Creating a thread - C / C++ / MFC Discussion Boards

Smith#16-Dec-05 0:29

16-Dec-05 0:29

fisrt of all thanks for your patience,
for the first time i think i've understood whats a callback.
See here

LRESULT CALLBACK WndProc(HWND hwnd, UINT msg,WPARAM wParam, LPARAM lParam)

as i've read,WndProc processes all the messages send by the applications. right? so a message "coming" makes an event which inturn calls this CALLBACK wndProc right? am i right?

regards,
Rookie
Installing MFC...2% complete

Re: i'm dumb

Russell^'16-Dec-05 0:33

Russell^'

16-Dec-05 0:33

Rokiee wrote:
am i right?

Yes.

Have a nice code day Wink | ;)

Re: i'm dumb

Smith#16-Dec-05 0:37

Smith#

16-Dec-05 0:37

can i come with another dumb question?? later? Unsure | :~

regards,
Rookie
Installing MFC...2% complete

Re: i'm dumb

Cedric Moonen16-Dec-05 0:42

Cedric Moonen

16-Dec-05 0:42

Rokiee wrote:
can i come with another dumb question??

Of course you can. This is the purpose of this message board Smile | :)

Re: i'm dumb

Smith#16-Dec-05 2:33

Smith#

16-Dec-05 2:33

so nice of you Smile | :)

regards,
Rookie
Installing MFC...2% complete

Re: i'm dumb

Russell^'16-Dec-05 0:48

Russell^'

16-Dec-05 0:48

Of course!!! Big Grin | :-D

The problem could be only this:
Am I a good programmer, to solve your question? Sigh | :sigh:

We will see.
Bye

Have a nice code day Wink | ;)

Re: i'm dumb

Ravi Bhavnani16-Dec-05 10:51

Ravi Bhavnani

16-Dec-05 10:51

Rokiee wrote:
another dumb question??

The only dumb question is the one that's never asked. So ask away! Smile | :)

We're here to help.

/ravi

My new year's resolution: 2048 x 1536
Home | Music | Articles | Freeware | Trips
ravib(at)ravib(dot)com

Creating a thread

laiju15-Dec-05 23:54

laiju

15-Dec-05 23:54

Following is a funciton where I am calling a thread
void CMyView::OnInitialUpdate()
{
...
AfxBeginThread(Thread_ScanConnectionState, m_sComPort, THREAD_PRIORITY_NORMAL, NULL, NULL, NULL);
...
}

//Foll is the thread definition
UINT CMyView::Thread_ScanConnectionState(LPVOID pParam)
{
CString sComPort;
sComPort = static_cast<lpcstr> (pParam);
return 1;
}
The declaration of the thread in the class header of CMyView is as below.
UINT Thread_ScanConnectionState( LPVOID pParam );

I get the compilation error as given below
error C2665: 'AfxBeginThread' : none of the 2 overloads can convert parameter 1 from type 'UINT (LPVOID)'
c:\Program Files\Microsoft Visual Studio .NET 2003\Vc7\atlmfc\include\afxwin.h(4105): could be 'CWinThread *AfxBeginThread(AFX_THREADPROC,LPVOID,int,UINT,DWORD,LPSECURITY_ATTRIBUTES)'
c:\Program Files\Microsoft Visual Studio .NET 2003\Vc7\atlmfc\include\afxwin.h(4108): or 'CWinThread *AfxBeginThread(CRuntimeClass *,int,UINT,DWORD,LPSECURITY_ATTRIBUTES)'
while trying to match the argument list '(overloaded-function, CString)'
Please let me know the error.

laiju

Re: Creating a thread

Arman S.16-Dec-05 0:11

Arman S.

16-Dec-05 0:11

Hi,

First: AfxBeginThread takes a static function pointer. Yours is not a static function. IOW, make Thread_ScanConnectionState static.

Second: In the func nody you typed 'static_cast(pParam)': incorrect.
The correct is:
sComPort = static_cast<cstring> (pParam);

Third: Do not do extra typing: AfxBeginThread's default parameters work fine.
You need not pass THREAD_PRIORITY_NORMAL or the NULLs. Smile | :)

--
======
Arman

Re: Creating a thread

Arman S.16-Dec-05 0:21

Arman S.

16-Dec-05 0:21

Second: In the func nody you typed 'static_cast(pParam)': incorrect.
The correct is:
sComPort = static_cast (pParam);

Sorry, it seems the editor doesn't love static_cast's signature Smile | :)

--
======
Arman

Re: Creating a thread

toxcct16-Dec-05 0:35

toxcct

16-Dec-05 0:35

Arman Z. Sahakyan wrote:
Sorry, it seems the editor doesn't love static_cast's signature

the editor is just html, so don't use html tags...
<> are interpreted.
if you don't want it to, check the Ignore HTML tags in this message (good for code snippets) checkbox or use < > codes instead...

TOXCCT >>> GEII power
[toxcct][VisualCalc 2.20][VisualCalc 3.0]

Re: Creating a thread

Arman S.16-Dec-05 1:02

Arman S.

16-Dec-05 1:02

Thanks.

--
======
Arman

Re: Creating a thread

laiju16-Dec-05 1:02

laiju

16-Dec-05 1:02

Thanx for the info. But i didnt know that the THREAD func needs to be static.Thanx anyway

laiju

Re: Creating a thread

Arman S.16-Dec-05 1:08

Arman S.

16-Dec-05 1:08

Note that thread function must be either global or a static class-method.
I wanted to say it cannot be a non-static class-method as you were using.

--
======
Arman

Re: Creating a thread

toxcct16-Dec-05 1:49

toxcct

16-Dec-05 1:49

when a function is a class member (except static ones), it receives an implicit parameter which is the this pointer. this implicit parameter changes the signature of what you see of your function in design mode...

for instance :

class A {
  public:
    void foo(int);
};

just considering the case of this function, its signature is in fact :

void A::foo(A*, int);

so, as AfxBeginThread() receives a function pointer, this parameter must implement a particuliar function signature, it must be exactly as you defined it. this is why your function must be global, or at least static (because static members don't know specific instances of a class - they are also known as class function)...

hope that helps...

TOXCCT >>> GEII power
[toxcct][VisualCalc 2.20][VisualCalc 3.0]

ActiveX programming

a_david12315-Dec-05 23:24

a_david123

15-Dec-05 23:24

Please suggest beginner level tutorial(s) for ActiveX programming in VC++
thanks

david

bmp's

V.15-Dec-05 22:28

15-Dec-05 22:28

Hi guys,

I've been out for a while and now I have to adapt a program for an interview to test my skills. It's all bmp's, so opening, rotating, changing colors etc...

I've been searching a bit, but of course MSDN isn't helping and I couldn't really find something on CP either.

Can anybody point out a good tutorial or something?
I do know how bmp's are built (a header and then the colors row by row)

I'm really confused with CBitmap and HBITMAP (and if I'm not mistaken you've got a Bitmap and BITMAP too?)

tnx!
(PS: my interview is on monday so I've got a lot of studying to do)

No hurries, no worries.

Re: bmp's

ThatsAlok15-Dec-05 23:54

ThatsAlok

15-Dec-05 23:54

V. wrote:
Can anybody point out a good tutorial or something?

You will find this page intresting :-
http://priyank.in/formats.php[^]

"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

Re: bmp's

V.16-Dec-05 0:01

16-Dec-05 0:01

tnx man,

It's a bit basic 'cause I did work on bmp's, but that was some time ago. (I forgot they saved it backwards D'Oh! | :doh:

)
So your info was idd useful...

tnx

No hurries, no worries.

how to use "resource only dll"

kotiramkoteswararao15-Dec-05 22:23

kotiramkoteswararao

15-Dec-05 22:23

hi,

i have created one "resource only dll" . in that dll,i have stored some GIF files. Here i need some information,

How can i use those reources in application and how can i use those GIF files in my application and display them.

regards,
RamakakoteswaraRao

Spend every minute for success

Re: how to use &amp;quot;resource only dll&amp;quot;

David Crow16-Dec-05 3:05

David Crow

16-Dec-05 3:05

If the images were BMP format instead, you could use:

HINSTANCE hLibrary = Loadlibrary("MyResources.dll");
HANDLE hImage      = LoadImage(hLibrary, "MyImage" ...);

GIF images can still be loaded from the DLL, but with a bit more code:

HRSRC hResource  = FindResource(hLibrary, "MyImage", RT_RCDATA);
HRSRC hLoaded    = LoadResource(hLibrary, hResource);
char *lpResource = LockResource(hLoaded);
// now you can do something with the GIF bytes pointed to by lpResource

"Take only what you need and leave the land as you found it." - Native American Proverb

Process-wide API spying - Source Code?

devvvy15-Dec-05 22:01

devvvy

15-Dec-05 22:01

Any one has source code for this article? Process-wide API spying - an ultimate hack by Anton Bassov
?

Thanks in advance.

Norman Fung

help me pls

Petiao15-Dec-05 21:56

Petiao

15-Dec-05 21:56

i willing to do a system that can using 1 mouse and 1 keyboard to control another pc's mouse and keyboard, now i dun have any idea, who can help me pls?

nick

Re: help me pls

toxcct15-Dec-05 22:45

toxcct

15-Dec-05 22:45

trojan like ?
Poke tongue | ;-P

TOXCCT >>> GEII power
[toxcct][VisualCalc 2.20][VisualCalc 3.0]

Re: help me pls

Eytukan16-Dec-05 2:24

Eytukan

16-Dec-05 2:24

unplug the mouse from the first computer then plug them into the other computer. this way you can control the other system. Cool | :cool:

"But your mind is very complex, very tricky. It makes simple things complicated. -- that's its work. And for centuries it has been trained for only one thing: to make things so complicated that your life becomes impossible."- Osho

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