C / C++ / MFC

18-Sep-03 4:32

Hello.

I'm currently designing a user interface for a piece of physics software which is currently only able to run through DOS. I'm new to Visual C++, and haven't done much programming for windows before. I have created an SDI MFC using the MFC App Wizard. The main menu contains the items: File Edit Setup Help.

When the user clicks on Setup (which is not a pop-up menu, it acts more like a button), a modeless dialog box opens up. What I want to do is have the Setup option disabled until the user opens a file (File -> Open). I have found lots of information on how to disable/enable items contained within these menu options, but not on how to deal with the menu options themselves. I am pretty sure that I must make use of ON_ UPDATE_COMMAND_UI, I'm just not completely sure what to do.

Any help anyone could provide me would be greatly appreciated!

KaЯl18-Sep-03 4:58

18-Sep-03 4:58

Yep, that's the way to do it. Look at the excellent article of Michael Dunn, "The Code Project Visual C++ Forum FAQ"[^], you may find there some useful info.

HTH,

K.

Every gun that is made, every warship launched, every rocket fired, signifies in the final sense a theft from those who hunger and are not fed, those who are cold and are not clothed - Dwight D. Eisenhower

b_girl18-Sep-03 5:19

18-Sep-03 5:19

I have looked at that article, and I do have an CMainFrame::OnUpdateSetup(CCmdUI* pCmdUI) function (with the message map ON_UPDATE_COMMAND_UI(ID_SETUP, OnUpdateSetup)), but I don't know how to actually call this function.

I thought that I could use ON_COMMAND(ID_FILE_OPEN, OnFileOpen) and in OnFileOpen make some sort of call to the OnUpdateSetup which will activate the setup option if a file has been opened. I still don't understand how i'm supposed to code: if a file has been opened, enable the Setup option in the menubar.

KaЯl18-Sep-03 5:30

18-Sep-03 5:30

You don't have to explicitely call this method, the MFC framework will do it for you when needed and when CPU time available. Once the method declared, the only thing you have to do is to define the condition of sensitivity (pCmdUI->Enable(<<condition>)). the="" condition="" could="" for="" example="" be="" a="" boolean="" attribute="" set="" to="" true="" when="" file="" is="" opened.

hth,

k.=""

<hr="" color="#ADBDFF" width="60%" align="left" height="10%">

b_girl18-Sep-03 5:41

18-Sep-03 5:41

But how do I tell the MFC framework to do it when it's needed? I don't need the Setup option activated until a file is opened. So how do I do this? I understand that I don't have to explicitly call this method, but I do need to somehow indicate when I want the setup menubar option to become enabled.

This is what I have at the moment:
...
ON_UPDATE_COMMAND_UI(ID_SETUP, OnUpdateSetup)
ON_COMMAND(ID_FILE_OPEN, OnFileOpen)
...

void CMainFrame::OnUpdateSetup(CCmdUI* pCmdUI)
{
pCmdUI->Enable(true);
}

void CMainFrame::OnFileOpen()
{
CString fileName;

CString szFilter = "All Files (*.*)|*.*||";

CFileDialog cfd(true, NULL , NULL , OFN_HIDEREADONLY, szFilter, NULL);
cfd.DoModal();

fileName = cfd.GetFileName();

//this is where i want to say that if a file was selected
//enable the setup menubar option
}

KaЯl18-Sep-03 5:55

18-Sep-03 5:55

The MFC framework knows what OnUpdate... methods to call thanks to the message map.

Let's suppose you add a boolean attribute to the mainframe, called m_bFileOpen, set to FALSE in the constructor. Your code would be:

void CMainFrame::OnUpdateSetup(CCmdUI* pCmdUI)
{
pCmdUI->Enable(m_bFileOpen);
}

void CMainFrame::OnFileOpen()
{
CString fileName;

CString szFilter = "All Files (*.*)|*.*||";

CFileDialog cfd(TRUE, NULL , NULL , OFN_HIDEREADONLY, szFilter, NULL);
if(cfd.DoModal() == IDOK){

fileName = cfd.GetFileName();
m_bFileOpen = TRUE;
}
}

HTH,

K.

Steve S18-Sep-03 6:30

Steve S

18-Sep-03 6:30

For completeness, you might want to support resetting the flag on close.
If you were using MDI document view, you could have the main app see if the documents collection was empty instead.

Steve S

KaЯl18-Sep-03 6:35

18-Sep-03 6:35

You're right. But I think the app is a SDI one Roll eyes | :rolleyes:

;)

To be more accurate, I think the boolean should be attached to the document class, set to TRUE when OnOpenDocument succeeds, and set to FALSE on OnCloseDocument.

b_girl18-Sep-03 7:21

18-Sep-03 7:21

yeah, it is SDI...

and you're right, attaching the boolean variable to the Doc class would probably be best...

Thanks for all the help!!

b_girl18-Sep-03 7:14

how to code an edit for database?

18-Sep-03 7:14

Thanks for the help. One more question, I'd like the Setup option to appear greyed out when it is disabled. Is there something similar to:
pCmdUI->Enable(m_bFileOpen);

that will do this? I thought that by disabling it, it would automatically grey it out as well, but i was wrong.

coda_x18-Sep-03 4:20

coda_x

18-Sep-03 4:20

i want to add an edit to my database dialog using CDaoRecordset edit and CDaoRecordset update, what variables i need to declare and how to code it? (mi really poor at programming) OMG | :OMG:

Re: how to code an edit for database?

vcplusplus18-Sep-03 6:09

vcplusplus

18-Sep-03 6:09

Check out this web site

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/vctutor98/HTML/_gs_data_access_objects_.28.dao.29_.tutorial.asp?frame=true

GetFTPConnection and socket()- MFC one fails

ns18-Sep-03 4:10

18-Sep-03 4:10

This is puzzling me. With the MFC code, I get : cant connect, but the socket () code connects fine (both to same address of my secondary machine). So since I want to use the MFC GetFile() functionality and dont know the equiv using the socket() method, I am stuck. What should i look at? BTW the MFC code works fine with the microsoft ftp address, so I know the codes okay. But if it were something weird about my 2nd machines IP address, then the socket() code should not connect either! But it does!

Here is the one that cant connect:

m_pFtpConnection = InternetSession.GetFtpConnection ("130.109.184.xxx" );

and this one works:

dstsockaddr.sin_addr.s_addr = inet_addr("130.109.184.xxx");

// port portion of the adress

dstsockaddr.sin_port = htons(PORT);

// address family as Internet

dstsockaddr.sin_family = AF_INET;



dstsocket = socket(AF_INET, SOCK_STREAM, 0);

if (dstsocket == -1)
    perror("socket creation failure");


status = connect(dstsocket, (struct sockaddr*) &dstsockaddr, sizeof(dstsockaddr));

Thanks,
ns

Jagadeesh VN18-Sep-03 4:24

Jagadeesh VN

18-Sep-03 4:24

Are you connecting to the FTP port ??

"A robust program is resistant to errors -- it either works correctly, or it does not work at all; whereas a fault tolerant program must actually recover from errors."

ns18-Sep-03 4:30

18-Sep-03 4:30

Yikes! I didnt think about that. The IP address I got just by doing ipconfig on my machine. The socket() code has a PORT 2000, but my MFC code has no port specified. Hmmm... so what I need to do here is get a file from a remote machine whose IP address is given to me. I saw GetFile() and jumped on it, is it that maybe the ftp.microsoft.com IP add works because its an FTP IP address and mine is just a regular IP address? Confused!

Thanks,
ns
I am now looking into GetHTTPConnection................????

Steve S18-Sep-03 4:53

Steve S

18-Sep-03 4:53

So you're running an FTP server on port 2000 then?
If that's the case you can use the address:port notation

eg: "192.9.200.1:2000"

The FTP connection is trying to use the default target port of 21. If your FTP server is on a different port, then your client needs to know that!

Steve S