type cast problem when going from VS6->VS.NET - C / C++ / MFC Discussion Boards

summo9-Apr-03 2:15

9-Apr-03 2:15

In the code below packet_handler function is not the member of the
class I want to display the data generating from this function to be displayed on the list box. But handle to the list box is not there as is not the member of the class.
Is there any way I can get handle of listbox into the function p_h
below.
It is important the funtion declaration of "paket_handler" is defined in the library file so the return type or parameter cannot change.

//defined in winpcap library

void sniff::OnButton1() {
pcap_loop(adhandle, 0, packet_handler, NULL);//call to the call back //packet_handler function
}

void packet_handler(u_char *param, const struct pcap_pkthdr *header, const u_char *pkt_data)
{
ih = (ip_header *) (pkt_data + 14); //length of ethernet header

ip_len = (ih->ver_ihl & 0xf) * 4;
......//more code
......
/* print ip addresses and udp ports */
printf("%d.%d.%d.%d -> %d.%d.%d.%d\n",
ih->saddr.byte1,ih->saddr.byte2,ih->saddr.byte3,ih->saddr.byte4,

ih->daddr.byte1,ih->daddr.byte2,ih->daddr.byte3,ih->daddr.byte4);

}

Reply me soon

CreateThread / ExitThread

Paul Farry9-Apr-03 2:03

Paul Farry

9-Apr-03 2:03

I've got some threads I've created ... mm nice Wink | ;-)

In the thread function should I ExitThread or should I just return?
If I ExitThread, what should I specify for the value if everything is fine?

hThread = CreateThread(
NULL, // no security attributes
0, // 0 = use default stack size
CopyFileFunction, // thread function
this, // argument to thread function
0, // use default creation flags
&dwThreadId); // returns the thread identifier

//
//.............
//

DWORD WINAPI CopyFileFunction(LPVOID lpParam)
{
ExitThread(1);

return 0;

)

Re: CreateThread / ExitThread

Zdeslav Vojkovic9-Apr-03 2:35

Zdeslav Vojkovic

9-Apr-03 2:35

you don't have to call ExitThread() explicitly, but if you use C-runtime functions inside the thread function, you should use _beginthreadex() instead of CreateThread() (otherwise some stack data for certain methods won't be initialized and you might have memory leaks)

Transfer of a SDI application to MDI

Claude Gagnon9-Apr-03 1:38

Claude Gagnon

9-Apr-03 1:38

Hi,

I utilize Visual C++ 6.0.

I have develop an application with menus and dialogs in SDI.

I want to transfert it to a MDI application.

There is a way to keep my dialogs and menus and transfer it to the MDI
project ?

Thanks,

Claude

Dao problem

naradaji9-Apr-03 1:27

naradaji

9-Apr-03 1:27

Hi all,

I'm creating a small application that uses DAO (I know, it's old-fashioned!).
I need to store in a field a text with more than 255 characters. So far I have used:

dbTable.CreateField("Error",dbText,255);

with success, but with the 255 limitation. I tried:

dbTable.CreateField("Error",dbMemo,2048);

but it's still 255-limited.

How can I create a field for a long text?

I'd appreciate any ideas.

Thanks a lot.

-- narada

Confused | :confused:

Re: Dao problem

G. Steudtel9-Apr-03 23:43

G. Steudtel

9-Apr-03 23:43

Hi,
first of all memo fields do have an initial length of zero.
Then check your UpdateData function, if there is a length restriction.
This can be done by explicitly setting the text length of the control or by DDV_MaxChar(....).

G. Steudtel

Re: Dao problem

naradaji9-Apr-03 23:58

naradaji

9-Apr-03 23:58

So you don't think this is an Access restriction?

type cast problem when going from VS6->VS.NET

Mathias S.9-Apr-03 0:43

Mathias S.

9-Apr-03 0:43

Visual Studio.NET refuse to compile this. get type cast error
in VS 6 it works.

CGridItem* CMyGridCtrl::GetNextItem( DWORD h )<br />
{<br />
	std::vector<CGridItem*>::iterator it;<br />
<br />
	// ERROR C2440<br />
	it = ( std::vector<CGridItem*>::iterator )h;<br />
	// Also tried <br />
	// it = static_cast< std::vector<CGridItem*>::iterator >( h);<br />
<br />
	it++;<br />
	if( isItemValid( it ) )<br />
		return (*it);<br />
	return NULL;<br />
}

Re: type cast problem when going from VS6->VS.NET

jhwurmbach9-Apr-03 1:13

jhwurmbach

9-Apr-03 1:13

Try
it = reinterpret_cast< std::vector::iterator >( h)
as the two types are totally unrelated.

[edit]Or did you try
it = static_cast< std::vector< whatever >::iterator >( h)
with whatever being the type of your vectors datatype.
[/edit]

My opinions may have changed, but not the fact that I am right.

Re: type cast problem when going from VS6->VS.NET

Mathias S.9-Apr-03 1:26

Mathias S.

9-Apr-03 1:26

reinterpret_cast didn't work..

The interator is casted to DWORD becouse some of the classes are also used in other projects and types is not known there.
Properly some bad design somewhere. But I don't want and have the time to rewrite tons of code.

This is just one of many type cast problem. But it looks like most of the problem are handles/DWORDs getting casted to interators.

Re: type cast problem when going from VS6->VS.NET

Mathias S.9-Apr-03 1:29

Mathias S.

9-Apr-03 1:29

yes
Cut and Paste Error..
it should say
it = static_cast< std::vector< CGridItem* >::iterator >( h)

nothing works. strange..

Re: type cast problem when going from VS6->VS.NET : Solved . maybe

Mathias S.9-Apr-03 1:53

Mathias S.

9-Apr-03 1:53

Problem has been solved. I think..

On VS6 I'm using SGi STL instead of the one included by MS in VS6..
But in VS.NET I was using the provided.

But when I changed so SGI STL is used in VS.NET those compile error went away
But I get some strange warnings instead on other stuff. But I think I can ignore them. Looks like the program is working now.

Blinking Object

SatyaDY9-Apr-03 0:31

SatyaDY

9-Apr-03 0:31

Hi,
In one of my project, I am plotting the line for some trajectory, in addition to this I want to show a blinking object at the beginning of the trajectory. I tried creating a bitmap (8 x 8) and tried to put it on the screen with BitBlt function in VC, but it's disturbing the line plotted. It should not distrub the plotted things, How to do it?? Can anybody give some idea or some code??
Regards
Satya

Re: Blinking Object

Roger Allen9-Apr-03 3:05

Roger Allen

9-Apr-03 3:05

Could you use an OS caret to do this? Use CreateCaret() and set the height/width of it and position at the start of your tradjectory.

May so what you need and then the OS can handle all the drawing stuff for you.

Roger Allen
Sonork 100.10016

Were you different as a kid? Did you ever say "Ooohhh, shiny red" even once? - Paul Watson 11-February-2003

Asynchronously inserting large number of items into TreeView

henchook8-Apr-03 23:44

henchook

8-Apr-03 23:44

I need to insert a very large number of items into a CTreeView derived control. This insertion takes a long time, so I am doing is asynchronously.

My problem is: whenever I call InsertItem, the tree selection jumps to the newly inserted item. I want to prevent this, so that my user sees the tree being built, but is able to select an item in the tree and have the selection remain on that item.

How would I go about doing this? I tried looking for and using different window styles, and I tried intercepting the TVN_SELCHANGED and TVN_SELCHANGING messages, but wasn't quite able to achieve anything...

I want it to behave sort of like IE does when you open a huge (and I mean HUGE, as in 1MB) XML file.... IE parses the file in the background, and keeps adding new nodes to it, but you are able to view whichever part of the document (that has already been loaded you want).

Thanks,
-CD

Re: Asynchronously inserting large number of items into TreeView

valikac9-Apr-03 11:35

valikac

9-Apr-03 11:35

One solution is to keep a reference of the current selected item. Upon inserting new items, call TreeView_Select().

Kuphryn

Re: Asynchronously inserting large number of items into TreeView

henchook9-Apr-03 20:29

henchook

9-Apr-03 20:29

The problem was that after inserting each item, there was a call to Expand(), which caused the treeview to scroll to the newly expanded icon. This did not have any visible effect when the tree was being populated off-screen, but once I started doing this in a separate thread after showing the treeview, it was apparent in the tree jumping all over the place.

It turns out (this is code I inherited from someone else at my company) that the proper thing to do, instead of calling Expand() after inserting each item, is to set the State bits (and the mask bits) in the TVINSERTSTRUCT before inserting the item, this causes it to be expanded when it is inserted, without the tree scrolling to it.

Thanks anyway for your help.

Howto set the dropped height of a combobox?

Brian van der Beek8-Apr-03 23:38

Brian van der Beek

8-Apr-03 23:38

How do you set the dropped height of a CComboBox that is created dynamically? Confused | :confused:

Re: Howto set the dropped height of a combobox?

Roger Allen9-Apr-03 3:02

Roger Allen

9-Apr-03 3:02

MoveWindow() is what you need. Move the window to the area the combo needs and the drop area. The combo will only use the top part when the drop area is not shown. When the drop area is shown, this will expand down to the window coordinates specified in the MoveWindow() call.

Roger Allen
Sonork 100.10016

Were you different as a kid? Did you ever say "Ooohhh, shiny red" even once? - Paul Watson 11-February-2003

Maintaining code on both VC6 and VC.NET

Aza8-Apr-03 23:33

Aza

8-Apr-03 23:33

Hi,

Because of dependencies to external software (and their SDKs) that uses MFC4.2 in old versions of their software and MFC7.0 in newer version I have to compile two versions of my software, one under MFC4.2 and one version under MFC7.0.

Is there any way that I can accomplish this without maintaining separate dsw and sln files?
Is there any way of setting up my project to use another compiler/linker?

Thankful for any help,

Johannes

MFC.

frackasse8-Apr-03 23:01

frackasse

8-Apr-03 23:01

HI,

I have a problem concerning MFC with visual C++ 6.0

I want to insert item in a Tree. This Item will be selected via a menu which will open a window for the item selection. that is for the context!

I have problem of classes and i don't understang very well which classes must I choose for my differents window. Could you help me ?

For the tree which is in a the main window i choose a form view
and for the others windows ( for item selections) i create my own class.
But it doesn't work.

Sorry for mistakes,
i am french Wink | ;)

USB Bluetooth communication

gcaboi8-Apr-03 22:41

gcaboi

8-Apr-03 22:41

Hi!

I have to write an application, which should communicate over a Bluetooth dongle for USB. Since I never wrote any drivers or such hardware based applications before, I have no idea how to handle this. The MSDN only offers information for Windows CE, but this application should run under Windows 2000.
Can anyone help me???
Confused | :confused:

Multiline Tooltips?

Rob Caldecott8-Apr-03 22:33

Rob Caldecott

8-Apr-03 22:33

Before I rush off and port Chris Maunders extended tooltip article to WTL ( Smile | :)

), I wondered if there was an easier way to get multiline tooltips to display? It seems that Windows already has support for this (such as the tips displayed on quick-launch icons on the task bar) - can I not leverage this somehow?

When I am king, you will be first against the wall.

Re: Multiline Tooltips?

Rob Caldecott8-Apr-03 23:35

Rob Caldecott

8-Apr-03 23:35

Groan. I solved this by using a combination of TTM_SETMAXTIPWIDTH and "\r\n" to force new lines. I expect "\r\n" to just work, but it seems you must send a TTM_SETMAXTIPWIDTH first.

When I am king, you will be first against the wall.

Adding MFC project to Property Sheet

dandy778-Apr-03 22:27

dandy77

8-Apr-03 22:27

Hi, there.
I've got a problem with using property sheet.

Actually, I wanted to use Tab control, but it is really hard and complicated to add some controls on each tab.
so I decided to use property sheet.

I have 4 independent MFC(exe) projects.
Those are not related each other except input parameter.
With one input parameter, 4 projects make diffent kinds of results.
Each project does File I/O and uses even FileDialog.
I tried to put each project on each property page.
(using copy and paste)
However, I faced some serious problem.
Each project has OnInitDialog function, but each property page doesn't have it.
Can I just add this function on each property page?
(Actually I tried to do that, I couldn't get the results what I wanted.)
Without OnInitDialog, any project doesn't work properly.
I really want to combine 4 projects to one dialog box.

How can I solve this problem?
Do I have to use other methods to combine them?
Please help me.

Thank you!!!

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