C / C++ / MFC

29-Dec-09 3:25

VC6, MFC, XP

Hi - I need to prevent a CView from being closed before a thread operation is complete. The mainframe also has a secondary thread and I've handled that situation by reacting to the WM_CLOSE message. The view, which has it's own worker thread, doesn't seem to get the WM_CLOSE message (even if I put the code in) and reacting to WM_DESTROY in the view is too late to stop it from being closed.

Any suggestions?

Thank you,
Paul

David Crow29-Dec-09 3:31

David Crow

29-Dec-09 3:31

Paul Belikian wrote:
Hi - I need to prevent a CView from being closed before a thread operation is complete.

One way would be to use a CEvent object. When the view is being closed, call WaitForSingleObject() to wait for the event to become signaled. When the thread operation is complete, signal the event.

"One man's wage rise is another man's price increase." - Harold Wilson

"Fireproof doesn't mean the fire will never come. It means when the fire comes that you will be able to withstand it." - Michael Simmons

Paul Belikian29-Dec-09 4:14

29-Dec-09 4:14

Thanks David, that is a good suggestion.

I think my issue is that I'm not sure which (or what) message to hook in the view in order to wait for the event. Blush | :O

The messages I've tried do not stop the view from being closed; for example, if I put a Sleep(5000) call in the view's WM_DESTROY handler, the window is still closed instantly. I need a place where the view will remain open if I delay the WM_xxxxxx message.

I'm doing this in case the user kills the app with the upper 'X' in the application's window ...perhaps I should look into that aspect. This is the only thread related thing I need to clean up. If the user doesn't kill the app while the background process is running (i.e. in the middle of loading a large database), all is well (but when do users wait for anything ? Laugh | :laugh:

), however if they do kill the app, I need to stop the views from being closed before the thread is dead. The threads can be stopped in an orderly manner at any time.

Thanks for your suggestion.

Paul

David Crow29-Dec-09 4:21

David Crow

29-Dec-09 4:21

Paul Belikian wrote:
I think my issue is that I'm not sure which (or what) message to hook in the view in order to wait for the event.

Have you tried responding to WM_CLOSE (i.e., returning 0) in the frame class?

Paul Belikian29-Dec-09 6:08

29-Dec-09 6:08

Mainframe seems to work fine and stops the thread running in the mainframe. However I need to stop the view from closing before the view's thread is stopped (each view has it's own thread and the mainframe has another thread):

void CMainFrame::OnClose()
{
#ifdef _USE_BACKGROUND_THREAD_
	DWORD dwExitCode;
	m_pBackThread->Stop(dwExitCode, 0);
	if(m_pBackThread->GetActivityStatus() != CThread::THREAD_RUNNING) 
	{
		TRACE("Mainframe: Thread Busy, Can't close yet...\n");
		PostMessage(WM_CLOSE); 
	}
	else 
	{ 
		TRACE("Mainframe: Can close now\n");
		m_pBackThread->Stop(dwExitCode);
		
		// Save the current state for tool bars and menus.
		SaveCommandBars(_T("CommandBars"));
		
		// Save the current state for docking panes.
		CXTPDockingPaneLayout layoutNormal(&m_paneManager);
		m_paneManager.GetLayout(&layoutNormal);
		layoutNormal.Save(_T("NormalLayout"));
		
		CMDIFrameWnd::OnClose();
   } 
#else
	// Save the current state for tool bars and menus.
	SaveCommandBars(_T("CommandBars"));
	
	// Save the current state for docking panes.
	CXTPDockingPaneLayout layoutNormal(&m_paneManager);
	m_paneManager.GetLayout(&layoutNormal);
	layoutNormal.Save(_T("NormalLayout"));
	
	CMDIFrameWnd::OnClose();
#endif

}

JudyL_MD29-Dec-09 16:50

JudyL_MD

29-Dec-09 16:50

The mainframe should know all its child views. Create a function in each view that the mainframe calls from its OnClose which can wait / allow / disallow the close.

Judy

Be wary of strong drink. It can make you shoot at tax collectors - and miss.
Lazarus Long, "Time Enough For Love" by Robert A. Heinlein

Paul Belikian29-Dec-09 17:37

Ideas for an embedded interactive console?

29-Dec-09 17:37

Hello Judy, yes, thank you for the suggestion. I actually did go that route using the DocTemplate to find all the views that I needed to check before closing. I chose this method because I also have multiple types of documents in the app - here is the code: forgive the mess, I'm self-taught Blush | :O

void CMainFrame::OnClose()
{
#ifdef _USE_CMC6INVOICE_THREAD_
	
	POSITION pos, posView;
		
	pos = theApp.m_pCmc6InvoiceDocTemplate->GetFirstDocPosition();
	while(pos != NULL)
	{
		CDocument *pDoc = theApp.m_pCmc6InvoiceDocTemplate->GetNextDoc(pos);
		if(pDoc!= NULL)
		{
			posView = pDoc->GetFirstViewPosition();
			while(posView != NULL)
			{
				CView * pView = pDoc->GetNextView(posView);
				if(pView->IsKindOf(RUNTIME_CLASS(CCMC6InvoiceView)))
				{
					CCMC6InvoiceView * pInv = (CCMC6InvoiceView *) pView;
					if(pInv->m_clsInvoice->m_pThread != NULL)
					{
						if(pInv->m_clsInvoice->m_pThread->GetActivityStatus() == THREAD_NOTPREPARED_TO_TERMINATE) 
						{
							TRACE("Mainframe: OnClose() ->CMC6InvoiceView Thread Busy, Can't close yet...\n");
							Sleep(200);
							PostMessage(WM_CLOSE); 
							return;
						}
					}
				}
			}
		}
	}
#endif
#ifdef _USE_BACKGROUND_THREAD_
	DWORD dwExitCode;
	m_pBackThread->Stop(dwExitCode, 0);
	if(m_pBackThread->GetActivityStatus() == THREAD_NOTPREPARED_TO_TERMINATE) 
	{
		TRACE("Mainframe: OnClose() ->BackProcess Thread Busy, Can't close yet...\n");
		Sleep(200);
		PostMessage(WM_CLOSE); 
	}
	else 
	{ 
		TRACE("Mainframe: OnClose() ->Can close now\n");
		m_pBackThread->Stop(dwExitCode);
		
		// Save the current state for tool bars and menus.
		SaveCommandBars(_T("CommandBars"));
		// Save the current state for docking panes.
		CXTPDockingPaneLayout layoutNormal(&m_paneManager);
		m_paneManager.GetLayout(&layoutNormal);
		layoutNormal.Save(_T("NormalLayout"));
		
		CMDIFrameWnd::OnClose();
   }
#else
	// Save the current state for tool bars and menus.
	SaveCommandBars(_T("CommandBars"));
	// Save the current state for docking panes.
	CXTPDockingPaneLayout layoutNormal(&m_paneManager);
	m_paneManager.GetLayout(&layoutNormal);
	layoutNormal.Save(_T("NormalLayout"));

	CMDIFrameWnd::OnClose();
#endif
}

z33z29-Dec-09 3:24

z33z

29-Dec-09 3:24

I want to create a console like dialog, I was thinking like in a multi-line edit boxt, but I don't know how so I need some ideas to start with.

It should work like a "real" console, where you only can write at the prompt, only delete what you just have written, but not yet executed and so on.

Many games have a console like this, to send messages etc, maybe there's some code to start with?

What the result should be is an interactive console for Python, but intergrated in my application as a modeless window or a dialog. Python is easy to embed with, for example PyRun_InteractiveLoop, reading and writing to stdin/out.

Any ideas how this can be archived?
Thanks!

Re: Ideas for an embedded interactive console?

raja jamwal31-Dec-09 8:30

raja jamwal

31-Dec-09 8:30

Well you can paint it back bg with CTL_COLORSTATIC notification message, you can use keyboard handler to do pretty cool stuff or you can simply trace for keywrds like record for keyboard msgs in wnd proc, and use gettickcount know make if a word is typed.then you can simply use GetDlgItemText to get text then append, i recommend use sstream.h for string formatting. then simply set the text to edit box with setdlgitemtext

Is there any way to execute XQuery through MFC or C++

A&Ms29-Dec-09 3:06

A&Ms

29-Dec-09 3:06

Hi,
Is there any way to execute XQuery through MFC Code, I know How to use MSXML.DLL to load xml documents and navigate the XML document But I am looking for a method like ExecuteSQL("") to execute my XQuery statements?

When my article will be publish?How many days in general?

JunWang16329-Dec-09 0:29

JunWang163

29-Dec-09 0:29

When my article will be publish?How many days in general?Who have the right to publish the article?

Wrong forum.

CPallini29-Dec-09 0:47

CPallini

29-Dec-09 0:47

The Lounge [^] is possibly more appropriate.
Smile | :)

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-- Alfonso the Wise, 13th Century King of Castile.

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-- Iain Clarke

[My articles]

creating dbf file and reading info from dbf

kir_MFC29-Dec-09 0:18

kir_MFC

29-Dec-09 0:18

HI,
In my application I need to create a employee.dbf file and reading that employee information into employee structure and filling that information into emplyee dialog box.

kir_MFC

KingsGambit29-Dec-09 0:36

KingsGambit

29-Dec-09 0:36

What is a dbf file? Is it a database file?

kir_MFC29-Dec-09 2:05

kir_MFC

29-Dec-09 2:05

yes

kir_MFC

mav@octaval29-Dec-09 2:10

mav@octaval

29-Dec-09 2:10

Are you talking about the ancient dBase database file?

--

Si dos montan un caballo, uno debe ir detrás.

dxlee29-Dec-09 3:21

dxlee

29-Dec-09 3:21

There are information on dbf file structures available on the web. I suggest you do a search to find the info.

David Crow29-Dec-09 3:34

David Crow

29-Dec-09 3:34

ODBC would probably be the easiest. If you are using MFC, check out the CRecordset and CDatabase classes.