C / C++ / MFC Discussion Boards

Raghunandan S3-Apr-06 7:39

3-Apr-06 7:39

Hi All,
I want to develop an application in which my GUI supports multiple views(CRichEditView,CListView,CTreeView..).All the views are independent of each other. when any modification is done in any of the views,that view sends a notification to observer class and this class in turn would notify other views about the updation.Can some one tell how to design this in MFC.I want to make the design robust so that more views can be added with ease.

Thanks in advance
Raghu

Re: Multiple view updation

basementman3-Apr-06 7:49

basementman

3-Apr-06 7:49

See CDocument::UpdateAllViews()

onwards and upwards...

Checkbox button question

madmax00013-Apr-06 7:03

madmax0001

3-Apr-06 7:03

Hi,

I'm creating a checkbox button at runtime. How can I determine the size of the drawn checkbox in front of the text. Is there a method in CButton to do this or can I retrieve this with a function like ::GetSystemMetrics() ?
Additionally it would be fine if I also could get the space between the checkbox and the text.

Thanks

Re: Checkbox button question

David Crow3-Apr-06 7:08

David Crow

3-Apr-06 7:08

madmax0001 wrote:
I'm creating a checkbox button at runtime.

Any particular reason why you aren't doing this at design time?

"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: Checkbox button question

madmax00013-Apr-06 7:20

madmax0001

3-Apr-06 7:20

Hi,

yes. I'm writing a GroupCheckbox control (similar to http://www.codeproject.com/miscctrl/GenCGroupCheckBx.asp). So the CButton control must be placed at runtime on the groupbox control. But I want to make this work under Win2000 and XP with or without BS_FLAT style set. And I determined that with the BS_FLAT style set, the checkbox is a little bit bigger than without.

Re: Checkbox button question

David Crow3-Apr-06 7:39

David Crow

3-Apr-06 7:39

madmax0001 wrote:
So the CButton control must be placed at runtime on the groupbox control.

Right, but it doesn't have to be created at runtime. Create the checkbox at design time and simply move it into the correct location using MoveWindow() or SetWindowPos().

"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: Checkbox button question

includeh103-Apr-06 7:17

includeh10

3-Apr-06 7:17

Only suggestion:
resize your check-box by MoveWindow(), if u can see the check-box but can't see its text, the size should be right.

i think all OS use same size for the square image of check-box, so once u know the size, u can use it anywhere for forever.

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Integrating Visual C++ and Java

pwimmers3-Apr-06 6:43

pwimmers

3-Apr-06 6:43

I am using the JNI and can call methods in my C++ code. Now I need help going in the other direction. My c++ code need to send an update back to Java. I am using JDK1.5.0 so StubsPreamble no longer exists.

Pat

Re: Integrating Visual C++ and Java

includeh103-Apr-06 6:48

includeh10

3-Apr-06 6:48

one idea is to establish pipes between C++ and java apps, so you can get/send signals from/to C++ and java apps - communications between them.

AfxBeginThread

viperlogic3-Apr-06 6:38

viperlogic

3-Apr-06 6:38

i have a function that i want a worker thread to execute it, my function is of the type

bool wmi(IP)

Can i use AfxBeginThread() with this or can only void functions be called? how can i pass a variable back or do i have to use a pointer?

thanks

Re: AfxBeginThread

includeh103-Apr-06 7:01

includeh10

3-Apr-06 7:01

if u want to pass a variable back, u must use a pointer.

code is in this way:
...ThreadFunction(void*pv)
{
SomeClass*pc=(SomeClass*)pv;
pc->SomeVariableBack=...;
}

it may not be what u want ...

Re: AfxBeginThread

David Crow3-Apr-06 7:07

David Crow

3-Apr-06 7:07

viperlogic wrote:
Can i use AfxBeginThread() with this

Indirectly you can. Something like:

AfxBeginThread(ThreadProc);
...
UINT ThreadProc( LPVOID lpParam )
{
    wmi();
}

You'll likely need to use the second argument to AfxBeginThread() as a way to call or communicate with the wmi() function.

"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: AfxBeginThread

viperlogic3-Apr-06 7:39

viperlogic

3-Apr-06 7:39

thx for the reply

how would i implement a timer, so that after say 5secs if the thread hasnt finished, kill it?

Re: AfxBeginThread

David Crow3-Apr-06 7:51

David Crow

3-Apr-06 7:51

Use WaitForSingleObject() for this.

CWinThread *pThread = AfxBeginThread(..., CREATE_SUSPENDED);
pThread->m_bAutoDelete = FALSE;
pThread->ResumeThread();
...
switch(WaitForSingleObject(pThread->m_hThread, 5000))
{
    case WAIT_TIMEOUT:
        // need to kill the thread
        break;

    case WAIT_OBJECT_0:
        // thread has terminated on its own
        break;
}

"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: AfxBeginThread

viperlogic3-Apr-06 8:22

viperlogic

3-Apr-06 8:22

thx for the replys

i am having trouble implementing AfxBeginThread()

<br />
void CScanDlg::OnButtonScan() <br />
{<br />
   AfxBeginThread(ThreadProc);<br />
}<br />
<br />
UINT CScanDlg::ThreadProc(LPVOID pParam)<br />
{<br />
	if(wmi(strIP1))<br />
            return 0;<br />
         else<br />
            return 1;<br />
}<br />

what is wrong above, sorry about these questions but this is new to me

Re: AfxBeginThread

David Crow3-Apr-06 8:31

David Crow

3-Apr-06 8:31

viperlogic wrote:
i am having trouble implementing AfxBeginThread()...

Aside from not suppling enough arguments, what troubles are you having?

viperlogic wrote:
UINT CScanDlg::ThreadProc(LPVOID pParam)

Is this a static member?

"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: AfxBeginThread

viperlogic3-Apr-06 8:58

viperlogic

3-Apr-06 8:58

ok this is what i have..

static UINT CScanDlg::ThreadProc(LPVOID pParam); delcared in the header file

<br />
AfxBeginThread(ThreadProc,NULL,THREAD_PRIORITY_NORMAL,0,0,NULL);<br />

<br />
UINT CScanDlg::ThreadProc(LPVOID pParam)<br />
{<br />
	if(wmi(strIP1))<br />
		return 0;<br />
	else<br />
		return 1;<br />
}<br />

i get the following error
CScanDlg::wmi' : illegal call of non-static member function

Re: AfxBeginThread

David Crow3-Apr-06 9:09

David Crow

3-Apr-06 9:09

Try:

AfxBeginThread(ThreadProc, this);
...
UINT CScanDlg::ThreadProc( LPVOID pParam )
{
    CScanDlg *pDlg = (CScanDlg *) pParam;
 
    if (pDlg->wmi(strIP1))
        return 0;
    else
        return 1;
}

"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: AfxBeginThread

viperlogic3-Apr-06 9:33

viperlogic

3-Apr-06 9:33

thx, that worked

can explain why thou?

Garbled output using cerr in piped programs

Stian Andre Olsen3-Apr-06 5:56

Stian Andre Olsen

3-Apr-06 5:56

Recently, I discovered that using cerr from console programs that are linked together by a pipe can produce garbled output. I have made two test programs that illustrate the problem. I have also made two programs that use fprintf and stderr instead of cerr -- and the output is fine. Does anyone know how to avoid the garbled output (see below) while still using cerr?

The first two programs that use cerr for log messages are called StdOutCpp and StdInCpp. When executing the command "StdOutCpp | StdInCpp" I get the following output (varies a little bit from execution to execution):

StdOut: Printing to stdout...
StdOut: Printing byte 1...
StdOut: Byte 1 printed.
StdIn: Reading from stdin...
StdIn: Reading byte 1...
StdIn: Byte 1 read.
StdOut: Printing byte 250001...
StdOut: Byte 250001 pStdIn: Rrinted.
eading byte 250001...
StdIn: Byte 250001 read.
StdOut: Printing byte 500001...
StdOut: Byte 500001 pStdIrinted.
n: Reading byte 500001...
StdIn: Byte 500001 read.
StdOut: Printing byte 750001...
StdOut: Byte 750001 pStdrinted.
In: Reading byte 750001...
StdIn: Byte 750001 read.
StdOut: Finished printing to stdout.
StdIn: Finished reading from stdin.

As you can see from the above printout, some lines are mixed together.

The next two programs that use fprintf and stderr for log messages are called StdOutC and StdInC. When executing the command "StdOutC | StdInC" I get the following output:

StdOut: Printing to stdout...
StdOut: Printing byte 1...
StdOut: Byte 1 printed.
StdIn: Reading from stdin...
StdIn: Reading byte 1...
StdIn: Byte 1 read.
StdOut: Printing byte 250001...
StdOut: Byte 250001 printed.
StdIn: Reading byte 250001...
StdIn: Byte 250001 read.
StdOut: Printing byte 500001...
StdOut: Byte 500001 printed.
StdIn: Reading byte 500001...
StdIn: Byte 500001 read.
StdOut: Printing byte 750001...
StdOut: Byte 750001 printed.
StdIn: Reading byte 750001...
StdIn: Byte 750001 read.
StdOut: Finished printing to stdout.
StdIn: Finished reading from stdin.

A perfect output, exactly as I want it.

Code listings:

--- StdOutCpp.cpp begin ---
#include <iostream>
using namespace std;

int main(int argc, char* argv[])
{
int n = 1000000;
cerr << "StdOut: Printing to stdout..." << endl;
for (int i = 0; i < n; i++)
{
if (i % (n / 4) == 0) cerr << "StdOut: Printing byte " << i+1 << "..." << endl;
cout << 'A';
if (i % (n / 4) == 0) cerr << "StdOut: Byte " << i+1 << " printed." << endl;
}
cerr << "StdOut: Finished printing to stdout." << endl;
return 0;
}
--- StdOutCpp.cpp end ---

--- StdInCpp.cpp begin ---
#include <iostream>
using namespace std;

int main(int argc, char* argv[])
{
int n = 1000000;
cerr << "StdIn: Reading from stdin..." << endl;
for (int i = 0; i < n; i++)
{
if (i % (n / 4) == 0) cerr << "StdIn: Reading byte " << i+1 << "..." << endl;
cin.get();
if (i % (n / 4) == 0) cerr << "StdIn: Byte " << i+1 << " read." << endl;
}
cerr << "StdIn: Finished reading from stdin." << endl;
return 0;
}
--- StdInCpp.cpp end ---

--- StdOutC.cpp begin ---
#include <iostream>
using namespace std;

int main(int argc, char* argv[])
{
int n = 1000000;
fprintf(stderr, "StdOut: Printing to stdout...\n");
for (int i = 0; i < n; i++)
{
if (i % (n / 4) == 0) fprintf(stderr, "StdOut: Printing byte %i...\n", i+1);
cout << 'A';
if (i % (n / 4) == 0) fprintf(stderr, "StdOut: Byte %i printed.\n", i+1);
}
fprintf(stderr, "StdOut: Finished printing to stdout.\n");
return 0;
}
--- StdOutC.cpp end ---

--- StdInC.cpp begin ---
#include <iostream>
using namespace std;

int main(int argc, char* argv[])
{
int n = 1000000;
fprintf(stderr, "StdIn: Reading from stdin...\n");
for (int i = 0; i < n; i++)
{
if (i % (n / 4) == 0) fprintf(stderr, "StdIn: Reading byte %i...\n", i+1);
cin.get();
if (i % (n / 4) == 0) fprintf(stderr, "StdIn: Byte %i read.\n", i+1);
}
fprintf(stderr, "StdIn: Finished reading from stdin.\n");
return 0;
}
--- StdInC.cpp end ---

Stian

STL next_permutation

thepersonof3-Apr-06 5:11

thepersonof

3-Apr-06 5:11

Hi I've the following code to generate permutations of my vector v:

<br />
		while (next_permutation(v.begin(), v.end() ) ) { <br />
                    // Loop until all permutations are generated.<br />
		copy(v.begin(), v.end(), ostream_iterator<int>(cout, ""));

How can I make it output to a vector instead?
I know I need to change to ostream_iterator, but what to?

cheers

-- modified at 11:14 Monday 3rd April, 2006

Re: STL next_permutation

Taka Muraoka3-Apr-06 5:23

Taka Muraoka

3-Apr-06 5:23

back_inserter

0 bottles of beer on the wall, 0 bottles of beer, you take 1 down, pass it around, 4294967295 bottles of beer on the wall.

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InitThunk

HakunaMatada3-Apr-06 3:14

HakunaMatada

3-Apr-06 3:14

What does the CAuxThunk and CAuxStdThunk classes do? What purpose does InitThunk have and why do we have to pass a Procedure name to it? What does TMPF stand for and what does it do?

Thanks... Smile | :)

---
With best regards,
A Manchester United Fan

The Genius of a true fool is that he can mess up a foolproof plan!

Hot toconnect databases to dialog based project

swapna_signsin3-Apr-06 3:00

swapna_signsin

3-Apr-06 3:00

Hi friends,
I've done a project which is dialog based application.Now I need to connect databases.So how do I proceed now.Do Ineed to redo the whole project in SDI.Pls help me in solving this problem.

bye

swapna_signsin

Re: Hot toconnect databases to dialog based project

Waldermort3-Apr-06 3:05

Waldermort

3-Apr-06 3:05

What sort of database are you trying to connect to?

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