Re: OOP Question - Passing Data Between Objects - C / C++ / MFC Discussion Boards

Ben Burnett21-Oct-01 6:07

21-Oct-01 6:07

Just a guess, but I imagine MS uses it for backwards compatibility (I don’t think there are to many of us who will need to use it). Say for exmple if MS were to constantly be changing the location of Windows specific registry keys, they could simply add links under the old keys that point to the new ones. This would make it so older software would not break under a new version of Windows (yeah right).

My 2 cents.

Ben Burnett

"It's all absolutely devastatingly true -- except the bits that are lies"
- Douglas Adams

A rounded MFC Dialog How?

MaTrIX2k220-Oct-01 15:16

MaTrIX2k2

20-Oct-01 15:16

I've found an article that shows how to make an app with non-rectangle window, but is not MFC, how can i use the MFC to make a non-rectangle Dialogs based app?

Re: A rounded MFC Dialog How?

Michael Dunn20-Oct-01 17:34

Michael Dunn

20-Oct-01 17:34

Most Win32 APIs are duplicated as CWnd member functions. If the APIs you need aren't, then just call the API and pass it your dialog's HWND - call CWnd::GetSafeHwnd() to get the HWND.

--Mike--
http://home.inreach.com/mdunn/
"....." -- Silent Bob
Heart | [heart]

your

with

and

Re: A rounded MFC Dialog How?

Michael P Butler21-Oct-01 3:22

Michael P Butler

21-Oct-01 3:22

Have a look at http://www.codeguru.com/dialog/RoundDialog.shtml

Michael Smile | :)

Macro to get class name / function name?

danwatt20-Oct-01 14:34

danwatt

20-Oct-01 14:34

I know that there are the __FILE__ and __LINE__ macros, but is there some sort of equivalent that produces the current function and class names? I know that some compilers support
__FUNCTION__ or __func__, but MSVC does not seem to support this. Is there a way to do this in MSVC??

Re: Macro to get class name / function name?

Jim Crafton20-Oct-01 17:55

Jim Crafton

20-Oct-01 17:55

maybe you already know this, but if you have RTTI info turned on and use the typeid() keyword
you can easily get the class name of an object

Base* someClass = .....

char* className = typeid( *base ).name();

your out of luck for functions, so far as I know.

OOP Question - Passing Data Between Objects

AJ12320-Oct-01 13:35

AJ123

20-Oct-01 13:35

Hi,

I have a scenario, where i have an object say 'A' which has a member varible which is another object say 'B'.

I want to be able to pass data from object B Up To A. Without B have any knowledge of A.

Anyone any sugestion, Surely this must be a regular task.

Cheer

Richard

Re: OOP Question - Passing Data Between Objects

Ben Burnett21-Oct-01 6:15

Ben Burnett

21-Oct-01 6:15

// class B ////////<br />
class B {<br />
<br />
public:<br />
int getData () { return data; }<br />
<br />
private:<br />
int data; // B's data<br />
<br />
};<br />
<br />
// class A ////////<br />
class A {<br />
<br />
public:<br />
void printBData () { <br />
<br />
    int data = myB.getData ();<br />
    cout << "B's data: " << data << nl;<br />
<br />
}<br />
<br />
private:<br />
B myB;<br />
<br />
};

Ben Burnett

"It's all absolutely devastatingly true -- except the bits that are lies"
- Douglas Adams

Re: OOP Question - Passing Data Between Objects

Andrew Peace21-Oct-01 11:05

Andrew Peace

21-Oct-01 11:05

There are two methods that you could consider;

1. Instead of having B push the information to A, why not have A query B for the information when it's needed?

2. Use a proxy class. Thus, B and A will know about C, and B will use C to pass information to A. This is similar to the observer pattern (I think?) - there's a good articleon this site about the observer pattern but I can't remember exactly where now.

--
Andrew.

Taskbar?

MaTrIX2k220-Oct-01 9:58

MaTrIX2k2

20-Oct-01 9:58

How can i make a taskbar in my app?

Re: Taskbar?

Michael P Butler20-Oct-01 11:13

Michael P Butler

20-Oct-01 11:13

Have a look at CDialogBar or have a browse here http://www.codeproject.com/docking/

Of course if you mean something else, post a bit more detail.

Michael Smile | :)

Re: Taskbar?

MaTrIX2k220-Oct-01 11:46

MaTrIX2k2

20-Oct-01 11:46

I mean a taskbar in the app 'coz when i minimize my dialogs don't keep a little window, and stay in a bar just like mIRC and other programs.

Variables under different class

Kuniva20-Oct-01 6:52

Kuniva

20-Oct-01 6:52

I have two seperate classes for two different dialogs in MFC. Now i want to acces the variables of one dialog in the code of the other class of the other dialog. How do i do this?

Thanx

Kuniva

Want, take, have.

Re: Variables under different class

Michael P Butler20-Oct-01 11:17

Michael P Butler

20-Oct-01 11:17

The easiest way is to declare the variables as public members of the class and then access them in the usual c++ way,

void CDialog1::Test()
{
    CDialog2 dlg;
     
    // set flag
    dlg.m_bTestFlag = TRUE;
    int nRet = dlg.DoModal();

    if(nRet == IDOK)
    {
       // get new state
       BOOL bTest = dlg.m_bTestFlag;
    }
}

Find a string in a file

Maer72720-Oct-01 3:02

Maer727

20-Oct-01 3:02

How to find a string in a file?
Are there any VC functions that I can use directly?

Can you help?

Thanks,
Maer

Re: Find a string in a file

NormDroid20-Oct-01 3:28

NormDroid

20-Oct-01 3:28

If your file is a text file which I assume it is, try this...

CStdioFile file;
if (!file.Open("c:\\file.txt", CFile::modeRead))
return;

CString str;
while (file.ReadString(str))
{
if (str.Find("Search String) != -1)
{
TRACE("Found it!");
}
}

Normski - Professional Windows Programmer

Re: Find a string in a file

Maer72720-Oct-01 3:58

Maer727

20-Oct-01 3:58

Hi, Normski!

Thanks for your reply! It is the one I am looking for!

Have a nice weekend!
Maer

Re: Find a string in a file

NormDroid20-Oct-01 4:02

NormDroid

20-Oct-01 4:02

and you my friend!

Normski - Professional Windows Programmer

Re: Find a string in a file

Maer72720-Oct-01 19:12

Maer727

20-Oct-01 19:12

Thanks pal!

- My weekend is not as good as yours. My girl is in another city. 200KMs away. We just chat throught the net. ^__^

Regards,
Maer

Passing Pointers To Function In C++

AJ12320-Oct-01 2:26

AJ123

20-Oct-01 2:26

Hi,

What I want, is to pass a function which is a member of one object into the contructor of a new object it declares. So the new object can then call it.

Keep getting errors along the lines of:

error C2664: '__thiscall CTest::CTest(void (__cdecl *)(char *))' : cannot convert parameter 1 from 'void (char *)' to 'void (__cdecl *)(char *)'

Can Anyone offer Any Advice, it work if i declare the function as a static.

Guess it's a c++/c isssue. The function prototype is for a standard c function where i want it to be for a class memeber function

Or is this the sort of thing that should be done through some Object Orientated Programming principle.

Thanks, Much Appreciated

Richard Jackson

Re: Passing Pointers To Function In C++

Tim Deveaux20-Oct-01 5:04

Tim Deveaux

20-Oct-01 5:04

Yes, you've pretty much got it - the non-obvious part is the passing of the implicit this pointer to member functions, which alters the function signature of those functions.

Filter on thiscall in this forum for more info. There's also a bit in the FAQ on using member fns as C (Windows) callbacks.

*** Multiple Client Socket in MFC ***

Salman Ahmad Khan20-Oct-01 0:24

Salman Ahmad Khan

20-Oct-01 0:24

Hi,
in MFC using CSocket or CAsyncSocket following approach can set communication between a client socket and a Connecting socket on server side.

ListeningSocket.Accept ( ConnectingSocket );

Confused | :confused:

Problem, How will multiple clients be implemented?

Cool | :cool:

I have the clue that Link List, Array, Threads might be used for creating multiple connections with multiple clients.
like ListenSock.Accept ( ConnectSock[i] );

Confused | :confused:

BUT how will the messages be handeled. How will one connecting socket differentiate form otherones message.

Cry | :((

PLZ HELP !!!!!

RawCoder

Re: *** Multiple Client Socket in MFC ***

NormDroid20-Oct-01 0:35

NormDroid

20-Oct-01 0:35

I would strongly recommend NOT using the MFC implementation wrappers for sockets.
The best and *orthodox* way to to use raw sockets WSAEvent etc.
A very good book to but describing the programming of sockets for windows is
"Winsock 2.0" - By Lewis Napper.

Re: *** Multiple Client Socket in MFC ***

Salman Ahmad Khan20-Oct-01 1:10

Salman Ahmad Khan

20-Oct-01 1:10

I really need to do it in MFC due to time constraint.

RawCoder

Re:First, learn TCP/IP!

Masaaki Onishi20-Oct-01 11:51

Masaaki Onishi

20-Oct-01 11:51

Hello, the codegurus around the world.

First, you had better understand the concept of TCP/IP.
Server idnetifies the client with IP address and the port number.

This means that the client machine is assigned to the different IP address,
so server can understand the different client with IP address.
So, you may need the other code to restore IP addresses with the current access to the server, and differntiate the incoming socket with IP address.
(I think that this works, but I never implement this level of code. Dead | X|

)

Have a nice day!

-Masaaki Onishi-

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