C / C++ / MFC

Re: adress value of pointer NULL

5-May-03 4:58

What warning level are you using?

Joaquín M López Muñoz5-May-03 3:22

Joaquín M López Muñoz

5-May-03 3:22

What do you understand by "address value"? In most compilers, a null pointer, when converted to a number (an int, for instance), yields 0. Strictly speaking, this does not mean that a null pointer point to the address 0x00000000 (the standard marks as undefined conversion from pointers to integral values), although for some purposes you can assume this.

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

CFileDialog implementation...

macmac385-May-03 2:19

5-May-03 2:19

Hi,

i made this "File save as.." dialog window but after this i don'really know how to insert or to connect the given name to my saving function which is in another dialog window?

CString szlstfile = fileDlg.GetPathName(); //MainFrm.cpp

SaveStream(szlstfile); //ContrDlg.cpp

Thanks, Mark

jmkhael5-May-03 3:00

jmkhael

5-May-03 3:00

either open the File SAve as from ur dialog or make a member variable, and set it from the outside using a reference or a pointer to ur dialog

Papa

while (TRUE)
Papa.WillLove ( Bebe ) ;

macmac385-May-03 3:37

5-May-03 3:37

Hmm, sounds tricky..
I make a member variable(m_filename). Do u have a code snip for that?

Thanks, Mark

jmkhael5-May-03 4:16

jmkhael

5-May-03 4:16

in ur class:

class urClass
{
private:
CString m_fileName; /*(or array of char)*/
public:
void SetFileName ( CString fileName ) ;
};

and from another part of the world where this compile:

urClass object;

...
object.SetFileName ( "whateverPathToSet" ) ;

Papa

while (TRUE)
Papa.WillLove ( Bebe ) ;

David Crow5-May-03 4:02

5-May-03 4:02

What you have looks fine. Presumably SaveStream() will do something with the filename passed to it. What seems to be the problem?

macmac385-May-03 4:05

5-May-03 4:05

Hi,
the problem is to pass the filename from MainFrm.cpp to ControlDlg.cpp

Thanks, Mark

David Crow5-May-03 4:12

5-May-03 4:12

Passing variables from one file to another is undefined. I assume you have a class defined in ControlDlg.cpp (e.g., CControlDlg) with at least one public method (e.g., SaveStream). In your CMainFrame class, you'll need an instance of the CControlDlg class, unless the method is static. Now it's just a matter of calling the CControlDlg's method, passing it the filename obtained from CFileDialog.

macmac385-May-03 5:02

5-May-03 5:02

Yes, thats right. I like to give the filename before data arrived.(it comes from the usb-port). The SaveStream() func is called during runtime when data arrives.
How i can do that? I think the filename(variable is stored in RAM)..

Thanks, Mark

David Crow5-May-03 5:12

5-May-03 5:12

Now you've really got me confused. In your OP, the filename was originally coming from CFileDialog::GetPathName(). You then wanted to pass that to the SaveStream() function.

Perhaps you could explain in detail what you are after rather than just offer bits and pieces that just get construed along the way.

Anonymous5-May-03 8:12

Anonymous

5-May-03 8:12

I am sorry but thanks for your time.

----------------------------------------------------------------------------
//MainFrm.cpp

void CMainFrame::OnDataSaveAs()
{

CFileDialog dlg(FALSE);

CControlDlg cd;

dlg.m_ofn.lpstrInitialDir = "F:";

dlg.DoModal();

if ( dlg.DoModal() == IDOK)
{

CString filename = dlg.GetPathName();
cd.SaveStream(filename); //doesn't work because no data at start
}
}
-----------------------------------------------------------------------
//ControlDlg.cpp includes the main code for scanner

void CControlDlg::OndataReady(LPUNKNOWN pDobj)
{

STGMEDIUM s;
long hint = 0L;
BOOL r = FALSE;

COleDataObject foo;
foo.Attach((LPDATAOBJECT)pDobj);

r = ReadStream(pDobj, s, foo);

if(r){

SaveStream(filename); //saving

}

}

I like the user to choose a filename when my app starts, because this is a control programm for a 3d scanner over USB. When my app starts the scanner takes some scans every few seconds. So if the user select a filename at the start there is no data for the file at the begining.

When the scanner sends the datafiles i like to save them incremently.
For example:

filename choosen is "File", then saved as:

File_1
File_2
File_3
....

..for this the prog has to know the last filename. This all i have to handle.

David Crow5-May-03 8:29

5-May-03 8:29

I assume that OnDataSaveAs() is called when the "Save As" button is clicked, or when the "Save As" menu option is selected. Since this is a user-defined action, it may not have happened by the time your program needs the name of an output file (i.e., when calling SaveStream() from within CControlDlg::OndataReady().

It sounds like you need to check for the existance of an output filename before saving the data. Something like:

CControlDlg::OndataReady()
{
    ...
    if (filename.IsEmpty() == TRUE)
    {
        CFileDialog dlg(FALSE);
        dlg.DoModal();
        filename = dlg.GetPathName();
    }
    ...
    SaveStream(filename); //saving 
}

You may need to remove like code from the CMainFrame::OnDataSaveAs() function.

File Extension SDI Application

Anonymous5-May-03 9:08

Anonymous

5-May-03 9:08

Thanks for all. I will try it out.

Daniel Strigl5-May-03 1:45

Daniel Strigl

5-May-03 1:45

I have a MFC SDI Application.
How can I set the file extension of the "Open File..." dialog?

Daniel Wink | ;)

---------------------------
Never change a running system!

macmac385-May-03 2:35

5-May-03 2:35

http://www.mindcracker.com/mindcracker/c_cafe/mfc/filedlg.asp

Daniel Strigl5-May-03 2:41

Daniel Strigl

5-May-03 2:41

Thanks for the link, but the SDI framework does automaticly open the "Open file..." dialog! And I am only want to change the file extension of this (automaticly called) dialog!

Daniel Wink | ;)

---------------------------
Never change a running system!

basementman5-May-03 5:26

basementman

5-May-03 5:26

Edit the resource string table entry to set the file extension(s) that your app recognizes. It is probably an entry with the ID of IDR_MAINFRAME. An example is below:

ServerMon\n\nServer\nMonitor Server List (*.msl)\n.msl\nServerMon.Document\nServer Document