Re: Still a little lost with GetActiveDocument() - C / C++ / MFC Discussion Boards

aah! Thats what I was looking for!

ns31-Jul-02 6:50

31-Jul-02 6:50

Many thanks! Precisely the sort of answer I was needing - its clear now!
Appreciate your help,
ns

Re: not clear why & is used

Ravi Bhavnani31-Jul-02 6:54

Ravi Bhavnani

31-Jul-02 6:54

It's checking if a specific bit is set.

In the following example, uMask can hold up to 32 distinct flags (since it's a 32 bit quantity). To check if bit 2 (i.e. decimal value 4) is set, we do:

unsigned long uMask = ...;
unsigned long uTest = 0x04;
if (uMask & uTest) {
   printf ("Bit 2 is set");
}

You wouldn't want to simply compare uMask with uTest using the == operator, because that simply tests if they are identical. So in your ADO example (btw I know nothing about ADO), you're checking if the connection happens to be open. If so, you're closing it.

You could write a function to do this check, thereby making the code more readable and maintainable. For example:

bool isAdoConnectionOpen
  (CAdoConnection* pConn)
{
  ASSERT (pConn != NULL);
  return ((pConn->State & adStateOpen) == adStateOpen)
}

You'd use the function in this manner:

if (isAdoConnectionOpen (pConn)) {
   pConn->Close();
}

/ravi

Let's put "civil" back into "civilization"
http://www.ravib.com
ravib@ravib.com

Re: not clear why & is used

PJ Arends31-Jul-02 8:08

PJ Arends

31-Jul-02 8:08

In addition to what others have said:

This construct also checks for multiple bits (ie adStateOpen is a combination of bits)

  11001111 - State
& 01000100 - adStateOpen
----------
  01000100 - result == adStateopen

and

  00001111 - State
& 01000100 - adStateOpen
----------
  00000100 - result != adStateOpen but is not false either

CPUA 0x5041

Sonork 100.11743 Chicken Little

"So it can now be written in stone as a testament to humanities achievments "PJ did Pi at CP"." Colin Davies

Within you lies the power for good - Use it!

Shared resources management

Antony B.31-Jul-02 5:40

Antony B.

31-Jul-02 5:40

I have to develop an application in Visual C++
that must connect itself to any type of LAN in order
to open a shared database.
This application must run on Win2K.
It can be not foreseen if the remote PC, where
the database is stored, manages a work group,
a domain or other rules.
I only know that the database is contained by a shared
folder.

What have I to foresee in my application ??

Which services or protocol have I to install in my PC ??

Still a little lost with GetActiveDocument()

NickOne31-Jul-02 5:22

NickOne

31-Jul-02 5:22

Hello all,

I've been reading the MSDN library stuff to try to figure out how GetActiveDocument works and I can't figure it out.

I have a string in my CDocument class called m_Filename.
I can access this variable in my View class with a GetDocument like this

CDisplayDIBDoc* pDoc = (CDisplayDIBDoc*)GetDocument();
if (pDoc)
{
(LPCTSTR)pDoc->m_Filename);
}

So I want to access this same variable in my CMDIChildWnd class that I made.
And I did this

CDisplayDIBDoc* pDoc = (CDisplayDIBDoc*)GetActiveDocument();
if (pDoc)
{
(LPCTSTR)pDoc->m_Filename);
}

Assuming it would work the same. I didn't override GetActiveDocument. Should I have?

I also rechanged that code with a !pDoc and a AfxMessageBox, and voila, the Message Box shows up, which means that I KNOW that pDoc is returning as a NULL.

How can I get to my m_Filename (a CString) variable in my Doc class from tmy CMDIChildWnd class?

Thanks a bunch

Re: Still a little lost with GetActiveDocument()

JennyP31-Jul-02 6:23

JennyP

31-Jul-02 6:23

Here is the magic bullet I found works:

CTtDoc *pDoc=(CTtDoc *)((CMainFrame *)AfxGetApp()->m_pMainWnd)->GetActiveFrame()->GetActiveDocument();

It came from a discussion on these message boards just a few days ago.

In your case, you can then access, of course, by:

pDoc->m_Filename

Good luck! Wink | ;)

JennyP

Re: Still a little lost with GetActiveDocument()

NickOne31-Jul-02 7:03

NickOne

31-Jul-02 7:03

Ok so I tired it like this:

CMyDoc *pDoc = (CMyDoc *)((CMainFrame *)AfxGetApp()->m_pMainWnd)->GetActiveFrame()->GetActiveDocument();

if(pDoc)
{

pDoc->m_Filename;

}

And this doesn't work.

I put
if(pDOc == NULL)
{
AfxMessageBox("pDoc is NULL");
}

and this worked, so pDoc is still Null and not the String in m_Filename

So either the string in m_Filename gets erased somewhere and set back to NULL, or I am doing something still wrong.

Any ideas?

NickOne

Re: Still a little lost with GetActiveDocument()

NickOne31-Jul-02 8:06

NickOne

31-Jul-02 8:06

Hello again,

Well I tried the code that I wrote above in a Dialog Window class that I added to the project.

In the Dialog window, it works correctly. Everytime, the m_Filename is accessed correctly.

BUT, in the CMDIChildWnd class that I added, it still shows up as a NULL. Why would this be??

i am really lost on this, and I really want to figure this out.

Thanks,

Nick

multipart file download...

behrang7931-Jul-02 5:02

behrang79

31-Jul-02 5:02

Dear memebers,

I'm searchnig for a source code of a "dwonload manager" program with pause/resume and multipart download capabilities.Please help me if know konw
any open source program in C/C++ or any document that could help me

thank you in advance

C1010: unexpected end of file while looking for precompiled header directive

Raskolnikov31-Jul-02 4:59

Raskolnikov

31-Jul-02 4:59

I have a .cpp file that compiles fine when used in a console app but gets errors when I include it in a MFC App.

d:\Visual C++.NET In 21 Days\Day 06 Dialogs\CMatrixTest.cpp(588): fatal error C1010: unexpected end of file while looking for precompiled header directive

I look up error 1010 and I get the increadibly useful result "The configuration registry key is invalid."

The file consists of a class definition that uses the standard template library. No main() or WinMain() function. I haven't included it yet in any other files.

Anyone have a clue as to what's going wrong because I sure don't.

Re: C1010: unexpected end of file while looking for precompiled header directive

RichB31-Jul-02 5:05

RichB

31-Jul-02 5:05

Raskolnikov,

I've had problems with a similar message before. Go to the offending file and delete any and all characters at the end after your last statement. When I have done this, it usually clears it up.

Good luck!

Rich

I hate Microsoft

Raskolnikov31-Jul-02 5:08

Raskolnikov

31-Jul-02 5:08

I looked and every other file in a MFC app had this line so I added it and the program compiled.

<br />
#include "stdafx.h"<br />

I hate Microsoft.
What does "The configuration registry key is invalid." have to do with no including "stdafx.h"?

Can anyone know why I need to add this header file to all my .cpp files?

Re: I hate Microsoft

Jim Crafton31-Jul-02 6:25

Jim Crafton

31-Jul-02 6:25

Raskolnikov wrote:
Can anyone know why I need to add this header file to all my .cpp files

THe simple answer: Precompiled headers

It makes a huge difference in compile times, however it is not hte most logical thing to use in the settings
You can turn it off for the whole project if you go to "Project Settings" and click the "C++ tab" and the "Precompiled Headers" category.
If you click on "Not using procompiled headers" it will get rid of this problem but considerably slow things down.
If you just want to shut it off for the file, then you can click on the file (still in the project settings dialog) and for the precompiled header settings just turn them off ONLY for the offending file.

If you are doing MFC stuff it is worth leaving them on

Re: I hate Microsoft

Raskolnikov31-Jul-02 15:58

Raskolnikov

31-Jul-02 15:58

I don't mind the feature now that I know what it does, but the error message bites. "must #include stdafx.h when using precompiled headers" or any error message that mentioned either stdafx.h or precompiled header would be better than a cryptic message about an invalid registry configuration key.

Maybe the message makes sense to the implementers, but error messages should be written at the users level of abstraction!

Re: I hate Microsoft

Christian Graus31-Jul-02 17:02

Christian Graus

31-Jul-02 17:02

The message was

fatal error C1010: unexpected end of file while looking for precompiled header directive

and it is not at ALL cryptic. Your precompiled header does not need to be called stdafx.h, and it's reasonable to consider that the user of a C++ compiler will either know what a precompiled header is, or be able to find out.

BTW you can also tell the compiler to automatically use precompiled headers with stdafx.h, and it will simply not use the precompiled headers where stdafx.h is not included. But it's usually better to include it everywhere, stdafx is a good central point to include libraries you want visible through the project, etc. For example, you'll find my stdafx is always going to include string, iostream, sstream, fstream, vector and algorithm with appropriate using statements as a minimum

Christian

We're just observing the seasonal migration from VB to VC. Most of these birds will be killed by predators or will die of hunger. Only the best will survive - Tomasz Sowinski 29-07-2002 ( on the number of newbie posters in the VC forum )

My bad I though Error lookup tool was for compiler errors..

Raskolnikov1-Aug-02 11:33

Raskolnikov

1-Aug-02 11:33

The compiler error was fine, what I was upset about was the result I got when I tried to find further informaiton about the error using the error lookup tool, which I know now has nothing to do with compiler errors.

Anyway I have been using C++ compilers for years, mainly with compand line compilers like gcc but I have never heard of precomiled headers or precomiled header directives. The Visual C++ .NET book I am just read fails to mention them.

Splash screen

hongheo7631-Jul-02 4:31

hongheo76

31-Jul-02 4:31

Hi,

Can anyone tell me how to make a Splash Screen using VC++ ?

I am used to the Visual Basic style :

frmSplash.show
do our initialization work
frmSplash.hide

With VC++, when I create a splash screen dialog box, then write:

CSplashDialog dialog;
dialog.DoModal();
Sleep(1000); /* or do my init stuff */
dialog.EndDialog();

It seems like the system gets stuck in the dialog.DoModal() function.

How to change the code ? Do I have to do my stuff inside my splash dialog ?

Thanks a lot

Re: Splash screen

Nish Nishant31-Jul-02 4:43

Nish Nishant

31-Jul-02 4:43

Show a modeless dialog. Once you've done your stuff, post a user-defined message to the modeless dialog and close it in the message handler. For more info on modeless dialogs see this article :-

http://www.codeproject.com/dialog/gettingmodeless.asp

Nish

Author of the romantic comedy

Summer Love and Some more Cricket [New Win]

Review by Shog⁹
Click here for review[NW]

Re: Splash screen

Tomasz Sowinski31-Jul-02 4:48

Tomasz Sowinski

31-Jul-02 4:48

If you're using VC6, go to Project/Add to project/Components and controls/Visual C++ components. There's a Splash Screen component which is ready to use.

Tomasz Sowinski -- http://www.shooltz.com

- It's for protection
- Protection from what? Zee Germans?

FtpGetFile Issue

RichB31-Jul-02 4:29

RichB

31-Jul-02 4:29

All,

I was wondering if anyone has had issues with FtpGetFile. This behavior is rather odd; the file is there but cannot be downloaded. I have had my remote user check out the file security/privileges; they appear to be in order. I would like to be able to provide more information. However, since this is happening at a remote site, I do not have more information. Does anyone have any ideas?

Thanks in Advance,

Rich

How to read the unicode string from a file?

Neha31-Jul-02 3:34

Neha

31-Jul-02 3:34

Hi,
How can i read the unicode string from a file?
Thanks
Neha

Modal dialogs fon't show after main dialog shuts down

Tre K Renegade31-Jul-02 3:31

Tre K Renegade

31-Jul-02 3:31

Hi people,

A small question.

In a dialog-based app, why is it impossible to start up a new dialog after the main dialog closes? (i.e. right after the DoModal returns in the app's InitInstance handler)

Even when you try to pop up a simple MessageBox it doesn't show. You can just hear the typical MessageBox 'Bling', but then the app shuts down.

Can anyone explain why this is the case? And what I should do to achieve my goal: showing a 'saving, please wait' dialog after the users hits finish in my wizard.

Thanks a lot for your help,

ren

Re: Modal dialogs fon't show after main dialog shuts down

Nish Nishant31-Jul-02 4:03

Nish Nishant

31-Jul-02 4:03

This article explains what you are looking for :-

http://www.codeproject.com/dialog/dlgboxtricks.asp

Scroll down to the last tip titled - "Show MessageBox after main dialog is dismissed"

The method described there works not only for msgboxes but also for further modal dialogs.

Nish

Author of the romantic comedy

Summer Love and Some more Cricket [New Win]

Review by Shog⁹
Click here for review[NW]

Re: Modal dialogs fon't show after main dialog shuts down

Tre K Renegade31-Jul-02 4:34

Tre K Renegade

31-Jul-02 4:34

Perfect.

Thanks a lot.

How to set font

Al_Pennyworth31-Jul-02 3:06

Al_Pennyworth

31-Jul-02 3:06

Hey, I posted this once and I am hoping to get some suggestions this time. If nobody knows, hey, that is life. I am trying to set the font/color, etc, for text in a multiline text editor. The user can highlight as many lines (or chars) as he/she wants, and then change all the text that has been selected to the font/color. The problem is that it is not working. I get the font characteristics, then call EM_SETCHARFORMAT with the SCF_SELECTION. According to MS website, this will change all the selected text. It doesn't. It seems, when there is a carriage return or word wrap of some kind, it cannot handle these characters. So it only changes 1 line. I do not know how to get around this. I have used EM_EXGETSEL and then send EM_EXSETSEL, this doesn't help either. Does anybody have any ideas? I have no clue how to get around the word break chars.

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