C / C++ / MFC

ThatsAlok1-Sep-06 1:56

ThatsAlok

1-Sep-06 1:56

raserove wrote:
have an MFC Server/Client multithreaded Application, now i'm looking to rewrite in C#.Net. It uses Oracle 9i as database. Before i jump to my development work, i need to clarify if it is a right move to write in .net when it comes to performance (server), ease of development, etc.

.Net is new technology, better you switch over to it or become extinct Smile | :)

"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow

cheers,
Alok Gupta
VC Forum Q&A :- I/ IV
Support CRY- Child Relief and You

Zac Howland1-Sep-06 4:07

Zac Howland

1-Sep-06 4:07

ThatsAlok wrote:
.Net is new technology, better you switch over to it or become extinct

.Net may be new, but native applications will never be extinct. There are many types of applications that managed code does not perform well enough to replace non-managed code.

If you decide to become a software engineer, you are signing up to have a 1/2" piece of silicon tell you exactly how stupid you really are for 8 hours a day, 5 days a week

Zac

ThatsAlok1-Sep-06 5:14

ThatsAlok

1-Sep-06 5:14

Zac Howland wrote:
.Net may be new, but native applications will never be extinct. There are many types of applications that managed code does not perform well enough to replace non-managed code.

i don't want to go in discussion of same! better leave this topic here only!

"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow

cheers,
Alok Gupta
VC Forum Q&A :- I/ IV
Support CRY- Child Relief and You

Zac Howland1-Sep-06 5:24

Zac Howland

1-Sep-06 5:24

ThatsAlok wrote:
i don't want to go in discussion of same! better leave this topic here only!

You were the one that brought it up Poke tongue | ;-P

If you decide to become a software engineer, you are signing up to have a 1/2" piece of silicon tell you exactly how stupid you really are for 8 hours a day, 5 days a week

Zac

Shell Namespace Extension Question

ThatsAlok1-Sep-06 5:56

ThatsAlok

1-Sep-06 5:56

Zac Howland wrote:

You were the one that brought it up

thats why he he he Smile | :)

"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow

cheers,
Alok Gupta
VC Forum Q&A :- I/ IV
Support CRY- Child Relief and You

RSL-REK31-Aug-06 14:34

RSL-REK

31-Aug-06 14:34

Hello,
I am trying to implement drag within my shell namespace extension. I noticed that in MFC you are able to set up a message area to attach to the events such as OnBeginDrag.

My question is; How do I attach to those events using c#?

Thank you,
Rick

Rick

Re: Shell Namespace Extension Question

ThatsAlok1-Sep-06 1:57

ThatsAlok

1-Sep-06 1:57

RSL-REK wrote:
How do I attach to those events using c#?

ask here http://www.codeproject.com/script/comments/forums.asp?forumid=1649[^]

"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow

cheers,
Alok Gupta
VC Forum Q&A :- I/ IV
Support CRY- Child Relief and You

How to create GDI+ Metafile from CMetaFileDC?

shinano31-Aug-06 14:15

shinano

31-Aug-06 14:15

I am working on a drawing application using MFC and GDI+.
Now I am checking the following method
virtual BOOL OnDraw(CDC* pDC, CSize& rSize);
in my class derived from COleServerItem.
(This method is called to draw OLE item to metafile by framework.)

In this method, (actually pDC is pointer to CMetaFileDC object.)
following code
Metafile mf(pDC->m_hDC);
is failed, as lastResult = GenericError

also,
Graphics g(pDC->m_hDC);
is failed, as lastResult = OutOfMemory

Naturally, GDI grawing using pDC is OK.

How do I manipulate pDC with GDI+?
My environment is Visual Studio 2003 Version 7.1.3091.

If anyone has any suggestions about what I am doing wrong,
it would be greatly appreciated!

Re: How to create GDI+ Metafile from CMetaFileDC?

Hamid_RT31-Aug-06 23:05

Hamid_RT

31-Aug-06 23:05

shinano wrote:
Graphics g(pDC->m_hDC

Whats pDC? CDC or CMetaFileDC

WhiteSky

Re: How to create GDI+ Metafile from CMetaFileDC?

shinano3-Sep-06 14:27

shinano

3-Sep-06 14:27

Thanks,

pDC is a pointer to CMetaFileDC object.
I checked it by debugger.

Re: How to create GDI+ Metafile from CMetaFileDC?

Hamid_RT3-Sep-06 22:12

Hamid_RT

3-Sep-06 22:12

Is your problem solve?if not how to create CMetaFileDC?

WhiteSky

Re: How to create GDI+ Metafile from CMetaFileDC? [modified]

shinano4-Sep-06 13:27

shinano

4-Sep-06 13:27

The method
virtual BOOL OnDraw(CDC* pDC, CSize& rSize);
is called by framework to draw a OLE item to a metafile.
so, CMetaFileDC object is created by framework.
According to MFC library reference "COleServerItem::OnDraw".

-- modified at 20:15 Sunday 17th September, 2006
GDI+ can record metafiles in the EMF and EMF+ formats, but not in the WMF format.
according to "Metafiles in GDI+"
http://msdn2.microsoft.com/en-us/library/zbk7dbtb.aspx

But OnDraw's pDC is Windows Metafile (WMF) .
So, we cannot use GDI+ in COleServerItem::OnDraw. Cry | :((

Clipping child windows

Dave Calkins31-Aug-06 13:44

Dave Calkins

31-Aug-06 13:44

I'm creating a custom control which has a child control. My custom control draws a border and positions the child control.

When the parent control scrolls, it moves the child control to give the appearance of scrolling.

The problem is, when part of the child control goes beyond the edge of the parent control, it overdraws the border.

How can I go about limiting where the child control can draw? Is there some clipping I need to do, adjusting the clipping dynamically as I move the child around?

I've tried a few things with clipping with no luck. Any ideas?

Re: Clipping child windows

mfranco_neto31-Aug-06 18:11

mfranco_neto

31-Aug-06 18:11

I am just beginning at this stuff, but after long hours... here is how I managed to clip child windows:

<br />
..... OnPaint(....)<br />
{<br />
	::GetClientRect(m_hWnd,&test_rect);<br />
	<br />
	::GetClientRect(m_ReadRssWnd,&bk_rect);<br />
<br />
	hRgn2= CreateRectRgn(test_rect.right/3,test_rect.top,test_rect.right-300,test_rect.bottom);<br />
	hRgn = CreateRectRgn(bk_rect.left+200,bk_rect.top,bk_rect.right-100,bk_rect.bottom);<br />
<br />
	hDC2 =::BeginPaint(m_hWnd,&ps2);<br />
	hDC  =::BeginPaint(m_ReadRssWnd,&ps);<br />
<br />
	::SelectClipRgn(hDC2,hRgn2);<br />
	::SelectClipRgn(hDC,hRgn);	<br />
<br />
	::SetTextColor(hDC,RGB(255,255,255));	<br />
	::SetBkColor(hDC,RGB(255,0,0));<br />
<br />
	::FillRect(hDC2,&test_rect,hBr2);	<br />
	::FillRect(hDC,&bk_rect,hBr);<br />
<br />
	::EndPaint(m_ReadRssWnd,&ps);<br />
	::EndPaint(m_hWnd,&ps2);<br />
<br />
	return 0;<br />
}

Now, this is probably not the best solution (or even the right one), but you will get your clip regions...

Now, if you could help me with my problem... just take a look at the message above "EraseBacgnd - mfranco_neto".

Thanks in advance

Mfranco

Problem with CDC:SetMapMode (in Release-Mode) [modified]

AnTri31-Aug-06 12:02

31-Aug-06 12:02

Hey,

I've a MFC-Based DLL calling a special drawing function in another DLL (MFC extended). All works fine in debug-mode. But when I tried to test my DLL in release mode, the program crashes in the line with SetMapMode.

Function in calling DLL (OnPaint):

...<br />
CPaintDC dc(this);<br />
<br />
//dc.SetMapMode(MM_LOMETRIC);       <<<< Works fine here!<br />
PaintSpecialGraphics(&dc);<br />
...

Function in DLL:

int WINAPI PaintSpecialGraphics(CDC *pDC)<br />
{<br />
   ...<br />
   pDC->SetMapMode(MM_LOMETRIC);    <<<< CRASH !!!<br />
   ...<br />
}

Thanx for your help.....

P.S: When I try to call the "PaintSpecialGrafics" from my Application (.exe) all works fine...

-- modified at 18:09 Thursday 31st August, 2006

Stephen Hewitt31-Aug-06 13:47

31-Aug-06 13:47

First I'd make sure you're building the release build with debug info. Follow these steps in MSVC 6:
- Select "Project->Settings...".
- Select the "Release" configuration.
- Select "C/C++" tab.
- Select "General" in the "Category" combo.
- In the "Debug info" combo select "Program Database".
- Select the "Link" tab.
- Select "Debug" in the "Category" in combo.
- Tick "Debug info" and "Separate types" and choose "Microsoft format".
- Select OK.
- Rebuild all.

If you're using a newer version of visual studio you'll have to adjust these steps.

Now reproduce the error are see where the error occurs in the MFC source code; this might give you more chance of understanding what's going wrong.

Steve

Jun Du31-Aug-06 16:50

Jun Du

31-Aug-06 16:50

I suspect it's due to the passing of the DC object between two DLLs, but I can't be sure where exactly the problem is. To narrow it down, check the following:

1) Check the validity of pointer pDC in PaintSpecialGraphics(CDC *pDC);

2) Add thhis code to the calling DLL and see if it works locally:

CDC* pDC = &dc;
pDC->SetMapMode(MM_LOMETRIC);

3) To further test, you could change the function signature from PaintSpecialGraphics(CDC *pDC) to PaintSpecialGraphics(CPaintDC &dc).

Etc.

Best,
Jun

Stephen Hewitt31-Aug-06 19:45

31-Aug-06 19:45

I suspected the same thing but, like you, can't pinpoint the exact problem. That's why I think knowing where things go wrong inside MFC might help.

Perhaps it's possible that different compiler settings were used in the EXE and the DLL and this caused the layout of the CDC class differ.

Or perhaps it's a mixed allocator problem: class CDC in the EXE allocates some data on its heap the the DLL free it on a different heap.

It would probably be a good idea to pass the raw HDC when passing a DC between modules.

Steve

AnTri31-Aug-06 21:43

31-Aug-06 21:43

OK, the error is in the CDC class. The compiler stops in the function OffsetViewportOrg!

Stephen Hewitt31-Aug-06 21:45

31-Aug-06 21:45

Perhaps you can quote the file/line (and MFC version) and paste in some code surrounding the fault.

Steve

AnTri31-Aug-06 23:03

31-Aug-06 23:03

Ok, here is the function where the debugger stops (wingdi.cpp, MFC 7.1, VS2003 SP1):

CPoint CDC::SetViewportOrg(int x, int y)<br />
{<br />
	ASSERT(m_hDC != NULL);<br />
	CPoint point;<br />
<br />
	if (m_hDC != m_hAttribDC)<br />
		VERIFY(::SetViewportOrgEx(m_hDC, x, y, &point));<br />
	if (m_hAttribDC != NULL)<br />
		VERIFY(::SetViewportOrgEx(m_hAttribDC, x, y, &point));<br />
	return point;               <<<<<<<<<<<<<<<<Here stops the debugger !!!???<br />
}

I can't imagine why the debugger/program stops at this line...?

AnTri31-Aug-06 21:24

31-Aug-06 21:24

Thank you for your answer, I tried your recommendation...

1) --> Pointer is valid
2) --> works fine
3) --> ?

Stephen Hewitt31-Aug-06 20:02

31-Aug-06 20:02

I suggest you side step the problem as follows:
1. Change the signature of the DLL function as follows:

int WINAPI PaintSpecialGraphics(HDC hDC);

2. Adjust the implementaion in the DLL so it looks like this:

int WINAPI PaintSpecialGraphics(HDC hDC)
{
    CDC dc;
    dc.Attach(hDC);
    // Do stuff with 'dc' here...
    dc.Detach();
}

3. Make the call like this:

CPaintDC dc(this);
PaintSpecialGraphics(dc);

I suspect you can't use MFC classes across DLL boundries. Here are some possible reasons:
- MFC's handle map implementation.
- Different heaps.
- Different compiler settings in EXE and DLL.

Steve

AnTri31-Aug-06 22:20