8:56

I've built a fairly simple MFC project, dialog based, that talks to a USB GPS device. The program uses a second thread to receive data at a 1-second rate and display the information in text form. When a data packet is received, the worker thread sends a message to the DlgWindow to tell it to get the new information. The call is:

if (pThis->m_hWndPost)<br />
::PostMessage (pThis->m_hWndPost, pThis->m_nMessageID, 0, 0);<br />

This works correctly in the Debug version of the project. However, when the Release version is built, the second call to ::PostMessage() crashes. I've isolated that code, and if I don't call the message post, no problem (of course, the DlgWnd never gets the new data). If I trap the message at the responding function in the DlgWnd, it crashes.

One work-around: if I set the compiler options to build using the debug libraries, either stand-alone or with shared MFC DLL, the problem goes away. I can't find that I have any corrupted libraries (and no reason to suspect).

Has anyone ever seen this problem before? Any ideas what I'm doing wrong? Turning off optimizations has no effect, either.

Thanks,
Mike

Re: VC++ 6 project works in debug but not release

prasad_som12-Apr-06 19:21

prasad_som

12-Apr-06 19:21

In debug mode, compiler takes care of things like initialization.
Check if all variables used are properly initialized.
Use NULL check before using pointers.

This is just a try. I'm not sure , why crash is happening.

Please Help! What would cause Member Variable problem?

Charlie Curtis12-Apr-06 8:54

Charlie Curtis

12-Apr-06 8:54

Hi EveryOne!,

I will add code later, but I am having a problem with member variables. As you will see in the code the variables are being created and ClassWizard recognizes them. However, when I try to access them in the .CPP file they aren't working (I can add events from class wizard for them). I.E. I copy the variable from it's definition in the header file place it where I need it in the .CPP file and place a . (dot) after it, but it does not provide me a list of member functions that should be available. It does nothing. There is one exception and that is the m_CalUICCombo it works fine. The m_FySelected (also a ComboBox) does not work? Following is the Header file followed by the .cpp file. To keep this post down I've only inserted the relavant parts. Has anyone every run into this problem and if so what did you do to fix it?

Many Thanks in advance...
Charlie

// Header File Starts Here.<br />
class CECalAppendixIForm : public CFormView<br />
{<br />
protected:<br />
	CECalAppendixIForm();           // protected constructor used by dynamic creation<br />
	DECLARE_DYNCREATE(CECalAppendixIForm)<br />
<br />
// Form Data<br />
public:<br />
	//{{AFX_DATA(CECalAppendixIForm)<br />
	enum { IDD = IDD_APPENDIXI_FORM_VIEW };<br />
	CComboBox			m_FySelected;<br />
	CLabel				m_SelectedItemsLabel;<br />
	CLabel				m_AppendixILabel;<br />
	CComboBox			m_CalUICCombo;<br />
	//}}AFX_DATA<br />
<br />
// Attributes  <br />
public:<br />
	SYSTEMTIME ct;<br />
<br />
<br />
	CImgViewerDoc* GetDocument();<br />
	CString csHdrLine;<br />
// Operations<br />
public:<br />
<br />
// Overrides<br />
	// ClassWizard generated virtual function overrides<br />
	//{{AFX_VIRTUAL(CECalAppendixIForm)<br />
	public:<br />
	virtual void OnInitialUpdate();<br />
	protected:<br />
	virtual void DoDataExchange(CDataExchange* pDX);    // DDX/DDV support<br />
	virtual void OnDraw(CDC* pDC);<br />
	//}}AFX_VIRTUAL<br />
<br />
// Implementation<br />
protected:<br />
	virtual ~CECalAppendixIForm();<br />
#ifdef _DEBUG<br />
	virtual void AssertValid() const;<br />
	virtual void Dump(CDumpContext& dc) const;<br />
#endif<br />
<br />
	// Generated message map functions<br />
	//{{AFX_MSG(CECalAppendixIForm)<br />
	afx_msg void OnCloseupCalUIC();<br />
	afx_msg void OnCloseupFySelected();<br />
	//}}AFX_MSG<br />
	DECLARE_MESSAGE_MAP()<br />
};<br />
<br />
// Source file Starts Here.<br />
<br />
IMPLEMENT_DYNCREATE(CECalAppendixIForm, CFormView)<br />
<br />
CECalAppendixIForm::CECalAppendixIForm()<br />
	: CFormView(CECalAppendixIForm::IDD)<br />
{<br />
	//{{AFX_DATA_INIT(CECalAppendixIForm)<br />
	//}}AFX_DATA_INIT<br />
}<br />
<br />
CECalAppendixIForm::~CECalAppendixIForm()<br />
{<br />
}<br />
<br />
void CECalAppendixIForm::DoDataExchange(CDataExchange* pDX)<br />
{<br />
	CFormView::DoDataExchange(pDX);<br />
	//{{AFX_DATA_MAP(CECalAppendixIForm)<br />
	DDX_Control(pDX, IDC_FYSELECTED, m_FySelected);<br />
	DDX_Control(pDX, IDC_SELECTITEMS, m_SelectedItemsLabel);<br />
	DDX_Control(pDX, IDC_APPENDIXI, m_AppendixILabel);<br />
	DDX_Control(pDX, IDC_CALUICOMBO, m_CalUICCombo);<br />
	//}}AFX_DATA_MAP<br />
}<br />
<br />
<br />
BEGIN_MESSAGE_MAP(CECalAppendixIForm, CFormView)<br />
	//{{AFX_MSG_MAP(CECalAppendixIForm)<br />
	ON_CBN_CLOSEUP(IDC_CALUICOMBO, OnCloseupCalUIC)<br />
	ON_CBN_CLOSEUP(IDC_FYSELECTED, OnCloseupFySelected)<br />
	//}}AFX_MSG_MAP<br />
END_MESSAGE_MAP()<br />
<br />
#ifdef _DEBUG<br />
void CECalAppendixIForm::AssertValid() const<br />
{<br />
	CFormView::AssertValid();<br />
}<br />
<br />
void CECalAppendixIForm::Dump(CDumpContext& dc) const<br />
{<br />
	CFormView::Dump(dc);<br />
}<br />
#endif //_DEBUG<br />
<br />
CImgViewerDoc* CECalAppendixIForm::GetDocument() // non-debug version is inline<br />
{<br />
	//ASSERT(m_pDocument->IsKindOf(RUNTIME_CLASS(CECalTrackingDoc)));<br />
	m_pDocument->IsKindOf(RUNTIME_CLASS(CImgViewerDoc));<br />
	return (CImgViewerDoc*)m_pDocument;<br />
}<br />
/////////////////////////////////////////////////////////////////////////////<br />
// CECalAppendixIForm message handlers<br />
<br />
void CECalAppendixIForm::OnDraw(CDC* pDC) <br />
{<br />
	SetScrollSizes(MM_TEXT, CSize(1200,1200)); // Larger than the Frame so the VScroll Bar is shown.<br />
	CImgViewerDoc* pDoc = GetDocument();<br />
	pDoc->csHdrLine = "APPENDIX I";<br />
	pDoc->UpdateAllViews(this);<br />
}<br />
<br />
void CECalAppendixIForm::OnCloseupCalUIC() <br />
{<br />
}<br />
<br />
void CECalAppendixIForm::OnInitialUpdate() <br />
{<br />
	CFormView::OnInitialUpdate();<br />
	<br />
	CSize sizeTotal;<br />
<br />
	// These sizes insure that when the OnDraw Function is called with larger values<br />
	// The VScrollBar will be drawn.<br />
	sizeTotal.cx = 250;<br />
	sizeTotal.cy = 100;<br />
	SetScrollSizes(MM_TEXT, sizeTotal);<br />
<br />
	m_SelectedItemsLabel.SetWindowText("There are No Input Item(s) required for this Appendix.");<br />
	m_AppendixILabel.SetTextColor(RGB(0,100,130));<br />
	m_AppendixILabel.SetFontName("Times New Roman");<br />
	m_AppendixILabel.SetFontSize(14);<br />
	m_AppendixILabel.SetFontBold(FALSE);<br />
	m_AppendixILabel.SetFontUnderline(FALSE);<br />
	m_AppendixILabel.ShowWindow(SW_SHOW);<br />
}<br />
<br />
void CECalAppendixIForm::OnCloseupFySelected() <br />
{<br />
	// TODO: Add your control notification handler code here<br />
	<br />
}

Everything is Free... Until You Have to Pay for it...

Platforms Windows 2000/XP Professional using Visual C++ 6.0

Re: Please Help! What would cause Member Variable problem?

David Crow12-Apr-06 9:10

David Crow

12-Apr-06 9:10

Without having to wade through all of the code, are you having trouble with IntelliSense?

"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: Please Help! What would cause Member Variable problem?

Charlie Curtis12-Apr-06 9:26

Charlie Curtis

12-Apr-06 9:26

Let me see if I can make the problem a little more clear. When I go to my OnDraw function in the source file and put in m_CalUICCombo. I get a scrollable list box of the functions/variables I can access for that combobox. When I type m_FySelected. I do not receive the scrollable list box giving me those choices for that combobox. I hope this will make it a little more clear what I am having a problem with. So I am not sure if that would be a problem with intellisense? Any further advice would be appreciated.

Everything is Free... Until You Have to Pay for it...

Platforms Windows 2000/XP Professional using Visual C++ 6.0

Re: Please Help! What would cause Member Variable problem?

David Crow12-Apr-06 9:34

David Crow

12-Apr-06 9:34

Charlie Curtis wrote:
So I am not sure if that would be a problem with intellisense?

It is. See if this helps.

"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: Please Help! What would cause Member Variable problem?

Charlie Curtis12-Apr-06 10:10

Charlie Curtis

12-Apr-06 10:10

Appreciate your time and effort. I followed the link and found the information very useful for future reference. however, for the problem I had today it turns out that my .ncb, .aps, and .clw files got corrupted. I deleted them and reopened my project rebuilt the class wizard and all is well. Thanks again for the info.
Charlie

Everything is Free... Until You Have to Pay for it...

Platforms Windows 2000/XP Professional using Visual C++ 6.0

Re: Please Help! What would cause Member Variable problem?

David Crow12-Apr-06 10:17

David Crow

12-Apr-06 10:17

Charlie Curtis wrote:
...my .ncb, .aps, and .clw files got corrupted. I deleted them and reopened my project rebuilt the class wizard and all is well.

Yes, that is a common problem, too.

"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

Problem when Change number of arguments of MFC activeX control's exposed method

Michael Tang12-Apr-06 8:48

Michael Tang

12-Apr-06 8:48

Please forgive my bad English first.

I changed the number of arguments of one of exposed methods of an old MFC activeX control. Then I just can't call it any more either in VB or ActiveX Control Test Container.

Here are the steps:
1).
I built a MFC activeX control with one of its exposed functions requiring 1 arguments. I registered the control and built a test VB application and it was OK.

2).
Then I changed that function to having 2 arguments and built the control again. And I also registered it again.

3).
The I changed calling code in the test VB application accordingly. But it just failed to call the function by remind me "Invalid number of arguments".

Any help will be greatly appreciated!

Re: Problem when Change number of arguments of MFC activeX control's exposed method

Michael Tang12-Apr-06 9:42

Michael Tang

12-Apr-06 9:42

I think I found an IMPORTANT message. It's a warning when I compile the new MFC control in VC 6.0:

: warning C4002: too many actual parameters for macro 'DISP_FUNCTION'

I think this the very reason of the problem. But I have manually changed the method declarations in all the places.

Why is there this compiling WARNING?

Re: Problem when Change number of arguments of MFC activeX control's exposed method

prasad_som12-Apr-06 19:41

prasad_som

12-Apr-06 19:41

Michael Tang wrote:
: warning C4002: too many actual parameters for macro 'DISP_FUNCTION'

It says you have added one additional parameter in macro defn.
Make your macro defn look like one following

DISP_FUNCTION(mycorntrolclass, "MyMethod", MyMethod, VT_EMPTY/*return type*/, VTS_PI4 VTS_PI4/* nos of params should be space separated, dont use comma inbetn*/)

make sure you activex builds without any warning.
Add its reference to your client program again.

Re: Problem when Change number of arguments of MFC activeX control's exposed method

Michael Tang13-Apr-06 4:05

Michael Tang

13-Apr-06 4:05

prasad_som, A thousand thanks to you!
You just hit it, Now it's solved by killing the redundant comma.
I had checked the macro difinition I changed for so many times, but I just omitted the comma. Smile | :)

Re: Problem when Change number of arguments of MFC activeX control's exposed method

prasad_som17-Apr-06 2:09

prasad_som

17-Apr-06 2:09

my pleasure Smile | :)

call stack not getting created

inamulev12-Apr-06 8:29

inamulev

12-Apr-06 8:29

We have added the stackwalker.cpp program to our application to generate callstack report.
This is working fine in the development environment and the stacktrace is getting created.
But when we copy the executable to a separate windows system where there is no development environment like visual studio installed, the stacktrace is not getting created. Is this error
due to some missing dll files in the isolated system where we dont have visual studio installed
or do we have to make some changes in the way we are compiling and building the application.
Any suggestions would be of immense help.

importing a .net dll into VC6

Waldermort12-Apr-06 8:23

Waldermort

12-Apr-06 8:23

I have searching for hours now trying to figure this one out. I have a .NET dll, not my own, which I wish to import into my project. From what I have read, and I may be wrong, I need to import it as a COM object. So I have tried

#import "net.dll"

which results in:
fatal error C1083: Cannot open type library file: 'net.dll': Error loading type library/DLL.

This leads me to believe that the dll has no type library. When I have included my own VB dlls using the same method, I have no problems, the .tli and .tlb files are generated.

Is there another way to do this?

Re: importing a .net dll into VC6

oshah12-Apr-06 13:16

oshah

12-Apr-06 13:16

You haven't yet created the Type library for the .NET DLL. To create a type library, you need to make use of the regasm.exe tool.

regasm.exe net.dll

Also make sure you have set the [ComVisible(true)] attribute

Re: importing a .net dll into VC6

Michael Dunn12-Apr-06 15:24

Michael Dunn

12-Apr-06 15:24

You can't do .net programming with VC6.
The best you can do is make the DLL have a CCW (COM callable wrapper) and then VC6 will see it as just another COM server.

--Mike--
Visual C++ MVP Cool | :cool:

LINKS~! Ericahist | NEW!! PimpFish | CP SearchBar v3.0 | C++ Forum FAQ

Re: importing a .net dll into VC6

Waldermort12-Apr-06 19:59

Waldermort

12-Apr-06 19:59

Michael Dunn wrote:
You can't do .net programming with VC6.

does that mean I can't code VB in VC either :p

The dll I am trying to use is from a sourceforge project which has been coded in C#. I do not have the means to compile from source therefore I have to download the precompiled version. So I suppose my question is, to make this work in my project, would I have to change anything within the .net dll?

Compile Error with __stdcall

gmhanna12-Apr-06 8:00

gmhanna

12-Apr-06 8:00

Hi,

I'm trying to convert a C application written for Watcom's C/C++ compiler to Visual C/C++ and I'm getting a compile error on the file that contains some of the prototypes, yet I do not understand what went wrong and how it's different.

Here's the line from the prototype file:

LONG EXPENTRY   fnwpMainWindow(<br />
                 HWND hwnd, UINT msg, WPARAM mp1, LPARAM mp2 );

EXPENTRY is defined as an _export APIENTRY, APIENTRY is defined as a WINAPI and WINAPI is defined as __stdcall.

The error I'm receiving is error C2143: syntax error : missing '{' before '__stdcall'

Any idea's why this is happening?

Thank you,

Glenn

Re: Compile Error with __stdcall

David Crow12-Apr-06 8:22

David Crow

12-Apr-06 8:22

gmhanna wrote:
The error I'm receiving is error C2143: syntax error : missing '{' before '__stdcall'

So what is above the fnwpMainWindow() prototype?

What if you changed it to:

long _export __stdcall fnwpMainWindow(HWND hwnd, UINT msg, WPARAM mp1, LPARAM mp2 );

"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

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