Re: writing to a port - C / C++ / MFC Discussion Boards

Arman S.4-Jul-07 5:19

4-Jul-07 5:19

On the first call [or so] to OnSize the child windows have not been created yet. In other words, their HWNDs are not valid. Perheps this is what causes the assertion failure. Try to have smth like so;

CStatic *pStatic;
pStatic= (CStatic*) GetDlgItem(IDC_MYSTATIC);
if (NULL != pStatic)
{
// do anything here
}

In this way you will skip the first time call to OnSize.

In general, using GetDlgItemis not a good idea. Instead, let the wizard define CStatic c_myStatic member-variable. In this case the code will turn into this one;

if (NULL != c_myStatic.GetSafeHwnd())
{
// do anything here
}

--
=====
Arman

Re: OnSize Assertion Error

sdancer754-Jul-07 22:56

sdancer75

4-Jul-07 22:56

Hi Arman,

I suppose you have right. I did not tested since i have changed my code and i placed all code to CalcDynamicLayout(int nLength, DWORD dwMode) and it works.

Thank you for your reply,

Regards,

sdancer75

Re: OnSize Assertion Error

Hamid_RT4-Jul-07 19:28

Hamid_RT

4-Jul-07 19:28

I agree with Arman maybe your error is of first call.

WhiteSky

need your suggestion for data expression

includeh104-Jul-07 4:56

includeh10

4-Jul-07 4:56

in my progarm (special to deal with data), i need good expressions for 2,4,8,16 based integers.

for example, in c++, we use 0x... to stand for 16 based data.

so, expressions i try to use are:

0b... (2 based)
0f... (4 based)
0o... (8 based)
0x... (16 based)

but i am afraid that expressions above are not good.
i hope i can use common or popular expressions.

do you know expressions which are accepted already by people for different based integers?

Re: need your suggestion for data expression

David Crow5-Jul-07 3:25

David Crow

5-Jul-07 3:25

Base-2 and base-8 numbers already have a known prefix. Why the change? What exactly are you trying to do?

"A good athlete is the result of a good and worthy opponent." - David Crow

"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne

writing to a port

lovneet4-Jul-07 4:40

lovneet

4-Jul-07 4:40

hey!
m working on a code where in i have to write to a board. the system and the board are connected via UART. m using VC++. the problem is that the moment i try to write a character the system hangs. here is a part of the code -

void CserialportthingieDlg::OnBnClickedWrite()
{
UpdateData(TRUE);
size_t size;
size = strlen(m_sshwwrite);//m_sshwwrite is he variable associated with the editbox
int i;
i=size-1;
asd->WriteByte(m_sshwwrite[i]);//asd is an instance of the class SerialCom where in i writebyte has been defined.

}

the definition of writebyte is --

BOOL CSerialCom::WriteByte(BYTE bybyte)
{
iBytesWritten=0;
if(WriteFile(hComm,&bybyte,1,&iBytesWritten,NULL)==0)
return false;
else
return true;
}

please let me know if any thing is wrong with the code or tell me a better way.
thanks a lot!

regards
lovy

Re: writing to a port

CPallini4-Jul-07 4:48

CPallini

4-Jul-07 4:48

How do you set the serial port timeouts (remember: WriteFile is a blocking call)?
Smile | :)

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

Re: writing to a port

lovneet4-Jul-07 6:17

lovneet

4-Jul-07 6:17

actually i had set some arbit time out. Big Grin | :-D

now even when i restored it to the default value the system still hangs!
help me out!

thanks

regards
lovy

Re: writing to a port

CPallini4-Jul-07 9:07

CPallini

4-Jul-07 9:07

Post the relevant code (i.e. port open, DCB definition, etc..)
Smile | :)

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

Re: writing to a port

David Crow5-Jul-07 3:27

David Crow

5-Jul-07 3:27

If WriteFile() is failing, call GetLastError() to find out why.

"A good athlete is the result of a good and worthy opponent." - David Crow

"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne

Re: writing to a port

khan++5-Jul-07 3:49

khan++

5-Jul-07 3:49

May be you are setting the wrong kind of handshaking. If you are setting hardware handshake, unless the board on the other end sets the relevant lines in the port, the WriteFile will wait until the port timeout (if I remember it correctly).

There are variables in the DCB structure that need to be set for setting the handshake mode(None, Software, or Hardware).

Also you could check if the board is working by trying it with HyperTerminal first with the correct Handshaking.

this is this.

lower and higher part of a variable

Dobromir Dimitrov4-Jul-07 4:32

Dobromir Dimitrov

4-Jul-07 4:32

Hello. I am new to MFC and C++ in general. I am interested in how to get the lower and higher parts of a DWORD variable?

Re: lower and higher part of a variable

Matthew Faithfull4-Jul-07 4:40

Matthew Faithfull

4-Jul-07 4:40

I guess you're looking for the HIWORD and LOWORD macros. MSDN docs are here[^]

Nothing is exactly what it seems but everything with seems can be unpicked.

Re: lower and higher part of a variable

CPallini4-Jul-07 4:42

CPallini

4-Jul-07 4:42

Have a llot at LOWORD and similar macros on MSDN http://msdn2.microsoft.com/en-us/library/ms632659.aspx[^].
Smile | :)

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

Error sound when closing application

Twister3364-Jul-07 2:23

Twister336

4-Jul-07 2:23

After I switched from VS2003 to VS2005 the Windows error sound comes up when I close my application but there's no error message.

The only changes I made in the code are the ones required to make it VS2005 compatible.

Re: Error sound when closing application

Programm3r4-Jul-07 3:10

Programm3r

4-Jul-07 3:10

Are you sure there is no MessageBeep() in your code ?

Just guessing

Regards,

The only programmers that are better that C programmers are those who code in 1's and 0's Green Alien | [Alien]

Programm3r
My Blog: ^_^

Re: Error sound when closing application

Mark Salsbery4-Jul-07 7:18

Mark Salsbery

4-Jul-07 7:18

That's Microsoft's way of making your application more multimedia robust!

Smile | :)

If you run in the debugger, do you see any exception/error/assert messages in the Output window
during shutdown?

Mark

Mark Salsbery
Microsoft MVP - Visual C++

"Go that way, really fast. If something gets in your way, turn."

Re: Error sound when closing application

Hamid_RT4-Jul-07 19:30

Hamid_RT

4-Jul-07 19:30

Can you more explain about your program?

WhiteSky

Re: Error sound when closing application

Twister3366-Jul-07 23:57

Twister336

6-Jul-07 23:57

I found the problem. It was a third party library which caused it.
I've got a new version of that library and now the problem is fixed.

Thanks everyone! Smile | :)

How to Reduce Desktop Size

vikrant kpr4-Jul-07 2:22

vikrant kpr

4-Jul-07 2:22

Hello Friends
I have seen few toolbars that reduce size of desktop window & locate them on the top.
Any idea how they do that?
In case i try GetDeskTopWindow & do a MoveSize it does not works?
Regards

Re: How to Reduce Desktop Size

Nibu babu thomas4-Jul-07 3:19

Nibu babu thomas

4-Jul-07 3:19

vikrant kpr wrote:
I have seen few toolbars that reduce size of desktop window & locate them on the top.
Any idea how they do that?

Look up SHAppBarMessage.

Nibu thomas
A Developer

Code must be written to be read, not by the compiler, but by another human being.

http:\\nibuthomas.wordpress.com

Re: How to Reduce Desktop Size

Hamid_RT4-Jul-07 19:37

Hamid_RT

4-Jul-07 19:37

See this[^] article does helpful for you?

WhiteSky

How to change place of activex control at run time

adityarao314-Jul-07 1:45

adityarao31

4-Jul-07 1:45

I am having windows media player as activex control
in my application. I am trying to use create method
for same but I am not able to use. Some where I am missing something.
CWMPPlayer4 m_lplayer;

void CApl2IEDlg::OnButton1()
{
RECT lprect;
lprect.bottom = 0;
lprect.left = 0;
lprect.right = 100;
lprect.top = 100;
RegisterWindow();
CWMPPlayer4 cwmp;
cwmp.Create(m_lplayer,mediaclass,0,lprect,(CWnd*)m_hWnd,0,NULL);

}

LRESULT FAR PASCAL WndProc(HWND hWnd, UINT Message, WPARAM wParam, LPARAM lParam)
{
return (DefWindowProc(hWnd, Message, wParam, lParam));
}

void CApl2IEDlg::RegisterWindow()
{

mediaclass = "mediaclass";
WNDCLASS wndclass;
wndclass.style = CS_DBLCLKS | CS_HREDRAW | CS_VREDRAW;
wndclass.lpfnWndProc = WndProc;
wndclass.cbClsExtra = 0;
wndclass.cbWndExtra = 0;
wndclass.hInstance = AfxGetInstanceHandle();
wndclass.hIcon = LoadIcon(NULL,_T(""));
wndclass.hCursor = LoadCursor(NULL,IDC_ARROW);
wndclass.lpszMenuName = NULL;
wndclass.lpszClassName = mediaclass;

}

|| Lust Causes Sorrow ||

Re: How to change place of activex control at run time

Mark Salsbery4-Jul-07 7:31

Mark Salsbery

4-Jul-07 7:31

It looks like you might be using the wrong Create() for an activex control.

Make sure you're calling a Create() method from the wrapper class for the control.

To create the wrapper class (if you haven't already), you can use Project Menu/Add Class/MFC/
MFC Class from ActiveX Control.

Mark

Mark Salsbery
Microsoft MVP - Visual C++

"Go that way, really fast. If something gets in your way, turn."

Re: How to change place of activex control at run time

shivditya4-Jul-07 7:39

shivditya

4-Jul-07 7:39

I am using create method which is there in .cpp file which gets loaded once we insert control from registered controls. We can use other methods, Cant we use create?
Anyway I will try your suggestion tomorrow. But every time I try to create window for control this problem comes. I am really fed up of ActiveX controls but I have to use.

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