How to refresh a particular region - C / C++ / MFC Discussion Boards

jmkhael18-Jun-04 4:03

18-Jun-04 4:03

Several choices:

-realloc
-One of the containers: Linked list, vector, CArray ...

Papa

while (TRUE)
Papa.WillLove ( Bebe ) ;

Re: Unknown size array

Member 111482118-Jun-04 8:07

Member 1114821

18-Jun-04 8:07

i think you should use vector, like this

for( ;; )<br />
{<br />
    result = extern_function();<br />
    if( result == 3 )<br />
        break;<br />
    my_array[i++] = extern_function_data();<br />
}

Re: Unknown size array

James R. Twine18-Jun-04 11:28

James R. Twine

18-Jun-04 11:28

Almost... std::vector::operator[] does not reallocate; calling it with an out-of-range index results in undefined behavior (std::vector::at(...) will throw an exception).

The OP should be using push_back to add to the vector. (Of course, they might want to preallocate some space for performance reasons...) The code then looks something like:

<br />
std::vector< int > my_array;        // "int" For Example...<br />
<br />
my_array.reserve( 32 );             // "32" For Example...<br />
for( ;; )<br />
{<br />
    result = extern_function();<br />
    if( result == 3 )<br />
        break;<br />
    my_array.push_back( extern_function_data() );<br />
}

Peace!

-=- James
Tip for SUV winter driving survival: "Professional Driver on Closed Course" does not mean "your Dumb Ass on a Public Road"!
Articles -- Products: Delete FXP Files & Check Favorites

Re: Unknown size array

Member 111482118-Jun-04 15:42

Member 1114821

18-Jun-04 15:42

sure, i make a wrong.
if it's map it's right.

hi

what are the available DDE Server Data Format to write to Excel

swerajan18-Jun-04 2:55

swerajan

18-Jun-04 2:55

I am writing a DDE server in VC++ to write data to Excel. I had seen some where the use of XlTable format. but that is not working well for me. Is there a better format than that i can use.

Even more Serialization!

Anonymous18-Jun-04 2:54

Anonymous

18-Jun-04 2:54

I have posted a couple of questions already on this subject and am understanding it now all the better. I have my code working but wonder what others would think of what I have.

It is the library object which contains a list of subjects. Each subject contains a list of books. I serialize the library to disk which works well. For an example when I store my library object I also write the number of subjects it contains. When I restore the library I then dynamically allocate new subjects the number of which I read from the data file. I can then add new subjects with a member function like this -

CLibrary::addSubject(const CSubject *subject)
{
  CSubject *pSubject = new CSubject();
  pSubject->name = subject->name;
  // ... copy books in subject
}

I still wish to know though that what does CObject give me that I do not have to write myself anyway? I know it has other benefits like RTTI but what does it give for serilization? I just seem to have to write lots of code and CObject just is there doing nothing Confused | :confused:

Re: Even more Serialization!

Blake Miller18-Jun-04 4:19

Blake Miller

18-Jun-04 4:19

CObject is the base class that has the virtual functions you are overriding.
It has the RTTI that the serialition subsystem uses to serialize and deserialze objects properly, especially ones it builds on the fly - meaning it has to create the objects that are serialized that your object contains.

If I don't plan to serialize or RTTI a class, then I uusally don't derive it from CObject myself.

How to refresh a particular region

Arun AC18-Jun-04 2:29

Arun AC

18-Jun-04 2:29

Hai all,

I am doing a VC project invloving graphics.

While drawing a graphical object(say ellipse) on mousemove,
the whole screen is refreshed.

All the previously drawn objects are redrawn.
Consequently, the application slows down.

I am trying to refresh the particular region of the current object(ellipse) with InvalidateRect().

Please help me in solving this problem with InvalidateRect().
Or is there any other way to solve this problem?

With thanks,
Arun

Re: How to refresh a particular region

Ravi Bhavnani18-Jun-04 2:42

Ravi Bhavnani

18-Jun-04 2:42

InvalidateRgn()

/ravi

My new year's resolution: 2048 x 1536
Home | Articles | Freeware | Music
ravib@ravib.com

Re: How to refresh a particular region

Johan Rosengren18-Jun-04 4:37

Johan Rosengren

18-Jun-04 4:37

I'm doing stuff like this in http://www.codeproject.com/miscctrl/diagrameditor.asp[^] where I find the performance quite ok. I'm updating all of the screen, but I do use double buffering. So, this might be a solution for you - create a memory CDC, draw all objects to it, and blit the whole mess to the screen in a single BitBlt.

Re: How to refresh a particular region

John R. Shaw18-Jun-04 9:32

John R. Shaw

18-Jun-04 9:32

OnEraseBkgnd():
return TRUE; // do all drawing in OnDraw()

OnLButtonDown():
pointAnchor = point;
rectCurrent.Set(point.x,point.y,point.x+1,point.y+1);
InvalidateRect(rectCurrent);

OnMouseMove():
rectNew.Set(pointAnchor.x,pointAnchor.y,point.x,poin.y);
rectNew.NormalizeRect();
rectNew.bottom++;
rectNew.right++;
rectCurrent.UnionRect(rectCurrent,rectNew);
InvalidateRect(rectCurrent);
rectCurrent = rectNew;

OnDraw():
Normaly in the above you would have been drawing to a bitmap via a memory DC.
BitBlt(...);
ExcludeClipRect(bitmapRect); // area where you blited the bitmap
CRect rcClip;
pDC->GetClipBox(&rcClip);
pDC->FillSolidRect( // fill in background
rcClip.left,rcClip.top,rcClip.Width(),rcClip.Height(),
::GetSysColor(COLOR_WINDOW));

With that said check out the article CExBitmap, it was designed to be used in a paint program.

Good luck!

INTP

Urgent Named Pipe issue

A T I F18-Jun-04 1:48

A T I F

18-Jun-04 1:48

I am trying to use named pipe to transfer data between two process. I have called the following code

<br />
	HANDLE hPipe; <br />
	LPTSTR lpszPipename = "\\\\.\\pipe\\DataTransferPipe"; <br />
<br />
    hPipe = CreateNamedPipe( <br />
		lpszPipename,             // pipe name <br />
		PIPE_ACCESS_DUPLEX,       // read/write access <br />
		PIPE_TYPE_MESSAGE |       // message type pipe <br />
		PIPE_READMODE_MESSAGE |   // message-read mode <br />
		PIPE_WAIT,                // blocking mode <br />
		PIPE_UNLIMITED_INSTANCES, // max. instances  <br />
		1024,                  // output buffer size <br />
		1024,                  // input buffer size <br />
		18000,             // client time-out <br />
		NULL);                    // no security attribute <br />
	<br />
	if (hPipe == INVALID_HANDLE_VALUE) <br />
	{<br />
		MessageBox("Error creating named pipe", "Named Pipe Error"	, MB_OK);<br />
		return;<br />
	}<br />
	<br />
	bool bConnected = ConnectNamedPipe(hPipe, NULL) ? TRUE : (GetLastError() == ERROR_PIPE_CONNECTED); <br />

I want the system to be that if no client connect for say 3 sec the call ConnectNamedPipe should return false. Is this possible....how. In the above code it just locks on the ConnectNamedPipe call

Re: Urgent Named Pipe issue

vcplusplus18-Jun-04 3:35

vcplusplus

18-Jun-04 3:35

BOOL SetNamedPipeHandleState(
  HANDLE hNamedPipe,             // handle to named pipe
  LPDWORD lpMode,                // pointer to new pipe mode
  LPDWORD lpMaxCollectionCount,  // pointer to maximum collection count
  LPDWORD lpCollectDataTimeout   // pointer to time-out value
);

Removing Non-Client area of a window

alexei_p18-Jun-04 1:36

alexei_p

18-Jun-04 1:36

How can I remove non-client area of a window (border & title), which belongs to another process (separate application)? I have only HWND of that window, and cutting its DC using SetLayeredWindowAttributes() with LWA_COLORKEY, to get some specific shape, but all non-client area remains as an ugly frame. So I need to remove it somehow.
Note: the window is created by existing application, and I can’t change its code

Re: Removing Non-Client area of a window

Ravi Bhavnani18-Jun-04 2:43

Ravi Bhavnani

18-Jun-04 2:43

You might want to try hooking the window and handling WM_NCPAINT.

/ravi

My new year's resolution: 2048 x 1536
Home | Articles | Freeware | Music
ravib@ravib.com

Handling of window opening

alexei_p18-Jun-04 1:33

alexei_p

18-Jun-04 1:33

1) How to handle opening of a window, which belongs to another process (separate application)? The window has unique title, but not unique class. I need more intelligent way, than just calling FindWindow() from infinite loop

2) How can I monitor and handle closing/terminating of that window, after I found it?

Re: Handling of window opening

Rodrigo Pinto Pereira de Souza18-Jun-04 1:48

Rodrigo Pinto Pereira de Souza

18-Jun-04 1:48

Hook mechanism.
I don't know properly how to program to detect window open, but I know that is the most efficently way to detect.
Look in codeproject for hook. I think that you will have success ...

regards Cool | :cool:

Rodrigo Pinho Pereira de Souza

free pointer problem

mufasa218-Jun-04 1:00

mufasa2

18-Jun-04 1:00

I have the following code:

typedef double* configPt;
configPt* configurations;
configurations = (configPt*)malloc(sizeof(configPt));

for(int i=0;i < max;i++)
{
configurations[i][0]=/*whatever*/
configurations[i][1]=/*whatever*/
}
/*Operations with the aid of configurations*/
free (configurations);

Well, when the program arrives to the free function, it crashes and i dont know why.

Re: free pointer problem

jmkhael18-Jun-04 1:15

jmkhael

18-Jun-04 1:15

double** configurations;
configurations = (double**)malloc(sizeof(double*));
Here you are allocating a pointer to a pointer to double

for(int i=0;i < max;i++)
{
configurations[i][0]=/*whatever*/
configurations[i][1]=/*whatever*/
}
Here you are writing to a non allocated memory.

I would go for:

double **ppdDoubleMatrix = (double **) calloc(iRows, sizeof(double *));
if(ppdDoubleMatrix)
{
for (iRowsCounter = 0; iRowsCounter < iRows; iRowsCounter++)
{
ppdDoubleMatrix[iRowsCounter] = (double *) calloc(iColumns, sizeof(double));
}
}

Freeing it like so:

for (iRowsCounter = 0; iRowsCounter < pxThis->iRows; iRowsCounter++)
{
if (ppdDoubleMatrix[iRowsCounter])
{
free(ppdDoubleMatrix[iRowsCounter]);
ppdDoubleMatrix[iRowsCounter] = NULL;
}
}

// Free the pointer
free(ppdDoubleMatrix);
ppdDoubleMatrix = NULL;

Papa

while (TRUE)
Papa.WillLove ( Bebe ) ;

Re: free pointer problem

Rodrigo Pinto Pereira de Souza18-Jun-04 1:54

Rodrigo Pinto Pereira de Souza

18-Jun-04 1:54

for(int i=0;i < max;i++)
{
free(configurations[i][0]);
free(configurations[i][1]);
}

Enjoy it Cool | :cool:

Rodrigo Pinho Pereira de Souza

Using VC++6 .dll and .lib in VC.NET

Freddie Code18-Jun-04 0:58

Freddie Code

18-Jun-04 0:58

I'm trying to use a .dll and .lib that was created in VC++6 with a new VC.NET project. I add the .dll and .lib to the linker options and #include the cooresponding .h file to the project. I can't get the program to recongnize the function in the .dll and .lib correctly. It seems that .NET does not like the way the functions in the .h file are declared, or something?

Is there something new in VC.NET that I need to know with regards to using .lib and .dll?

Help! Thanks...

Using dll...

uniqueworld18-Jun-04 0:40

uniqueworld

18-Jun-04 0:40

I have a dll port.dll .I don't know how to use them in VC++.
I use dumpbin tool but I can't use them. Help me doing this.
Please tell me in detail.

Re: Using dll...

irshad_bukhari18-Jun-04 3:45

irshad_bukhari

18-Jun-04 3:45

Hi,

Below link has a very useful tutorial related to
DLL implementation in VC++ 6.

http://www.codeproject.org/dll/XDllPt1.asp

Hope it will be useful to you.

Best Regards,
Irshad

general question about network traffic detection

SireNexus17-Jun-04 23:27

SireNexus

17-Jun-04 23:27

Hello,

i want to develop a tool for winXP that dynamically
limits Intenet (IP) bandwith on a LAN host (LAN connected to Internet via router).
the tool should run on all LAN clients and send
information about the current IP traffic on the client to the other clients. with this information it should limit the bandwith to a predefined value, if the other clients need full bandwith, too.
for example: if three clients need full bandwith all
get limited to 1/3 of the full bandwith available.
if just one client need full bandwith it should get all.

thats the theory.

to manage this, i need to detect the current ip traffic on a client.
searching the web brought me to MS IpHlpApi.lib
but it only detects IP datagram amounts, not the real size if an ip-packet.

next solution is ip-packet sniffing, but this need
as far as i now, developing a kernel mode driver.

i know about pcap library for packet sniffing task
but it doesnt allow packet manipulation.
i dont need packet manipulation for my task, but
ive got another project in mind that does, so i want to go the straight (maybe hard) way.

i thought about using MS Visual C++ with MFC and DDK

so my question:
what would you suggest for solving my problem?

best regards
Robert

Re: general question about network traffic detection

Trollslayer18-Jun-04 1:34

Trollslayer

18-Jun-04 1:34

This sounds like any firewall code would do that. Maybe there is somethnig on Sourceforge ?

Elaine Rose | [Rose]

The tigress is here Big Grin | :-D

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