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Hi Mark. Thanks.
Appreciated for your share. It really helps me understand IOCP and other asnc IO operation.
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I have an SDI app, where I want to serialize an versionable object, of CData class :
class CData : public CObject
{
DECLARE_SERIAL(CData)
public:
CData();
virtual ~CData();
virtual void Serialize(CArchive& ar);
BOOL ReadDocumentFromDisk();
BOOL WriteDocumentToDisk();
};
and here is implementation code :
IMPLEMENT_SERIAL(CData, CObject, VERSIONABLE_SCHEMA | 1)
CData::CData()
{
}
CData::~CData()
{
}
void CData::Serialize(CArchive& ar)
{
CObject::Serialize(ar);
try
{
if(ar.IsLoading())
{
TRACE("Loading : objectschema - %d\n",ar.GetObjectSchema());
int n = 0;
ar >> n;
TRACE("n is %d\n",n);
}
else {
int x = 456;
ar << x;
}
}
catch(CFileException* pFileException)
{
pFileException->ReportError();
pFileException->Delete();
}
}
BOOL CData::ReadDocumentFromDisk()
{
CFile file;
CString sFile;
CFileException FileException;
::GetModuleFileName(NULL,sFile.GetBuffer(255),255);
sFile.ReleaseBuffer();
sFile = sFile.Left(sFile.ReverseFind('\\') + 1);
sFile += _T("Default.tse");
if(! file.Open(sFile,CFile::modeRead,&FileException))
{
return FALSE;
}
CArchive ar(&file,CArchive::load);
Serialize(ar);
return TRUE;
}
BOOL CData::WriteDocumentToDisk()
{
CFile file;
CString sFile;
CFileException* pFileException = NULL;
::GetModuleFileName(NULL,sFile.GetBuffer(255),255);
sFile.ReleaseBuffer();
sFile = sFile.Left(sFile.ReverseFind('\\') + 1);
sFile += _T("Default.tse");
if(! file.Open(sFile,CFile::modeCreate | CFile::modeWrite,pFileException))
{
return FALSE;
}
CArchive ar(&file,CArchive::store);
Serialize(ar);
return TRUE;
}
and from somewhere in CMyView class, I call :
void CTestSerializeView::OnHelpLoad()
{
CData data;
data.ReadDocumentFromDisk();
}
void CTestSerializeView::OnHelpStore()
{
CData data;
data.WriteDocumentToDisk();
}
although serialization of integer variable is good, I always get version -1 of CData object :
<br />
TRACE("Loading : objectschema - %d\n",ar.GetObjectSchema()); <br />
what I'm doing wrong ?
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Debug each step and see where the value is coming from.
==============================
Nothing to say.
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Hello,
I have a class that doesn't connect to a dialog or window
and I need to do some operations on timer but the timers works only with dialogs ,
does anyone know another way I do it?
thank
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You can have a thread running the Sleep API. After a specified interval of time it becomes active, performs it's task and sleep's again for the specified duration.
That is somewhat similar to what a timer does.
You talk about Being HUMAN. I have it in my name
AnsHUMAN
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Thanks for the answer,
But the operations that I need to perform on the timer
shuld have an approach to the data members and member Functions of the class ,
can I do it with threads?
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No, not thread safe at all.
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Could make it threadsafe with Mutexes[^]
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Yeah but consider what he wants to do... if he's already using the WinAPI, might as well use the Win timers. Otherwise we'll have to answer a bunch of questions regarding mutexes next [joke  ].
modified 25-Oct-11 16:28pm.
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Just use the win 32 set timer method: http://msdn.microsoft.com/en-us/library/windows/desktop/ms644906(v=vs.85).aspx[^]
Dont forget, MFC just wraps the Win32 API, and even then not all of it (there is a lot of rich unctionality there not available in MFC), and pretty much all MFC functions have a function of the same name in the win32API.
Most of these win32 funcs take a window handle as the first param, and thats generally the only difference between them, and their MFC counterpart, since the MFC one generally calls itself.
So for example the win32 MessageBox() func has a HWND as the first partam, then all the rest are the same as MFC.
You can also call the win32API directly form MFC code. Just use the global namespce operator :: before each call ie:
::MessageBox(hWnd, txt, msg, MB_OK);
You can get window handles for other processes/wondows easilly too. FindWindow() returns a HWND. Its params are eityher the class of the window, or its text (in the title bar).
You can use this to send or post messages, such as WM_COMMAND ones to another window.
Like I say, there is a lot you can do outside of MFC. (Window hooks are particularly interesting things. Very very powerfull.) 
==============================
Nothing to say.
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Thanks a lot,
As I understand I need to use SetTimer() and to give it an handle to window but
the class is not connected to a dialog so what the hWnd that I need to pass?
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Timers have nothing to do with dialogs, they operate on any Window. The issue of passing a handle to the window is so that the Windows framework knows where to post the WM_TIMER message that gets raised when the timer expires. If you do not have a Window to connect the timer to then SetWaitableTimer()[^] may be able to help you.
Unrequited desire is character building. OriginalGriff
I'm sitting here giving you a standing ovation - Len Goodman
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aangerma wrote: so what the hWnd that I need to pass?
The one to your dialog/app window that handles WM_TIMER.
As suggested you can get this handle with a FindWindow() specifying the title text. Or you can provide it form the fialog itself, I forget the func, something like GetSafeHwnd() or some such, but there is one for a dialog to get its own handle.
Like I say, hunt through the win32 API. You will find what you need there.
==============================
Nothing to say.
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SetTimer[^] has a fourth parameter, an application defined callback function. Use that and set the HWND to NULL.
Independent ACN Business Owner- Check out the possibilities for your future!
- Financial independance
- Full time or Part time
- In more than 20 countries through North America, Europe, Asia and the Pacific
- Featuring the ACN IRIS 5000 video phone. See the person you are talking to.
Within you lies the power for good - Use it!
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He might find that difficult to specify a class member as a call back function. But yes, it is doable (and one of the reasons I prefer C, OK, you need to be a good programmer, but you can do what you want)
==============================
Nothing to say.
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Now why didn't I think of that; good answer.
Unrequited desire is character building. OriginalGriff
I'm sitting here giving you a standing ovation - Len Goodman
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On reflection I decided to test this and it does not work without any windows, as there is nothing to process the WM_TIMER message, which is used by the default handler to invoke the callback routine.
Unrequited desire is character building. OriginalGriff
I'm sitting here giving you a standing ovation - Len Goodman
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I would be interested to see your test code. I have no problems using a timer callback procedure.
Independent ACN Business Owner- Check out the possibilities for your future!
- Financial independance
- Full time or Part time
- In more than 20 countries through North America, Europe, Asia and the Pacific
- Featuring the ACN IRIS 5000 video phone. See the person you are talking to.
Within you lies the power for good - Use it!
|
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Looking at it further, the app does not need a window, but if there is no window then the thread needs a message loop.
Independent ACN Business Owner- Check out the possibilities for your future!
- Financial independance
- Full time or Part time
- In more than 20 countries through North America, Europe, Asia and the Pacific
- Featuring the ACN IRIS 5000 video phone. See the person you are talking to.
Within you lies the power for good - Use it!
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PJ Arends wrote: the thread needs a message loop.
That's the issue; even with a callback the timer signals by posting a WM_TIMER message.
Unrequited desire is character building. OriginalGriff
I'm sitting here giving you a standing ovation - Len Goodman
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I have a few apps like that (mostly system services) so at the end of "main()" (or whatever you use), stick code like this:
static MSG msg;
while (GetMessage(&msg, NULL, 0, 0))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}
return(msg.wParam);
It doesn't hurt to sit in this loop while the other threads do their job and it allows them to post WM_CLOSE messages to run-down the process if necessary. Other standard messaging things works, including timers.
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Thanks for the reply,
can you give me more details how to use it?
How can I know which message I Received by msg?
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This is the standard windows message pump, it only causes windows messages to get processed for apps that are not "dialog based". You don't modify this code in any way nor look at the message in that loop. The "dispatch" is done by windows to the proper messsage handler. If you have dialogs, windows does this for you.
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Can you give me exmple how to write a messsage handler ,
I did it only with the class wizard of mfc,
and this is the first time I need to add a timer
to a class that don't connected to any window,
even if I creat a fictive window like dialog box the SetTimer(...)
works only if the dialog is opened by DoModal.
thanks
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