Re: OnInitialUpdate() never gets entered - C / C++ / MFC Discussion Boards

Re: Sending A Variable to another computer.

David Crow30-Mar-06 10:56

30-Mar-06 10:56

The C in DC stands for context, which infers that it is only meaningful in a specific context for a specific device. Sending that to another computer makes no sense. You can, however, send the screen data in chunks to the other computer. The Terminal Services API might be required, but I really don't know for sure.

"Let us be thankful for the fools. But for them the rest of us could not succeed." - Mark Twain

"There is no death, only a change of worlds." - Native American Proverb

Can't find clipboard is busy error

Harrier30-Mar-06 9:46

Harrier

30-Mar-06 9:46

I'm trying to track down an error where a message box comes up "Attempt to open busy clipboard window, OK to resume". Anyone see this before??

Thanks - harrier

Re: Can't find clipboard is busy error

David Crow30-Mar-06 9:51

David Crow

30-Mar-06 9:51

What are you doing that causes this message to appear?

"Let us be thankful for the fools. But for them the rest of us could not succeed." - Mark Twain

"There is no death, only a change of worlds." - Native American Proverb

Re: Can't find clipboard is busy error

Harrier30-Mar-06 10:06

Harrier

30-Mar-06 10:06

This is partly the problem, no clear repro on it. When it happens it's frequent but not consistent. Most of the time it's the main app window becoming the active window.

harrier

Re: Can't find clipboard is busy error

David Crow30-Mar-06 10:32

David Crow

30-Mar-06 10:32

So do you have code someplace that it interacting with the clipboard?

"Let us be thankful for the fools. But for them the rest of us could not succeed." - Mark Twain

"There is no death, only a change of worlds." - Native American Proverb

Re: Can't find clipboard is busy error

Harrier30-Mar-06 10:44

Harrier

30-Mar-06 10:44

Probably. Not my code. Inherited. I try to find a repro before digging through code. I've googled all sorts of keywords and only found one non-english site with the same error message. Now here I am hoping someone who actually has written code for the clipboard knows what this means. I could try looking through code but I don't know what I'm looking for.

- Harrier

OnInitialUpdate() never gets entered

ns30-Mar-06 9:20

30-Mar-06 9:20

Here's the code I added to my CDialog

// Overrides
	// ClassWizard generated virtual function overrides
	//{{AFX_VIRTUAL(CTargetInfo)
	public:
	virtual void OnInitialUpdate(); // called first time after construct

and

void CTargetInfo::OnInitialUpdate() 
{


	if(NULL != m_listTgtInfo.GetSafeHwnd())
	{
		(void)m_listTgtInfo.SetExtendedStyle( LVS_EX_FULLROWSELECT );
		m_listTgtInfo.InsertColumn(0,"Keywords",LVCFMT_LEFT,800);
		//m_keysListBox.SetColumnWidth(0, LVSCW_AUTOSIZE_USEHEADER);

		m_listTgtInfo.SetExtendedStyle(LVS_EX_CHECKBOXES);
		m_listTgtInfo.InsertColumn(1,"Options",LVCFMT_LEFT,800);
	}

}

It nevers enters the OnInitialUpdate

The way I am creating the dialog is

                   m_tgtInfo = new CTargetInfo(this);
if(!m_tgtInfo) return CDialog::OnCommand(wp, lp);
m_tgtInfo->Create(IDD_DLGTGTINFO, (CWnd*)this);
m_tgtInfo->ShowWindow(SW_SHOW);

Is there something else I need to do?
thanks,
sb

Re: OnInitialUpdate() never gets entered

David Crow30-Mar-06 9:53

David Crow

30-Mar-06 9:53

OnInitialUpdate() is for a view, not a dialog. Override OnInitDialog() instead.

ns wrote:
The way I am creating the dialog is

m_tgtInfo = new CTargetInfo(this);
if(!m_tgtInfo) return CDialog::OnCommand(wp, lp);
m_tgtInfo->Create(IDD_DLGTGTINFO, (CWnd*)this);
m_tgtInfo->ShowWindow(SW_SHOW);

Why not create a modal dialog instead:

CTargetInfo dlg;
dlg.DoModal();

"Let us be thankful for the fools. But for them the rest of us could not succeed." - Mark Twain

"There is no death, only a change of worlds." - Native American Proverb

Re: OnInitialUpdate() never gets entered

ns30-Mar-06 10:05

30-Mar-06 10:05

Thanks, David.
It needs to be modeless. Now that I made it OnINitDialog, it does go into the function but sidesteps my if safeHWnd block for the list control on that dialog:

if(NULL != m_listTgtInfo.GetSafeHwnd())
{
    (void)m_listTgtInfo.SetExtendedStyle( LVS_EX_FULLROWSELECT );
    m_listTgtInfo.InsertColumn(0,"Keywords",LVCFMT_LEFT,800);
    //m_keysListBox.SetColumnWidth(0, LVSCW_AUTOSIZE_USEHEADER);

    m_listTgtInfo.SetExtendedStyle(LVS_EX_CHECKBOXES);
    m_listTgtInfo.InsertColumn(1,"Options",LVCFMT_LEFT,800);
}

I thought my CListCtrl would have been made by the time the code gets to the OnINitDialog. So if I cant set the columns of the listbox in this function, where else can I set them?
thanks,
sb

Re: OnInitialUpdate() never gets entered

David Crow30-Mar-06 10:31

David Crow

30-Mar-06 10:31

ns wrote:
I thought my CListCtrl would have been made by the time the code gets to the OnINitDialog.

The controls have been created, assuming you have bothered to call CDialog::OnInitDialog() first.

"Let us be thankful for the fools. But for them the rest of us could not succeed." - Mark Twain

"There is no death, only a change of worlds." - Native American Proverb

Re: OnInitialUpdate() never gets entered

ns30-Mar-06 10:40

30-Mar-06 10:40

I hadn't bothered to call OnInitDialog first.

I did MFC a long time ago then have been with QT for ages, so I am remembering only bits and pieces. I'l try to look around a little more before I post. I've forgotten where the best places are to go look for information.

Thanks again David,
hopefully I ask better questions in the next few days Smile | :)

Serial port access

LCI30-Mar-06 8:53

LCI

30-Mar-06 8:53

I would like to have access to all the pins on a serial port.
If i can get a handle to a COM port using CreateFile, does the interface allow me individual control over the 9 pins? So in other words the 9 signals some of which are DSR, RTS and DTR, can i toggle those through some class?

Thanks,

Re: Serial port access

Roger Stoltz30-Mar-06 10:15

Roger Stoltz

30-Mar-06 10:15

LCI wrote:
I would like to have access to all the pins on a serial port

This is not possible given that you don't have a driver that supports it.
The standard windows driver for serial devices does not support it.

What do you really mean by "access to all pins"? Do you really need access to all of them, or is it just a few?
Some of the pins are possible to control such as DTR and RTS by the use of ::SetCommState() and the DCB struct.
Do you intend to send serial data at all or do you wish to use the serial port in a way that it's not primarily designed for?

--
Roger

It's supposed to be hard, otherwise anybody could do it!

Re: Serial port access

LCI30-Mar-06 10:35

LCI

30-Mar-06 10:35

I just need to be able to control the RTS, DSR and DTR bits

Re: Serial port access

Roger Stoltz30-Mar-06 11:26

Roger Stoltz

30-Mar-06 11:26

The RTS and DTR signals can be controlled manually by using ::SetCommState()[^]and DCB struct[^].

The DSR signal is an hardware monitored input signal that is used for flow control and if found inactive, the data transmission will be suspended. Hence you can neither monitor nor change its state, only inform the hardware that it should be used for flow control or not.

Hope this helps
--
Roger

It's supposed to be hard, otherwise anybody could do it!

Re: Serial port access

LCI30-Mar-06 11:53

LCI

30-Mar-06 11:53

Great thanks... i just have one question on the flow here.

I can use CreateFile to obtain a handle to the port.
Then i can call SetCommState with the handle.. however, the other parameter is a DCB pointer which i will popluate the DSR, RTS and DTR settings how i need to..

Is there anything else i would need to do...
See i am trying to listen on the DSR for a signal to trigger off of that signal,
Then i would like to send signals on RTS and DTR

Re: Serial port access

Roger Stoltz30-Mar-06 20:34

Roger Stoltz

30-Mar-06 20:34

LCI wrote:
i am trying to listen on the DSR for a signal

I suggest you set up the DCB struct for the port to make use of the DSR signal, i.e. the port suspends data transfer until the DSR line assumes active state.
Use ::WaitCommEvent() to wait for a change on the DSR line and call ::ClearCommError() to verify the state of the DSR line.
Afterwards you can use ::SetCommState() to manipulate the RTS and DTR lines.

Hope this helps
--
Roger

It's supposed to be hard, otherwise anybody could do it!

Re: Serial port access

Trollslayer30-Mar-06 12:09

Trollslayer

30-Mar-06 12:09

Try P J Naughter's serial class[^], this allows access to the handshake pins.

Elaine Rose | [Rose]

The tigress is here Big Grin | :-D

how does a CDialog derived window notify the parent it was closed?

ns30-Mar-06 8:50

30-Mar-06 8:50

I launch a cDialog class window from my other CDilaog class.When it is closed by the user I want the parent to set its pointer to zero. How do I do this?

Also do I need to delete the pointer since I am creating with a'new' in the parent?
thanks,
sb

Re: how does a CDialog derived window notify the parent it was closed?

Rage30-Mar-06 9:07

Rage

30-Mar-06 9:07

ns wrote:
How do I do this?

You do it in the OnDestroy() function overriding WM_DESTROY from the CDialog class, setting the pointer to 0 with

GetParent()->m_pOnDialog = NULL;

ns wrote:
Also do I need to delete the pointer since I am creating with a'new' in the parent?

You can do a

delete this;

directly in the OnDestroy() function of the CDialog (which will kill itself, no need to hankde it in the parent window).

~RaGE();

Re: how does a CDialog derived window notify the parent it was closed?

David Crow30-Mar-06 9:33

David Crow

30-Mar-06 9:33

ns wrote:
I launch a cDialog...

Is it a modal or modeless dialog?

"Let us be thankful for the fools. But for them the rest of us could not succeed." - Mark Twain

"There is no death, only a change of worlds." - Native American Proverb

Re: how does a CDialog derived window notify the parent it was closed?

ns30-Mar-06 9:39

30-Mar-06 9:39

modeless

Re: how does a CDialog derived window notify the parent it was closed?

David Crow30-Mar-06 9:39

David Crow

30-Mar-06 9:39

Ok, so then why are you wanting/needing to assign NULL to the dialog pointer?

"Let us be thankful for the fools. But for them the rest of us could not succeed." - Mark Twain

"There is no death, only a change of worlds." - Native American Proverb

Re: how does a CDialog derived window notify the parent it was closed?

ns30-Mar-06 10:12

30-Mar-06 10:12

I have code like

               if(!m_tgtInfo)
{
    m_tgtInfo = new CTargetInfo(this);
    if(!m_tgtInfo) return CDialog::OnCommand(wp, lp);
    m_tgtInfo->Create(IDD_DLGTGTINFO, (CWnd*)this);
    m_tgtInfo->ShowWindow(SW_SHOW);
}

so if someone does away with the m_tgtInfo window then the next time I enter this function, I want to pop up a new CTargetInfo window. If m_tgtInfo is not set to null by somebody I'll never enter the block to create a new window.
Hope this makes sense.
APpreciate your input!
sb

Re: how does a CDialog derived window notify the parent it was closed?

David Crow30-Mar-06 10:27

David Crow

30-Mar-06 10:27

In the modeless dialog's PostNcDestroy() method, right before deleting the this pointer, send the parent a UDM indicating that the dialog is just about to be destroyed. In the parent's handler for the UDM, assign NULL to m_tgtInfo.

"Let us be thankful for the fools. But for them the rest of us could not succeed." - Mark Twain

"There is no death, only a change of worlds." - Native American Proverb

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