Re: SpinCtrl - C / C++ / MFC Discussion Boards

John M. Drescher10-Apr-03 5:29

10-Apr-03 5:29

Erik Juhl wrote:
I think the rule is that anything you create on the heap you have to free yourself.

Yes, anything you create on the heap you delete yourself. You could use some type reference counting pointer for this or call the delete yourself. I do the latter more often.

John

Re: STL deque question

Zdeslav Vojkovic10-Apr-03 5:27

Zdeslav Vojkovic

10-Apr-03 5:27

erase() calls destructor of contained objects, not delete. destructor of a pointer just destroys the pointer variable, not the underlying object. you have to delete allocated objects explicitly.

Re: STL deque question

Alvaro Mendez10-Apr-03 5:53

Alvaro Mendez

10-Apr-03 5:53

Use auto_ptr instead of the pointers directly:

std::deque< auto_ptr<Wave> > _wavePool;
std::deque< auto_ptr<Wave> >::iterator it;
 
auto_ptr<Wave> wav1(new Wave("D:\\waves\\v1.wav", true));
_wavePool.push_back(wav1);
wav1->Splash();
 
_wavePool.erase(it); // will destroy the auto_ptr object, thus deleting the Wave pointer.

Regards,
Alvaro

When birds fly in the right formation, they need only exert half the effort. Even in nature, teamwork results in collective laziness. -- despair.com

SetWindowLong()

ZarrinPour10-Apr-03 5:01

ZarrinPour

10-Apr-03 5:01

Hi:
i have an EditBox and i wanted to change the default style "Left To Right Reading Order" to "Right To Left..." at run-time so i used the

following code:

SetWindowLong(m_hWnd,GWL_EXSTYLE,WS_EX_RIGHT);

successfully,the style of editbox changed,But when i want to swith
between "RTL" To "LTR" ,the above function doesn't work!!! Confused | :confused:

in the other hand i used this code:

SetWindowLong(m_hWnd,GWL_EXSTYLE,WS_EX_LEFT);

But function didn't work.is there another way to achieve this effect?

Please help me.
Regards.

Re: SetWindowLong()

Alvaro Mendez10-Apr-03 6:03

Alvaro Mendez

10-Apr-03 6:03

Try it this way with ModifyStyleEx:

ModifyStyleEx(0, WS_EX_RIGHT);  // to set RTL
ModifyStyleEx(WS_EX_RIGHT, 0);  // to clear RTL

Regards,
Alvaro

When birds fly in the right formation, they need only exert half the effort. Even in nature, teamwork results in collective laziness. -- despair.com

SpinCtrl

act_x10-Apr-03 4:51

act_x

10-Apr-03 4:51

Can I Set up a Spin ctrl to vary the number in a Edit box from 0.0 to 5.0 in Increments of 0.5 ?

Re: SpinCtrl

PJ Arends10-Apr-03 9:27

PJ Arends

10-Apr-03 9:27

http://www.codeproject.com/miscctrl/numspinctrl.asp

Sonork 100.11743 Chicken Little

"You're obviously a superstar." - Christian Graus about me - 12 Feb '03

Within you lies the power for good - Use it!

Re: SpinCtrl

Heiko200310-Apr-03 10:42

Heiko2003

10-Apr-03 10:42

Hi,

Set the Spinboxrange from 0 to 10
(0->0, 1->0.5, 2->1, 3->1.5, etc)

You can use the DialogMethod OnVScroll

The Message is WM_VSCROLL

put this Code in the OnVSrollMethod

void YourClassName::OnVScroll(UINT nSBCode, UINT nPos, CScrollBar* pScrollBar){
CString str;

if(pScrollBar==GetDlgItem(IDC_SPIN_..)){ //Insert here you SpinID
str.Format("%.1f",(double)(nPos/2.0));
GetDlgItem(IDC_EDIT_SPINVALUE...)->SetWindowText(str);
}
}

hope this helps

Problem with WorkQueue

Martin_Viet10-Apr-03 4:46

Martin_Viet

10-Apr-03 4:46

Hello:

I´m using CWorkQueue ( <ahref="">http://www.codeproject.com/useritems/Work_Queue.asp )in my project. I´m making a new class which is inherited from CWorkBaseItem. So OverWrite the doWork method where I create a socket and send a message. Everything work ok,

but I can see that the WorkQueue doesn´t destroy the terminated threads.

Anybody know how i can free all threas which had terminated???? Confused | :confused:

el hombre arriesga su vida cada vez que elige y eso es lo que lo hace libre

Getting Systeminformations

Sendel10-Apr-03 4:46

Sendel

10-Apr-03 4:46

Hi, do someone know how to get Systeminformations (like Memory Usage, Device Information, CPU, Totalmemory) in Win32 C++ under WindowsXP / Windows 98 / Linux ?

My Ideas:
CPU
With an Highresolutiontimer i can calculate the CPU Speed (MHz) but not the Facturer...
I have found some sources for older cpus, but i can't detect newer ones and neither special attributes like do they use mmx or sse2...

VGA
With OpenGL I can retrieve Informations about the graphic adapter like extentions, current videomode. But I need Informations of video buffers (do they supply quadbuffer for iGlasses?) or video memory (128MB DDR, 93.2 MB free)

Thanks alot for reading this, may be there is anyone who can help me...

Sendel

Re: Getting Systeminformations

MarkyMark10-Apr-03 5:24

MarkyMark

10-Apr-03 5:24

You can get most system information you want.

Here's a way of calculating CPU speed. It's not 100% accurate but close enough:

#pragma warning( disable: 4035 )
inline unsigned __int64 GetCycleCount()
{
_asm
{
_emit 0x0F
_emit 0x31
}
}
#pragma warning( default: 4035 )

int GetCPUSpeed()
{
Sleep( 0 );
const unsigned __int64 ui64StartCycle = GetCycleCount();
Sleep( 1000 );
return static_cast<int>( ( GetCycleCount() - ui64StartCycle ) / 1000000 );
}

Re: Getting Systeminformations

Sendel10-Apr-03 7:08

Sendel

10-Apr-03 7:08

That's what i have done already, so what i have is:

Have:
CPU Speed, Graphiccard Vendor, Driver Information, current Videomode, supported extentions

Need:
CPU Vendor, CPU Supported Chipsets (mmx, sse etc), Total Physical System memory, Free Physical System Memory, Graphiccard Total Video Memory, Graphiccard Free Video Memory, Graphiccard Memory Type (DDR, SGRAM, SDRAM...), Graphiccard supported Buffers (Quadbuffer, Front/Back Buffer, GBuffer, TBuffer,...), Graphiccard supported Videomodes

But thanks alot for your help !

Sendel

Re: Getting Systeminformations

Dominik Reichl10-Apr-03 9:16

Dominik Reichl

10-Apr-03 9:16

Sendel wrote:
Need:
CPU Vendor, CPU Supported Chipsets (mmx, sse etc),

Perhaps this helps you:
http://www.codeproject.com/system/camel.asp[^]

Sendel wrote:
Total Physical System memory, Free Physical System Memory

http://codeproject.com/system/computerinfo.asp[^]

Detecting Graphiccard things is a bit harder. Have you tried the DirectX API?

-Dominik

_outp(0x64, 0xAD);
and
__asm mov al, 0xAD __asm out 0x64, al
do the same... but what do they do??

Re: Getting Systeminformations

Sendel10-Apr-03 10:19

Sendel

10-Apr-03 10:19

This is my solution: i don't know where I found this source, but its quite good: and with comments Poke tongue | ;-P

<br />
#include <mmsystem.h><br />
#pragma comment(lib, "winmm.lib")<br />
<br />
DWORD GetCPUSpeed() <br />
{<br />
	LARGE_INTEGER ulFreq, ulTicks, ulValue, ulStartCounter, ulEAX_EDX;<br />
<br />
	// Query for high-resolution counter frequency (this is not the CPU frequency):<br />
	if (QueryPerformanceFrequency(&ulFreq)) <br />
	{<br />
		// Query current value:<br />
		QueryPerformanceCounter(&ulTicks);<br />
		// Calculate end value (one second interval); this is (current + frequency)<br />
		ulValue.QuadPart = ulTicks.QuadPart + ulFreq.QuadPart;<br />
		// Read CPU time-stamp counter:<br />
		__asm RDTSC<br />
		// And save in ulEAX_EDX:<br />
		__asm mov ulEAX_EDX.LowPart, EAX<br />
		__asm mov ulEAX_EDX.HighPart, EDX<br />
		// Store starting counter value:<br />
		ulStartCounter.QuadPart = ulEAX_EDX.QuadPart;<br />
		// Loop for one second (measured with the high-resolution counter):<br />
		do <br />
		{<br />
			QueryPerformanceCounter(&ulTicks);<br />
		} while (ulTicks.QuadPart <= ulValue.QuadPart);<br />
		// Now again read CPU time-stamp counter:<br />
		__asm RDTSC<br />
		// And save:<br />
		__asm mov ulEAX_EDX.LowPart, EAX<br />
		__asm mov ulEAX_EDX.HighPart, EDX<br />
		<br />
		DWORD tmp = (DWORD) ((ulEAX_EDX.QuadPart - ulStartCounter.QuadPart) / 1000000);<br />
		timediff = tmp/10000000.0*0.001;<br />
		// Calculate number of cycles done in interval; 1000000 Hz = 1 MHz<br />
		return tmp;<br />
	} else {<br />
		// No high-resolution counter present:<br />
		return 0;<br />
	}<br />
}

Thanks for all information,
=Sendel=

CDao problem with 'create'

naradaji10-Apr-03 4:00

naradaji

10-Apr-03 4:00

Hi,

I kind of finished my MFC 6 Dao application and decided to test it in another PC (in my Pc it works fine), and it crashes!
It gives me an error exactly in the CDaodatabase::Create statement. The error is: "Internal Error". All the PC's I tried produce the same error except mine
All these PC's have the same version of Access installed.

What could be the problem?

Any help would be greatly appreciated!

-- narada

Re: CDao problem with 'create'

Carlos Antollini10-Apr-03 4:05

Carlos Antollini

10-Apr-03 4:05

You must to install the daosdk librarys....

Look into the CDs of VStudio. I believe that you can find it in the last cd....
Best Regards

Carlos Antollini.
Pi Five[^]Creator

Sonork ID 100.10529 cantollini

Re: CDao problem with 'create'

naradaji10-Apr-03 4:08

naradaji

10-Apr-03 4:08

So in the target machines I have to install the dao libraries? Are they dll files?
Do you know which ones?

-- narada

Re: CDao problem with 'create'

Carlos Antollini10-Apr-03 4:26

Carlos Antollini

10-Apr-03 4:26

You must to install de Jet Librarys.
The problem is VC++ doesn't use the same version of dao of Access, is for that you must to install the Dao librarys.

I saw into the last cd of VS 6.0. look into the cd number tree, you will find the daosdk folder, into it you will find the redist subfolder with tree more subfolder into it....
Install that Files....

Best Regards

Carlos Antollini.
Pi Five[^]Creator

Sonork ID 100.10529 cantollini

Re: CDao problem with 'create'

naradaji10-Apr-03 4:42

naradaji

10-Apr-03 4:42

Crystal clear!

Thanks so much!

-- narada

exceptions

Jonathan [Darka]10-Apr-03 3:56

Jonathan [Darka]

10-Apr-03 3:56

Hi all,

I am in the process of developing several C++ libraries but cannot decide on this issue.
Is it better to have your code return an error_code when an error occurs, or to throw an exception.

The case I am thinking of is when I am wrapping a windows api call, if the api call itself fails, should I throw an exception, or return an error like... XFC_ERR_APIFAILED and allow the developer to call an GetLastAPIError() method to get the error code returned by the api call....

What do you people think? Should I restrict my code to being using with exception handling (like STL), or not ?

regards,
Jonathan

Re: exceptions

Alvaro Mendez10-Apr-03 6:42

Alvaro Mendez

10-Apr-03 6:42

Exceptions, use them. They're great. They make your code a lot cleaner by:

1. Not requiring you to check for errors after every function call.
2. Grouping your error checking/handling code in the places where it makes sense.
3. Allowing your methods to return other more relevant information, instead of having to worry about always returning error codes.
4. Allowing you to receive not just an error code, but a descriptive message to go along with it, as well as whatever other information you want to provide.

Look at newer languages such as Java and C# and they all make extensive use of exception handling. It's the way to go.

Regards,
Alvaro

When birds fly in the right formation, they need only exert half the effort. Even in nature, teamwork results in collective laziness. -- despair.com

Getting the response headers

RED10-Apr-03 3:47

RED

10-Apr-03 3:47

Does anyone know how to get the headers the server sent back with a page in the WebBrowser control?

Execution question

Jump_Around10-Apr-03 3:45

Jump_Around

10-Apr-03 3:45

I want my application to be opened once at the time. 2 different processes of my application cannot be created. If my appliaction is run and I want to run it again the previously created application should be opened.

I am looking for some tutorials or a piee of code

Please help

Re: Execution question

Cedric Moonen10-Apr-03 3:49

Cedric Moonen

10-Apr-03 3:49

There are several article about that on this site !

Take a look at the Thread, Processes & IPC section Smile | :)

Re: Execution question

valikac10-Apr-03 7:47

valikac

10-Apr-03 7:47

One solution is mutex.

Kuphryn

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