C / C++ / MFC Discussion Boards

Shog⁹4-Jan-05 14:36

4-Jan-05 14:36

Generally, Doc/View is set up such that the document provides access to whatever data there is, and also sends notifications when that data changes. The views are responsible for deciding which data they'll display, how they'll display it, and how they respond to notifications. In your scenario, S should communicate to D the data change in such a way that D can update its buffer efficiently (potentially changing only those bytes that have actually changed, for instance), and then send a notification. The notification should reflect how the data has changed, such that the views can update themselves efficiently. Each view should then determine whether the change has any relevance to what it displays, and update appropriately.

Of course, these are guidelines - you can implement it in whatever way makes the most sense for your particular needs. There's no "one size fits all"... Smile | :)

You left me high and dry and changed me You lied to me and now i’m angry...

Re: Doc View question

act_x4-Jan-05 14:47

act_x

4-Jan-05 14:47

Thank you for your reply .

char* from C++ dll in C#

vinayakdl4-Jan-05 12:31

vinayakdl

4-Jan-05 12:31

Hi,
I am trying to return a string(char*) from a c++ dll and the string i return comes out blank. can anyone help me on this.

Vinayak D. Labade

Re: char* from C++ dll in C#

Anthony_Yio4-Jan-05 20:53

Anthony_Yio

4-Jan-05 20:53

where did you allocate your storage?

most people pass in the allocate storage with it size to the function they intended to call

char *pNew = new char[100];
memset(pNew, NULL, sizeof(pNew));
yourDLLFuncCall(pNew, sizeof(pNew));
delete [] pNew;

so that they could deallocate it once done at the caller itself. If you allocate storage in your DLL function and deallocate it in your main exe, there would be a tendency of getting a memory leak or crash when calling delete.

Sonork 100.41263:Anthony_Yio

Maximizing view

act_x4-Jan-05 10:55

act_x

4-Jan-05 10:55

On startup how do i resize the view to fit the size of the parent frame ?

Re: Maximizing view

KaЯl4-Jan-05 21:39

KaЯl

4-Jan-05 21:39

I would try to maximise the Child Frame holding the view, like this for example (supposing you use MFC):

<code>
void CChildFrame::ActivateFrame(int nCmdShow) 
{
   // Create the child frame window maximized
   nCmdShow = SW_MAXIMIZE;
   
   CMDIChildWnd::ActivateFrame(nCmdShow);
}

HTH,

Fold With Us!
"For every complex problem there is an answer that is clear, simple, and wrong" - H.L. Mencken

Re: Maximizing view

Rahim Rattani4-Jan-05 21:57

Rahim Rattani

4-Jan-05 21:57

Please be more precise and explain your problem clearly for better and beneficial replies.

Rahim Rattani
Software Engineer,
Matrix Systems (Pvt) Ltd.,
Karachi - Pakistan

IP address resolution

Themis4-Jan-05 10:16

Themis

4-Jan-05 10:16

Hello, I 'm writting an application with winsock and I want to resolve an ip address from a hostname. What I need is a function call to whom I 'll give for example "www.codeproject.com" and it will return to me its ip address. I know that there's such a function but I can't find it.

Thanks in advance,
Themis

Re: IP address resolution

Roger Wright4-Jan-05 10:47

Roger Wright

4-Jan-05 10:47

There are a couple of nice examples here[^].

"If it's Snowbird season, why can't we shoot them?" - Overheard in a bar in Bullhead City

Sending strings (or characters) through sockets.

SimCom4-Jan-05 10:15

SimCom

4-Jan-05 10:15

Hello my best friends,

I'm a beginner to Visual C++ programming, so I have some "stupid" questions for you and I hope you guys to help me.

I'm working on my own very simple chatapplication, but I encounterd some problems. I've made a client and a server part, I've tested it out but I had the problem that I couldn't send a text string. My serverside establishes a connection with the clientside ( I know it because I put some control messages to be sure there is a connection).

But when I try to send a peace of text, it does nothing except that it shows the sending text on my display and the receiver part shows nothing on the display. I used the following code to send a string:

void CSimComDlg::OnSend()
{
m_Message.GetWindowText(strMESSAGE);
m_pArOut->WriteString(strMESSAGE);
m_pArOut->Flush();
m_MsgDsp.SetWindowText(_T(Name+":"+strMESSAGE+"\r\n"));
strMESSAGE.Empty();
}

And to read a received string:

void CSimComDlg::ReadReceive()
{
m_pArIn->ReadString(strMESSAGE);
m_MsgDsp.SetWindowText(_T("Chatter:"+strMESSAGE+"\r\n"));
strMESSAGE.Empty();
}

m_pArOut and m_pArIn are CArchive pointers (I use this in combination with CSocketFile to send data over internet).

Is there something wrong with these codes? D'Oh! | :doh:

I've seen some other example codes on the internet, they include also the length of the message to send and they check also the buffer if there's more data coming in. But are they neccesary to put them in my code?

I hope you can help me boyzz Blush | :O

If my application works, I forget all my problems.

Microsoft Word Event handling help...

Moozz4-Jan-05 10:09

Moozz

4-Jan-05 10:09

I am trying to capture events from a running instance of Microsoft Word. If I could do this using MFC libraries, this would be a walk in the park. However, I HAVE to do this using straight C++ without the help of MFC libraries what-so-ever.

I have done a lot of reading (especially on this site) on this topic and have tried to implement this event handling in a VC++ console application. I understand that you need to have event sinks to handle these events and that the COM object has to support the interface that the client application is exposing. The problem I have, is that in all the examples I have found on the web, the developers have created their own COM object and have a client that talks to that. What I haven't been able to find, is a straight forward example of how to make a connection to any of the Microsoft Office applications using the Adise method. Every time I try it, it fails.

Could anyone help me? I just need a basic explanation of how to set up this connection, or better yet, some very basic source on how to do this.

Any help would be massively appreciated!

Struct array with string identifier

Oscar Rodriguez4-Jan-05 9:55

Oscar Rodriguez

4-Jan-05 9:55

I need to know if someone can tell me how i can make an struct array what uses an LPSTR or anything similar identifiyng method instead of the normal int method , i need it for a project in that i am.

Thank you for your help

Example:

MyArrayStruct("identifier").Anything=0xFF;

Re: Struct array with string identifier

C^hris L^osinger4-Jan-05 10:14

C^hris L^osinger

4-Jan-05 10:14

you need a map. try a CMap or a std::map

CMap< CString, LPCSTR, CPerson, CPerson& > myMap2;
CPerson person;
LPCSTR lpstrName = "Jones";
myMap2->SetAt( lpstrName, person );

   typedef map< CString , CPerson> clrMap;

theMap clrMap;
...

	clrMap::const_iterator it;
	it = theMap.find(name);

	// did we get one?
	if (it!=theMap.end())
	{
		return (*it).second;
	}

Software | Cleek

Re: Struct array with string identifier

Oscar Rodriguez5-Jan-05 0:23

Oscar Rodriguez

5-Jan-05 0:23

Thank you Chris Losinger , I only make you one question, the first mode uses MFC if i`m not wrong, but the second don't uses it, right?

PD: I don't use that in my project, i need do it withuot the MFC classes, only with C++...

Re: Struct array with string identifier

C^hris L^osinger5-Jan-05 1:09

C^hris L^osinger

5-Jan-05 1:09

correct. if you don't use MFC, std::map will still work for you.

i would recommend std::map over CMap in any case.

-c

Software | Cleek

Re: Struct array with string identifier

Oscar Rodriguez6-Jan-05 1:26

Oscar Rodriguez

6-Jan-05 1:26

another question how i implement this function??
do you can explain me???

please...

Thank you

Re: Struct array with string identifier

C^hris L^osinger6-Jan-05 2:10

C^hris L^osinger

6-Jan-05 2:10

there are many tutorials for std::map on the web. here is one: http://pegasus.rutgers.edu/~elflord/cpp/stdlib/map.html[^]

-c

Software | Cleek

Linking C libraries to C++?

balaclavabob4-Jan-05 8:48

balaclavabob

4-Jan-05 8:48

Pre-compiled a C library using msvc 6, blah.lib

In a new C++ project, include header and library location in Tools->Options->Directories, included header in the C++ file and include library in the Settings->Link tab

I get a linker error stating:

main.obj : error LNK2001: unresolved external symbol "int __cdecl hInitialise(int,struct HWND__ *,struct HDC__ *,unsigned int)" (?hInitialise@@YAHHPAUHWND__@@PAUHDC__@@I@Z)

I was not able to recompile the library into C++, cause of header problems....

Re: Linking C libraries to C++?

Chris Meech4-Jan-05 9:15

Chris Meech

4-Jan-05 9:15

This smells like a name mangling issue. Try to wrap the header file that contains your function declarations with

extern "C"
{
...
...   all of your functions
...
}

and then rebuild your library and then rebuild your app.

Chris Meech

I am Canadian. [heard in a local bar]

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Nice sig! [Tim Deveaux on Matt Newman's sig with a quote from me]

Re: Linking C libraries to C++?

balaclavabob4-Jan-05 10:40

balaclavabob

4-Jan-05 10:40

Thanks for the suggestion Chris, it didn't work.
The cpp files generated a host of other errors.

I googled extern "C" to see how else I could use it.

I tried putting the function declaration at the top of my file and used:
extern "C" int hInitialise(int count,
HWND window,
HDC screen,
unsigned int flags);
Got a compile error:
main.cpp(13) : error C2732: linkage specification contradicts earlier specification for 'hInitialise'
But I copied it straight from the header.... Confused | :confused:

Re: Linking C libraries to C++?

Michael Dunn4-Jan-05 10:50

Michael Dunn

4-Jan-05 10:50

You don't have to copy anything. In your C++ code do this:

extern "C"
{
#include "your_c_header.h"
}

--Mike--
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Obtaining a handle to a textbox and populating it with text

willertron4-Jan-05 8:43

willertron

4-Jan-05 8:43

Hello,

I have got a handle to a window:

HWND hWndAddEditWindow = NULL;
hWndAddEditWindow = FindWindow(NULL,_T("New/Edit"));

I then open the window using the handle but I then need to populate the text boxes on the window who's names and ID's change each time.

I have been told that there is a way to get a handle to the first textbox, followed by the second textbox and so on, but I have not been able to work out how.

Please could someone help me out by telling me how I can get a handle to the first two textboxes in the window and send some text to them.

Many thanks
Willertron

www.willertron.com

Re: Obtaining a handle to a textbox and populating it with text

Blake Miller4-Jan-05 9:49

Blake Miller

4-Jan-05 9:49

The EnumChildWindows function enumerates the child windows that belong to the specified parent window by passing the handle to each child window, in turn, to an application-defined callback function. EnumChildWindows continues until the last child window is enumerated or the callback function returns FALSE.

You then could use the GetClassName function retrieves the name of the class to which the specified window belongs on each hWnd to make sure it is a text box.

Re: Obtaining a handle to a textbox and populating it with text

BlackDice4-Jan-05 11:11

BlackDice

4-Jan-05 11:11

after you get the handle to that window, use FindWindowEx() to go through the children. If you're using MFC, use mfc's CWnd version of FindWindowEx(). that way you can get a CWnd*, cast it to CEdit* and do whatever you want with it.

My articles

www.stillwaterexpress.com

BlackDice

fatal error C1010: from VC++ .net HELP!!!

bobhou4-Jan-05 8:07

bobhou

4-Jan-05 8:07

I start a new W32 console VC++ project from VC++ .net and
add a class (one .cpp and one .h files) to this project.
It gives an error when compiling:
fatal error C1010: unexpected end of file while looking for precompiled header directive

It doesn't happen in VC++ 6.0.

Could anybody pls help me on this?

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