C / C++ / MFC Discussion Boards

l a u r e n7-Jan-03 18:00

7-Jan-03 18:00

ummmmm have u tried trapping the pretranslatemsg() for the dialog and filtering there too to stop the default listbox behaviour?
just a thought

"traffic lights are for people who can't make their own decisions"
biz stuff about me

CDataGrid

Gilfrog7-Jan-03 12:11

Gilfrog

7-Jan-03 12:11

Is there any way not to save the data at once. I would like to have a Ok and a Cancel button and not save the data till they hit ok.

Is there a way of doing this with a CDataGrid in VC++ 6.0.

thanks
Scott

WM_TIMER and SetTimer

Sunnygirl7-Jan-03 12:02

Sunnygirl

7-Jan-03 12:02

can i use WM_TIMER and SetTimer without a Thread?
how must i use it?
can somebody give me an example?

thanks
sunny

Re: WM_TIMER and SetTimer

Mike Nordell7-Jan-03 15:49

Mike Nordell

7-Jan-03 15:49

Sunnygirl wrote:
can i use WM_TIMER and SetTimer without a Thread?

No. On the other hand, without a thread you don't have any code running, so that shouldn't be a problem.

Perhaps your question is if you can use SetTimer and handle WM_TIMER messages in the main thread? In that case the answer is an obvious Yes. For examples, please look it up yourself. MSDN, Google, even CodeProject itself contains lots of example code.

Arrays of control

TV7-Jan-03 10:21

7-Jan-03 10:21

Hello,

I'am doing a mfc dialog based program. In this one, I have a settings dialog box that should allow the user to select somethings through check boxes. The problem is that I've a lot of checkbox in this dialog (18 check box even more later!).

I wanted to do array of controls in my settings dialog box (just like in VB). In order to do that I've short-circuited Class wizard to create an array of CButton member variables but I still have to enumerate each variable for each ID of each control with the DDX_Control(...) macro.

There is also another problem.
If the member variable is defined like this:

CButton m_variable1;

I can use the following statement:

m_variable1.SetCheck();

But if I use the following declaration:

CButton m_variable[18];
m_variable[0].SetCheck();

I'have a assertion failed.

Can somebody give me a smart way to do such array of control?

Thanks a lot.

T. Varidel

Re: Arrays of control

Alvaro Mendez7-Jan-03 11:50

Alvaro Mendez

7-Jan-03 11:50

The smart alternative: A list box of checkboxes, via the CCheckListBox class.

Regards,
Alvaro

Well done is better than well said. -- Benjamin Franklin
(I actually prefer medium-well.)

Re: Arrays of control

Heywood7-Jan-03 12:50

Heywood

7-Jan-03 12:50

You can do something like this:

CButton* pButton[] =
{
&m_chk1,
&m_chk2,
&m_chk3,
&m_chk4,
};

pButton[n]->DoSomething();

or

UINT array[] =
{
IDC_CONTROL1,
IDC_CONTROL2,
IDC_CONTROL3,
IDC_CONTROL4,
};

GetDlgItem(array[n)->DoSomething();

or use collection classes or STL;

header file:

vector<cwnd*> m_wnds;

then add your controls

int OInitDialog:

m_wnds.push_back(&m_chk1);
m_wnds.push_back(&m_chk2;
m_wnds.push_back(&m_chk3);
m_wnds.push_back(&m_chk4);

m_wnds.at(i)->DoSomething();

Re: Arrays of control

Andreas Saurwein8-Jan-03 0:38

Andreas Saurwein

8-Jan-03 0:38

Redesign your app. 18 checkboxes in one dialog is just too much.
And use a listview, a tree with checkboxes, whatever.

I don't think this is a serious possesion, and the evil most likely comes from your hand. Colin J Davies, The Lounge

system, _wsystem calls within MSVC++ dialog applications

rghin7-Jan-03 8:49

rghin

7-Jan-03 8:49

I've created a dialog application in MSVC++ on an NT platform. Within the application I'm making periodic system calls to invoke the execution of a bat file. Every time the system call is made a MS Dos Command prompt window displaying cmd.exe in the title bar appears then disappears(quite annoying). Is there a way of disabling this behavior, or is there another call that can be made to invoke the bat file without the creation of the Dos window.

Re: system, _wsystem calls within MSVC++ dialog applications

AlexO7-Jan-03 9:15

AlexO

7-Jan-03 9:15

CreateProcess with CREATE_NO_WINDOW flag

Re: system, _wsystem calls within MSVC++ dialog applications

valikac7-Jan-03 9:25

valikac

7-Jan-03 9:25

One solution is SW_HIDE and CreateProcess().

STARTUPINFO si;
si.wShowWindow = SW_HIDE;

::CreateProcess(...);

Kuphryn

Re: system, _wsystem calls within MSVC++ dialog applications

Alvaro Mendez7-Jan-03 9:25

Alvaro Mendez

7-Jan-03 9:25

CreateProcess is the official way, but if you just need a quick alternative,

WinExec("whatever.exe", SW_HIDE);

Regards,
Alvaro

Well done is better than well said. -- Benjamin Franklin
(I actually prefer medium-well.)

Windows Hooks

Nnamdi Onyeyiri7-Jan-03 8:07

Nnamdi Onyeyiri

7-Jan-03 8:07

i have made a little wrapper [in C#] for using windows hooks. When i came to test it, I found that it works on local hooks, butnot system wide hooks. i set the threadID to 0 as msdn instructs, but it doesnt work, so I was wondering if there are any special permissions needed to do such a thing. [i am using Windows Xp Pro]

1001111111011101111100111100101011110011110100101110010011010010
Sonork | 100.21142 | TheEclypse

Re: Windows Hooks

Nish Nishant7-Jan-03 10:05

Nish Nishant

7-Jan-03 10:05

Global hooks need to be in a DLL.

Nish

Author of the romantic comedy

Summer Love and Some more Cricket [New Win]

Review by Shog⁹
Click here for review[NW]

Re: Windows Hooks

Nnamdi Onyeyiri7-Jan-03 10:34

Nnamdi Onyeyiri

7-Jan-03 10:34

Nishant S wrote:
Global hooks need to be in a DLL.

Well thats a bit stupid if you ask me. is that the SetWindowsHookEx call - or the callback in the dll?

1001111111011101111100111100101011110011110100101110010011010010
Sonork | 100.21142 | TheEclypse

Re: Windows Hooks

Nish Nishant7-Jan-03 11:31

Nish Nishant

7-Jan-03 11:31

Nnamdi Onyeyiri wrote:
Well thats a bit stupid if you ask me

That's the only way to load it into the address space of other executables.

Nnamdi Onyeyiri wrote:
or the callback in the dll?

That's the one

Nish

Author of the romantic comedy

Summer Love and Some more Cricket [New Win]

Review by Shog⁹
Click here for review[NW]

CRichEdit crashes

Ricky_TheBard7-Jan-03 8:06

Ricky_TheBard

7-Jan-03 8:06

Hy everyone!
I have a problem here...
my CRichEditCtrl, when it haves more than ~250 characteres, it crashes, and loses my CHARFORMAT atributes.
Or, if I try to make CString::GetLength() with the String that is associate with the control, it crashes too...
does anyone have some idea?

thanks!

Ricky

Detecting when an internet connection is active

fferland7-Jan-03 7:52

fferland

7-Jan-03 7:52

I need to know how I can detect whether the user currently has an active internet connection. Can anyone help? I've tried InetIsOffline(), but that only determines if the user is in online or offline mode, not if the actual connection is currently active.

Re: Detecting when an internet connection is active

valikac7-Jan-03 9:20

valikac

7-Jan-03 9:20

One solution is to simply connect to a server.

Kuphryn

Re: Detecting when an internet connection is active

Todd Smith7-Jan-03 9:58

Todd Smith

7-Jan-03 9:58

bool IsConnectedToInternet(void)
{
	DEBUGF("IsConnectedToInternet");

	WORD wVersionRequested = MAKEWORD(1, 1);
	WSADATA	wsaData;
	TCHAR hostaname[1000];
	int	hostname_size = sizeof(hostaname);
	bool connected = false;

	if (WSAStartup(wVersionRequested, &wsaData) != 0)
	{
		DEBUGF("WSAStartup Failed (%i.%i) %s",
			wsaData.wHighVersion, wsaData.wVersion, wsaData.szDescription);
		return connected;
	}

	if (gethostname(hostaname, hostname_size) != SOCKET_ERROR)
	{
		struct hostent FAR *h = gethostbyname(hostaname);
		if (h != NULL)
		{
			// cif ip=127.0.0.1 then we are not connected
			DEBUGF("gethostname %s %s", h->h_name, h->h_addr_list[0]);
			if (strncmp(h->h_addr_list[0], "\x7f\x0\x0\0x1", 4)!=0)
			{
				connected = true;
			}
		}
	}
	else
	{
		DEBUGF("gethostname Failed");
	}

	WSACleanup();

	return connected;
}

Todd Smith

CStatic scroll bar

Dean Goodman7-Jan-03 7:37

Dean Goodman

7-Jan-03 7:37

Is it possible to add a scroll bar to a CStatic control?

I've derived a new base class from CStatic for graph/chart purposes, and I'd like to be able to allow the graph to scroll if it is too big for the available viewing area. I've found many graphing projects on the net, but none seem to have this feature which is of particular importance to me since I have long series of data.

I've tried adding the WS_HSCROLL and WS_VSCROLL styles, I've called EnableScrollBarCtrl(), and I've called ShowScrollBar() but none of these methods have any effect. Anyone know something I don't?

A second question: I've also added the SS_NOTIFY style, but my (base) class isn't receiving the notification. Do I have to override the message notification in every other class I derive from the base class to process the notification?

Thanks for the help,

--Dean

Re: CStatic scroll bar

PJ Arends7-Jan-03 11:48

PJ Arends

7-Jan-03 11:48

FWIW, I would have derived the control from CWnd, not CStatic. CStatic has too many restrictions such as the ones you described.

CPUA 0x5041

Sonork 100.11743 Chicken Little

"So it can now be written in stone as a testament to humanities achievments "PJ did Pi at CP"." Colin Davies

Within you lies the power for good - Use it!

ListView InsertMark does not display

Hiusing7-Jan-03 6:59

Hiusing

7-Jan-03 6:59

Hello,

I have a listview that has LVS_ICON | LVS_ALIGNTOP | LVS_AUTOARRANGE style. I use ListView_InsertMarkHitTest do the hittest and ListView_SetInsertMark for the insert mark during drag-n-drop (DragOver). However, the insertion mark never display.

Do you have any idea?

Thanks,
Hiusing

Context Help on a button in MFC CFormView

DionChen7-Jan-03 5:55

DionChen

7-Jan-03 5:55

Hi, all:

I am using VC6.0. I have a SDI application with Help system. All the toolbar buttons, menu items can get the context help, supported by the framework. I have three buttons on my CFormView window, I'd like to get context help on those three buttons when I use Context Help ( Arrow+question mark). What should I do to enable help on those three buttons?

I noticed that I have file called Resource.hm and it contains HIDC_MYBUTTON1,2,3. It is included in MyApplication.rc file. But I don't know how to get the context help on those.

Any help is highly appreciated.

Dion

Dion

Re: Context Help on a button in MFC CFormView

PJ Arends7-Jan-03 11:54

PJ Arends

7-Jan-03 11:54

http://www.codeproject.com/dialog/dlgboxtricks.asp[^]

A little over half way down the page. The method described works with dialogs, and should also work with form views.

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.