Linking a DLL file to MFC application - C / C++ / MFC Discussion Boards

avenger_sb255-Apr-04 6:43

5-Apr-04 6:43

Well, i am not about MFC, but using API u can do it the following way. Go through the code and i hope you can easily port it to MFC.

If you want to dynamically load a bitmap included as a resouce, use the following code:

<br />
HDC hdc,bdc;<br />
bdc=CreateCompatibleDC(hdc);<br />
hBmp=LoadBitmap(gloInst,"BMP_SYSTRAY");//gloinst is the hInstance parameter of WinMain and "BMP_SYSTRAY" is the string identifying the bitmap resource<br />
SelectObject(bdc,hBmp);<br />
BitBlt(hdc,0,0,200,100,bdc,0,0,SRCCOPY);<br />
DeleteDC(bdc);

The potential problem with this approach is that you cant pick bitmaps from the disk(any file) and bitmaps that have more than 256 colors.

Alternatively if you want to dynamically load any bitmap of any size and any bit-depth, use the following code:

When you process the WM_PAINT message, use the following code to draw the bitmap:
static BITMAPFILEHEADER * pbmfh ;
static BITMAPINFO * pbmi ;
static BYTE * pBits ;
static int cxDib, cyDib ;
static TCHAR szFileName [MAX_PATH], szTitleName [MAX_PATH] ;
HDC hdc ;
PAINTSTRUCT ps ;

WM_PAINT://For MFC use OnPaint(){//insert the following code}
hdc = BeginPaint (hwnd, &ps) ;
pbmfh = DibLoadImage (szFileName) ;//DEFINITION FOR THIS IS GIVEN BELOW, "szFileName is the PATH OF THE ".BMP" FILE e.g."c:\\test.bmp"
if (pbmfh == NULL)
{
MessageBox (hwnd, TEXT ("Cannot load DIB file"),"error",0) ;
return 0 ;
}
// Get pointers to the info structure & the bits
pbmi = (BITMAPINFO *) (pbmfh + 1) ;
pBits = (BYTE *) pbmfh + pbmfh->bfOffBits ;

// Get the DIB width and height
if (pbmi->bmiHeader.biSize == sizeof (BITMAPCOREHEADER))
{
cxDib = ((BITMAPCOREHEADER *) pbmi)->bcWidth ;
cyDib = ((BITMAPCOREHEADER *) pbmi)->bcHeight ;
}
else
{
cxDib = pbmi->bmiHeader.biWidth ;
cyDib = abs (pbmi->bmiHeader.biHeight) ;
}
SetDIBitsToDevice (hdc,
0, // xDst
0, // yDst
cxDib, // cxSrc
cyDib, // cySrc
0, // xSrc
0, // ySrc
0, // first scan line
cyDib, // number of scan lines
pBits,
pbmi,
DIB_RGB_COLORS) ;
EndPaint (hwnd, &ps) ;

BITMAPFILEHEADER * DibLoadImage (PTSTR pstrFileName)<br />
{<br />
     BOOL               bSuccess ;<br />
     DWORD              dwFileSize, dwHighSize, dwBytesRead ;<br />
     HANDLE             hFile ;<br />
     BITMAPFILEHEADER * pbmfh ;<br />
<br />
     hFile = CreateFile (pstrFileName, GENERIC_READ, FILE_SHARE_READ, NULL,<br />
                         OPEN_EXISTING, FILE_FLAG_SEQUENTIAL_SCAN, NULL) ;<br />
<br />
     if (hFile == INVALID_HANDLE_VALUE)<br />
          return NULL ;<br />
<br />
     dwFileSize = GetFileSize (hFile, &dwHighSize) ;<br />
<br />
     if (dwHighSize)<br />
     {<br />
          CloseHandle (hFile) ;<br />
          return NULL ;<br />
     }<br />
<br />
     pbmfh = malloc (dwFileSize) ;<br />
     if (!pbmfh)<br />
     {<br />
          CloseHandle (hFile) ;<br />
          return NULL ;<br />
     }<br />
<br />
     bSuccess = ReadFile (hFile, pbmfh, dwFileSize, &dwBytesRead, NULL) ;<br />
     CloseHandle (hFile) ;<br />
     if (!bSuccess || (dwBytesRead != dwFileSize)         <br />
                   || (pbmfh->bfType != * (WORD *) "BM") <br />
                   || (pbmfh->bfSize != dwFileSize))<br />
     {<br />
          free (pbmfh) ;<br />
          return NULL ;<br />
     }<br />
     return pbmfh ;<br />
}

^{Remember... testing & debugging are always part of programming ...so exterminate those stinking bugs}

Re: How to Load Bitmap Dynamically

GflPower5-Apr-04 16:12

GflPower

5-Apr-04 16:12

Hi

You can try to use the loadimage function ?

d

How to derive a MFC class from CMenu??

CPAVG5-Apr-04 4:45

CPAVG

5-Apr-04 4:45

I am a VC++ freshman, pls help me! Thanx a lot!!

How can I derive a MFC class from CMenu thus I can use Message Reflection ?

"Insert" Menu -> "New Class"
but I cannot see CMenu (and many other classes) in the "Base Class" edit control!!!!!

To be or not to be!

Re: How to derive a MFC class from CMenu??

Antony M Kancidrowski5-Apr-04 5:03

Antony M Kancidrowski

5-Apr-04 5:03

You could select CObject from the list, then when the class is created replace all CObject references with CMenu. Smile | :)

Otherwise generate a generic class based on CMenu and do all the message stuffs manually. Wink | ;)

Ant.

Re: How to derive a MFC class from CMenu??

CPAVG5-Apr-04 21:30

CPAVG

5-Apr-04 21:30

Thanx for you attention! Laugh | :laugh:

but it doesn't work.

1. No CObject in the Base Class list either.

2. What I want to do is using Message Reflection in my derived calss. If I choose generic class,I cannot use Class Wizard to add Message Reflection. I tried to derive from CStatic (or others),then replaced, but I got an error as follow:
error C2039: 'messageMap' : is not a member of 'CMenu'.
if no massagemap, how can I use Message Reflecion???

To be or not to be!

Re: How to derive a MFC class from CMenu??

Antony M Kancidrowski6-Apr-04 0:56

Antony M Kancidrowski

6-Apr-04 0:56

if no massagemap, how can I use Message Reflecion???

Quite, sorry the class has to be derived from CWnd in order to use message maps and reflection macros. D'Oh! | :doh:

Ant.

Re: How to derive a MFC class from CMenu??

CPAVG7-Apr-04 5:11

CPAVG

7-Apr-04 5:11

God bless me!

I wanted to write a neat owner-draw menu class that can process WM_MEASUREITEM & WM_DRAWITEM in itselt, but.....

Must I give up???

I add a virtual func. MeasureItem()to my menu class, but it doesnot work with the menu item opened a submenu, why??

To be or not to be!

Linking a DLL file to MFC application

chemipoo5-Apr-04 3:47

chemipoo

5-Apr-04 3:47

I have a DLL file that contains all the functions required to interact with a USB hardware interface device. There is also a corresponding header file which I got from the device manufacturer. I include the header file in my MFC application and put the DLL file in the debug folder of my project. But still I get compile error saying that it doesn't know anything about those functions I used from the DLL file. After some more research I think I need a .lib file and that I should link it to the project Dead | X|

. Using an already compiled DLL seems not as straight forward to me and so I'd really appreciate your kind help. Smile | :)

I'm beginning to know that I don't know.

Re: Linking a DLL file to MFC application

Antony M Kancidrowski5-Apr-04 4:53

Antony M Kancidrowski

5-Apr-04 4:53

Yes you will need the .lib file and the .h file in order to use the fuctions in the DLL, this is by all means the easiest way.

Without either of these you can prototype all functions you use and use LoadLibrary() to load the corresponding DLL.

Ant.

Re: Linking a DLL file to MFC application

george ivanov5-Apr-04 4:54

george ivanov

5-Apr-04 4:54

Don't use static linking, use dynamic loading of the dll functions like this:

typedef bool (*t_pFunc1)(LPCTSTR Param1, long Param2, bool Param3, ....);
t_pFunc1 m_pfFunc1;

HINSTANCE m_hLibraryInstance;
//Load dll library
m_hLibraryInstance = ::LoadLibrary(_T("Sample.dll"));
//load function
m_pfFunc1 = (t_pFunc1)::GETFUNCADDRESS(m_hLibraryInstance,"Func1");

//Dll call
m_pfFuncDll(param1, param2, param3, ... );

were rgrtgrtvrtrt rtrtb brt tyuhjghj hbhbnh hnjm 1234567?

Re: Linking a DLL file to MFC application

chemipoo5-Apr-04 5:50

chemipoo

5-Apr-04 5:50

Thank you guys. I stumbled upon some article that will guide me through linking it to the project. Blush | :O

Load DLL from other comp?

george ivanov5-Apr-04 3:24

george ivanov

5-Apr-04 3:24

Can I load dll library from other computer in LAN, using:
HINSTANCE LoadLibrary(LPCTSTR lpLibFileName);

were rgrtgrtvrtrt rtrtb brt tyuhjghj hbhbnh hnjm 1234567?

Re: Load DLL from other comp?

David Crow5-Apr-04 4:42

David Crow

5-Apr-04 4:42

The best way to answer that is to just try it. If LoadLibrary() fails, call GetLastError() to find out why.

"The pointy end goes in the other man." - Antonio Banderas (Zorro, 1998)

Re: Load DLL from other comp?

Navin5-Apr-04 9:07

Navin

5-Apr-04 9:07

If you use a UNC path you should be able to, as long as your programming is running under a user context that has access to the network share.

For instance:

HINSTANCE h = ::LoadLibray(_T("\\\\Computer\\Share\\MyDLL.dll"));

Note that if you are running under some weird user context (e.g., the System account) you might not have access to the network at all, in which case you certainly won't be able to load the DLL.

Sometimes I feel like I'm a USB printer in a parallel universe.

Video Capture Card

Flea Sp995-Apr-04 3:22

Flea Sp99

5-Apr-04 3:22

I'm working with a video framgrabber in Windows and having trouble getting access to pixel-level information. Confused | :confused:

I have found solutions to access the card through high-level Windows API (Video capture window) and then save the image as a .bmp, but this requires too much turn around time. Idealy I'd like to open the card and make direct calls that return the digitized video signal as pixels in an array. Any help or direction would be appreciated.

Flea

Machine Idle Time

Anonymous5-Apr-04 3:10

Anonymous

5-Apr-04 3:10

How do I find if the machine is idle for more than 10 mins
from my VC++ program

Jack

Re: Machine Idle Time

Michael Dunn5-Apr-04 4:56

Michael Dunn

5-Apr-04 4:56

If you're on 2K or later, use GetLastInputInfo()

--Mike--
Personal stuff:: Ericahist | Homepage
Shareware stuff:: 1ClickPicGrabber | RightClick-Encrypt
CP stuff:: CP SearchBar v2.0.2 | C++ Forum FAQ
----
Pinky, are you pondering what I'm pondering?
I think so Brain, but if we shaved our heads, we'd look like weasels!

Renaming a project

Trollslayer5-Apr-04 2:59

Trollslayer

5-Apr-04 2:59

I have a project with the base name "Shelf2".
Is there a straightforward way to rename everying in it to "Shelf3" for example. I have though of using find and replace in files but not sure if that would catch everything.
Ta.

Elaine Rose | [Rose]

The tigress is here Big Grin | :-D

Re: Renaming a project

Andrew Walker5-Apr-04 3:17

Andrew Walker

5-Apr-04 3:17

Depending on how often you need to reuse the code it may be just as easy to set up an appwizard. VC.NET minimised the custom appwizard nightmare from VC6. It takes a while to get them right but it's not too bad.

Extracting the common code to a shared library first made the job a lot smaller.

If you can keep you head when all about you
Are losing theirs and blaming it on you;
If you can dream - and not make dreams your master;
If you can think - and not make thoughts you aim;
Yours is the Earth and everything that's in it.

Rudyard Kipling

Re: Renaming a project(EDITED)

John M. Drescher5-Apr-04 5:41

John M. Drescher

5-Apr-04 5:41

Trollslayer wrote:
I have though of using find and replace in files but not sure if that would catch everything.

I have done this many times with VC6 projects. I load all the text files including project files and clw files into EditPad[^] and do a find and replace on all loaded documents. Then I have to rename all the files to match.

[EDIT]
I have also used the following tool in the past but I am not sure it renames everything: http://www.codeproject.com/tools/vsrename.asp?target=rename%7Cproject#xx774298xx[^]
[/EDIT]

John

Re: Renaming a project(EDITED BY ME)

Trollslayer5-Apr-04 6:00

Trollslayer

5-Apr-04 6:00

Thanks John Smile | :)

I tried VSRENAME and it worked fine :hug:

The tigress is here Big Grin | :-D

Re: Renaming a project(EDITED BY ME)

John M. Drescher5-Apr-04 6:14

John M. Drescher

5-Apr-04 6:14

Your welcome. And being a Monday I surely could use the hug. Smile | :)

John

IPersistStorage::Load() for Embeded object of Word Creates .doc file in Temp

anshumanshinde5-Apr-04 2:47

anshumanshinde

5-Apr-04 2:47

Hi!,

I am developing a container for embedding Miscosoft Word documents.
I am using CoCreateInstance()to create object,
after creation I set the clientsite and with the help of IPersistInterface::Load I load the storage, at this moment a temporary file having extension .doc is created in the Temp folder.
I want to avoid the creation of the temporary .doc file in the Temp folder.
and I also want to know the reason as to why the temporary .doc file is created.

Thanks

Anshuman

Re: IPersistStorage::Load() for Embeded object of Word Creates .doc file in Temp

Mike Dimmick5-Apr-04 6:37

Mike Dimmick

5-Apr-04 6:37

Probably Word creating it for its own purposes, for example to keep a working copy on disk for auto-recovery. You can't do anything about it, don't worry about it.

Stability. What an interesting concept. -- Chris Maunder

read a certain line from a text file

dairiseky5-Apr-04 2:44

dairiseky

5-Apr-04 2:44

I have a file that contains the following datas:
-2363824.109 (x position)
4870666.240 (y position)
2.18 (speed)
I want to read from this file either just the x position, either the y position, either the speed.
I did the following:

int main(int argc, char *argv[]){<br />
  <br />
	ifstream GPSFile; //mode lecture<br />
	GPSFile.open("C:\\My Files\\GPSFile\\GPSFile.txt", ios::in);//ouvre le fichier <br />
	//c'est le fichier où on écrit les datas du gps<br />
	double CataCoordX, CataCoordY;<br />
	double gpsx=0, gpsy=0;<br />
	while (!GPSFile.eof()){//tant que le fichier reste ouvert<br />
		if (GPSFile.rdstate() == ios::failbit){cout<<"ERROR, \n";}<br />
		///GPSFile.seekg(ios::beg); //go to the beginning of the file<br />
		GPSFile >> gpsx;//on lit<br />
		GPSFile >> gpsy;//on lit<br />
		CataCoordX=gpsx;//la première val devient les coord sur x<br />
	    CataCoordY=gpsy;//la deuxième val devient les coord sur y<br />
	}//endwhile<br />
	cout << CataCoordX <<endl;<br />
	cout << CataCoordY <<endl;<br />
	GPSFile.close();<br />
	return 0;<br />
}

This will print :
2.18
4.87067e+006
But me i want to print the first and the secon value. How to do this?

THX

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