C / C++ / MFC Discussion Boards

Re: standard scrollbar & scrollbar control

ashxly24-Dec-03 14:34

24-Dec-03 14:34

MailMonty,
thanks for your reply,
I have tried to use GetScrollRange but nothing happened,
the min&max of the range are both zero
but i want to get the range and scroll it exactly

have you any good idea?

Class Member Variables:instance Vs pointer

hehenoobhehe23-Dec-03 21:08

hehenoobhehe

23-Dec-03 21:08

I am in the process of reorganizing my code and came across and I came across a problem, as described in the subject line of this posting.

I have many classes that have instances of other classes as member variables. So including a forward declaration doesnt help, does it? Faced with these, I had the following options:
-Include the appropriate header in the header file that contains the class definition that has a member variable that is a class instance as opposed to a pointer to the class
-Change the member variable from being a class instance to a class pointer.

I have the following questions:
1) Which approach is *better* and why?
2) If you need to include the header and the forward declaration of the class doesnt help(which is reasonable) what do you do?
For now, Im using this

#ifndef __FILE_H<br />
#include "File.h"<br />
#endif

Thanks in advance.

Re: Class Member Variables:instance Vs pointer

Johnny ²23-Dec-03 23:30

Johnny ²

23-Dec-03 23:30

The best approach depends upon your program. Its generally easier to have the class instance rather than a pointer, as you dont then need to manage allocation/deallocation. Plus it will be a little faster as the variable will be allocated automatically with the class, as opposed to having to use the heap. I would only use a pointer if its being passed into the class (for example, a pointer to the parent)

How to get the text of the button on the ctoolbarctrl?

benben23-Dec-03 21:06

benben

23-Dec-03 21:06

Hi:
How to get the text of the button on the ctoolbarctrl?I try:CToolBarCtrl::GetButtonInfo(),but the text it returns is always empty.
TBBUTTONINFO tbinfo;
char szBuf[100];
tbinfo.cbSize = sizeof (TBBUTTONINFO);
tbinfo.dwMask =TBIF_IMAGE|TBIF_STYLE|TBIF_TEXT;
tbinfo.pszText = szBuf;
tbinfo.cchText = 100;
cTbCtrl->GetButtonInfo(pInfo->dwItemSpec,&tbinfo);//（CToolBarCtrl * cTbCtrl）

but the szBuf is always empty.How should I do?
Thanks
Benben

How detect of USB Web-Came connect on PC

trekhlebov23-Dec-03 20:44

trekhlebov

23-Dec-03 20:44

My goal is detecting USB Web-Came connection in my PC for correct video capture.
I use DirectShow for my work. I did enumerating videocapture devices and always getting identical result - Web Came is in system. Independing WebCame is plug in or plug out.

How can I do it yet?

Tav

Re: How detect of USB Web-Came connect on PC

Monty²23-Dec-03 23:51

Monty²

23-Dec-03 23:51

I Use this Code works all the while
what problem are you having ?

IEnumMoniker *pEm;
hr = pCreateDevEnum->CreateClassEnumerator(CLSID_VideoInputDeviceCategory,&pEm, 0);
pCreateDevEnum->Release();

if (hr != NOERROR) 
{
  MessageBox("Sorry, you have no video capture hardware");
  return FALSE;
}
pEm->Reset();

Live as if your were to die tomorrow. Learn as if you were to live forever.
-Mahatma Gandhi

Setting attributes of a file/folder

rohit.dhamija23-Dec-03 20:18

rohit.dhamija

23-Dec-03 20:18

Dear All,

I am developing an application for Windows 2000 in MFC VC++ Version 6.0. I need to set attributes (read only, hide, etc...) on a given file/folderd.Is there any Win32 API provided ?

Thanks a lot and Happy Christmas!!

Rohit

Re: Setting attributes of a file/folder

Monty²23-Dec-03 23:44

Monty²

23-Dec-03 23:44

Try _chmod

if( _chmod( "CHMOD.C", _S_IREAD ) == -1 )
      perror( "File not found\n" );
   else
      printf( "Mode changed to read-only\n" );

Live as if your were to die tomorrow. Learn as if you were to live forever.
-Mahatma Gandhi

Re: Setting attributes of a file/folder

valikac24-Dec-03 6:10

valikac

24-Dec-03 6:10

One solution is SetFileAttributes().

Kuphryn

Enable / disable a LAN adapter programmatically

Jayanta Basu23-Dec-03 18:37

Jayanta Basu

23-Dec-03 18:37

Hi,
I would like to enable / disable a NIC adapter from a user program. The driver is installed previously. Can someone point me to any function which can do that ?

I already have a working PassThru driver which to do some operations on the card.

Thanks !

Jayanta

Clipcursor Error

pranavamhari23-Dec-03 18:22

pranavamhari

23-Dec-03 18:22

hi,

Clipcursor is not working in XP.

RECT rcClip; // new area for ClipCursor
RECT rcOldClip; // previous area for ClipCursor
// Record the area in which the cursor can move.
GetClipCursor(&rcOldClip);
// Get the dimensions of the application's window.
GetWindowRect(&rcClip);
// Confine the cursor to the application's window.
ClipCursor(&rcClip);
// Process
....................
// Restore the cursor to its previous area.
ClipCursor(&rcOldClip);

whats wrong ?

regards
hari

Hari Krishnan

MFC's future

java_jedi23-Dec-03 17:46

java_jedi

23-Dec-03 17:46

I'm a recent cs graduate and studied MFC programming as an undergrad, and I'm curious to ask what is the future of MFC with the arrival of .NET? and what about COM as well? The reason i ask is whether i should invest the time in learning .NET. Your input would be greatly appreciated.

Re: MFC's future

pranavamhari23-Dec-03 18:14

pranavamhari

23-Dec-03 18:14

hi,
there is no threat to MFC in the near future. .NET will take some time to catch up.

There are some excellent articles in the 'Interview' section of codeproject that will answer this.

Hari Krishnan

Re: MFC's future

Michael P Butler24-Dec-03 2:49

Michael P Butler

24-Dec-03 2:49

To be blunt, MFC has no future. It will be around for a long time, due to the amount of legacy code but I think we can forget about Microsoft updating it to support the newer API's.

MFC has had its day, WTL and other modern frameworks are better tools for the job now.

.NET is still in its infancy but seems to be growing up fast. It appears that the next version of Windows will deprecate the Win32 API, making .NET the first choice API.

Michael

Snow is lying on the ground, and in the air the sleigh bells sound,
The frosted patterned window panes, it's British summer time again.
No, it's not, It's Christmas - Santa Claus in on the Dole (Spitting Image 1986)

How could I get back my Save.cpp ?

ljx23-Dec-03 16:42

ljx

23-Dec-03 16:42

Save.cpp is a file in my VC program, but after my system's reboot which is caused by one systems' exception, this file is covert to a binary file, when I open the file, system prompt
"this file is bianry and cannot be read "
000000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00…………
000010 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00…………
000020 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00…………
........

I want to know how to get back my CPP File?
Thanks!

Just do it !

Re: How could I get back my Save.cpp ?

Anonymous23-Dec-03 17:58

Anonymous

23-Dec-03 17:58

Re: How could I get back my Save.cpp ?

ljx23-Dec-03 18:29

ljx

23-Dec-03 18:29

Help!

Just do it !

Re: How could I get back my Save.cpp ?

Gary R. Wheeler26-Dec-03 5:17

Gary R. Wheeler

26-Dec-03 5:17

In VC6, in the File Open dialog, use the 'Open as' dropdown list and select 'Binary'.

In VS.NET, in the File Open dialog, click on the dropdown attached to the Open button and select Open With... Select Binary Editor from the list.

In either case, this will open the file in the IDE's binary editor, which lets you change the file contents in hex. Use this to examine and correct the problems in the file.

Good luck.

Software Zen: delete this;

Re: How could I get back my Save.cpp ?

ljx28-Dec-03 13:53

ljx

28-Dec-03 13:53

Where Coudle I Get IDE's binary editor?
Thanks

Just do it !

getting rid of "Not Responding" window titles

shultas23-Dec-03 16:33

shultas

23-Dec-03 16:33

Hello all.

I am fairly new to programming with Visual C++. I am currently using version 6.0. I have done a lot of work in VB in the past, and am trying to migrate over to VC.

I am wondering if someone can point me in the right direction here. I am just tinkering around at this point. I've got an MFC program, with a listbox. I found some code and modified it for my liking. It's just simple code that searches the c:\ drive for all files and folders. If it finds a folder, it searches that folder too. It adds all of the files/folders to the listbox (m_ListBox.AddString()) is what I'm using. I'm also doing an m_ListBox.UpdateWindow() after each addition to ensure the window shows the contents correctly.

The problem I am running into is that since there are so many files on the C: drive, it takes a long time for the program to find them all. It adds the items very fast to the listbox, but what is happening is it is "locking up" the program (so to speak). Not Responding will show up on the window title, and it does not allow me to go into the listbox and click on the UP/DOWN arrows to scroll through while it is working.

In VB, I would use the function "DoEvents" and that would cause the program to let other things happen meanwhile. I am wondering how I would go about doing this in VC+?

Any pointers or hints or links to some documents that may be able to help me would be very much appreciated.

-Shultas

Re: getting rid of "Not Responding" window titles

Monty²23-Dec-03 17:54

Monty²

23-Dec-03 17:54

You will have to create a worker thread via CreateThread and find files in that thread and then send a WM_USER message from that thread to ur window which will eventually add items in the list control Wink | ;)

Live as if your were to die tomorrow. Learn as if you were to live forever.
-Mahatma Gandhi

Re: getting rid of "Not Responding" window titles

Michael Dunn23-Dec-03 18:09

Michael Dunn

23-Dec-03 18:09

See this question[^] in the VC forum FAQ

--Mike--
Ericahist | CP SearchBar v2.0.2 | Homepage | 1ClickPicGrabber New v2.0! | RightClick-Encrypt
#include "witty-quote.h"

composing a bitmap buffer ??

azusakt23-Dec-03 15:10

azusakt

23-Dec-03 15:10

Hi friends,

I'm going to compose a new bitmap by myself, and I'm using buffer to store up the data inside bitmap. But I did it wrong, and I get conflicts on that. can somebody help me and teach me how to store up correct contents in buffer??

I just want to draw a black "cross" on the center of bitmap with (1024x1024 pixel)

  unsigned char  *mBuffer = NULL;
  int i;
  int     mByte = 1024/8;
  int     mWidth = 1024;  // 1024 pixel
  int     mHeight = 1024;

  for(i=1; i<=mHeight; i++)
  {
if(i< mHeight/2)
{
  memset(mBuffer+(i*(mWidth/2)), 0xff, 1);
}
    else if(i==mHeight/2)
    {
  memset(mBuffer+(i*(mWidth)), 0xff, mByte);
    }
else
{
  memset(mBuffer+(i*(mWidth/2)), 0xff, 1);
}
  }

forgive my stupid~, I really don't know how to store up the buffer..

thanks for help

Re: composing a bitmap buffer ??

John R. Shaw23-Dec-03 15:29

John R. Shaw

23-Dec-03 15:29

Forget the buffer appoarch!

Creating for latter use:
1) Create a display compatible device context (memory DC).
2) Create a compatible bitmap of the size needed.
3) Select the bitmap into the device context.
4) Use GDI to draw the cross on the bitmap.
5) Select the previous bitmap into the device contest.
6) Delete compatible device context.

If you are keeping a copy of the bitmap for latter use, then you are all set.
In OnDraw():
1) Create compatible device context (memory DC).
2) Select bitmap into DC.
3) Blit to window.
4) Select previous bitmap into DC.
5) Delete compatible DC.

If you do not need to keep a copy of the bitmap.
In OnDraw():
1) Create a display compatible device context (memory DC).
2) Create a compatible bitmap of the size needed.
3) Select the bitmap into the device context.
4) Use GDI to draw the cross on the bitmap.
5) Blit to window.
6) Select the previous bitmap into the device contest.
7) Delete compatible device context.

INTP

ideas?

hingis_fan23-Dec-03 14:03

hingis_fan

23-Dec-03 14:03

Hi
Any one have any ideas on how to determine the size of a directory and any subsirectories?

I tried creating a console application using the _findfirst()/_findnext() functions. I think there must be an easier way.

Thanks in advance for any sugestions/comments.

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