C / C++ / MFC Discussion Boards

Re: OnSysCommand - cant find it in ClassWizard

Bijesh13-Aug-02 8:18

13-Aug-02 8:18

ns wrote:
But since this turns out to be a cumulative problem, I am going to weed them out and delete them, and NULL them. Is the NULL a good practice or unnecessary?
Thanks,

Its a good idea to NULL the pointer as soon as you delete it. You can combine that practice with checking for NULL before you use a pointer .

But.. it is very important to delete any memory(objects, variables etc) that you allocate with new. Smaller variables may not cause a problem initially, but they do accumulate like you said. Also if the application is used for long periods of time, the smaller memory allocations accumulate and cause a problem. So always 'delete' what you 'new'

Bijesh

--------------------------------------------------

except my member pointers

ns13-Aug-02 8:30

13-Aug-02 8:30

I've got several member variables that are pointers and get used all the time. I am new at this stuff (no pun) so I am afraid to delete these since I access them all the time - for example some of these are doc variables that I access from several places at several times. I am deathly afraid I'll mangle my app if I delete these in the wrong place. Other than these, I've cleaned up my code.

Thanks,
ns

Default font for dialogs in EVC resource editor...

Wes Jones12-Aug-02 14:11

Wes Jones

12-Aug-02 14:11

Hi all,

Whenever I insert a new dialog resource into my project, the dialog's font is System 8, which makes the dialog look odd when it's displayed. I'd like it to default to MS Sans Serif 8, which is what it used to be(I think). How can I change the default font for dialog resources? I'm using EVC.

Thanks!
Wes

Sonork ID 100.14017 wtheronjones

Re: Default font for dialogs in EVC resource editor...

Atlantys12-Aug-02 14:45

Atlantys

12-Aug-02 14:45

Open the .rc file up in a text editor (notepad works),

look for the text for the dialog you want to change that looks similar to this:

IDD_ABOUTBOX DIALOGEX 0, 0, 140, 57
STYLE WS_POPUP | WS_CAPTION 
EXSTYLE WS_EX_CAPTIONOKBTN
CAPTION "About MyDialog"
FONT 8, "System"

and change the last line to be FONT 8, "MS Sans Serif"

I've never done this myself, but it should work. Big Grin | :-D

Re: Default font for dialogs in EVC resource editor...

Wes Jones12-Aug-02 16:40

Wes Jones

12-Aug-02 16:40

thanks for the post. that'll work for a single dlg. I can also get the same effect w/ the property dialog...on the General tab there's a btn to change the font. I'm kinda hoping to figure out the way to set the default font used for dialogs each time one is inserted.

thanks!
Wes

Sonork ID 100.14017 wtheronjones

ListView problem

Steve L.12-Aug-02 14:07

Steve L.

12-Aug-02 14:07

I want a program where there is a a list on the left part of the window and a edit control on the right. I can get the edit control, but not the list control. I tried having my program starting with the explorer view, set when I made a new program, and changing all the CTreeView to CListView. That gave me all the CListCtrl functions but I can't get the colums of the lists with the titles to appear. How can I get them to show? Should I be taking a different approach?

-Raffi

Re: ListView problem

Shog⁹12-Aug-02 14:24

Shog⁹

12-Aug-02 14:24

Make sure the list is in report view mode
Make sure you've added columns *before* trying to add items
Make sure you've added items
Make sure the columns have greater than 0 width

---

Shog⁹
If I could sleep forever, I could forget about everything...

Re: ListView problem

Steve L.12-Aug-02 14:45

Steve L.

12-Aug-02 14:45

Thanks for the tips. Works great now. Smile | :)

-Raffi

CFileDialog title

ns12-Aug-02 13:21

12-Aug-02 13:21

I want my Open dialog to have a title saying "Open Photograph"

What can I set in

CFileDialog pDialog(TRUE,"*.bmp", "*.bmp", OFN_HIDEREADONLY ,"Image Files(*.bmp;*.dib;*.gif;*.jpg;*.jpe;*.ico;*.cur)");

to do this?

Or is there some other property that can be set to do this?
Thanks,
ns

Re: CFileDialog title

Ravi Bhavnani12-Aug-02 13:48

Ravi Bhavnani

12-Aug-02 13:48

Do this:

pDialog.m_ofn.lpstrTitle = "Open Photograph";

before you display the dialog.

/ravi

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

Worker Thread...

fdmanana12-Aug-02 12:35

fdmanana

12-Aug-02 12:35

Hi, I am creating a file server aplication, which has a Worker Thread for Uploading a requested file by a client...

My Thread just works fine, it does what it was suposed to do...
The problem is that I want it to Close the socket after sending the file....
It seems that I get a runtime error whenever I call CAsyncSocket::Close in the Thread,
Outside the Thread I got no problem...
How can I close the socket inside the Worker Thread?

The code is something like that :

UINT UpLoad(LPVOID p) //worker thread
{
CMyDialog *d = (CMyDialog *) p;

//do the stuff for uploading the file...
//close the socket...
p->MySocket.Close();
return 0;
}

Then on a member function of CMyDialog class I call :
AfxBeginThread(UpLoad, this);

MySocket is a public member variable of the CMyDialog class and is an object from a derived class of CAsyncSocket which I created.
Thanks.

Re: Worker Thread...

JT Anderson13-Aug-02 7:38

JT Anderson

13-Aug-02 7:38

I haven't used any of the CSocket stuff for a long time, but my recollection is that CSocket objects are like CWnd objects in that you have to be really careful when you try to pass them from one thread to another.

I'd suggest that rather than passing the CAsyncSocket object from the main thread to the worker thread, you should "Detach" the socket from the CAsyncObject in the main thread, pass it by handle to the worker thread and then "Attach" it to a new CAsyncSocket object in the worker thread.

to parse a simple string

ns12-Aug-02 12:25

12-Aug-02 12:25

I have a variable (its a char*) which has the following stuff in it:

char * xyz = "C:\dir1\dir2\file.mdb, location1"

I want to put this into two variables which look like

char * dbName = "C:\\dir1\\dir2\\file.mdb"

and

char* location = "location1"

Should I first convert xyz into a CString, then do stuff to it (what exactly? to get two subCStrings then convert them back into char *s?

So I'm looking at Find, Right and Left:

If I had CString str = "abcd,efg"

Then int pos = str.Find(",") should give me zero based location 4.

then

CString leftstr = str.Left(pos) will be "abcd"

and

CString rightstr = str.Right(str.GetLength() - pos-1) will be "efg"

I cant test this out right now, so I'm wondering if this will work. Do you see any flaws with my numbers or thought process? and to do the '\' to '\\' I'd use Replace....

Thanks,
ns Unsure | :~

Re: to parse a simple string

Eddie Velasquez12-Aug-02 12:37

Eddie Velasquez

12-Aug-02 12:37

Try my CTokenizer[^] class. It might help you.

All of my opinions are correct, even when reality makes the mistake of disagreeing with me.

ASP.NET can never fail as working with it is like fitting bras to supermodels - it's one pleasure after the next - David Wulff

Re: to parse a simple string

Ravi Bhavnani12-Aug-02 12:48

Ravi Bhavnani

12-Aug-02 12:48

[Part 1]

There are many ways to parse the string. It depends on whether the input string is guaranteed to be of the specified form, or if you expect the form to vary. If the input string is going to be supplied by a user, you obviously can't guarantee that it will be of the correct format. That being said, here's a quick way to "extract" the filename and location from the source string:

char* xyz = ...
char* pDelimiter = strstr (xyz, ", ");
ASSERT (pDelimiter != NULL);
*pDelimiter = '\0';
char* dbName = xyz;

pDelimiter++;
pDelimiter++;
char* location = pDelimiter;

You'll notice I put "extract" in quotes. You haven't extracted anything. You've just made dbName and location point to the desired components.

[Part 2]
Let me try and clear some confusion about escaping the backslash character: you only need to do this to keep the compiler happy (i.e. when writing a string literal). You'd never programatically replace "\" with "\\".

/ravi

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

Thanks, ....

ns12-Aug-02 13:03

12-Aug-02 13:03

Pretty tricky.

try, catch - is this legal?

ns12-Aug-02 11:30

12-Aug-02 11:30

Is it okat to do this:

void SomeFunction()
{
      try
         {.....
         }
      catch
         {...
         }
      //more lines of code
       ................

      //another try-catch set:

      try
         {...
         }
      catch
          {....
          }

       //more lines of code

       return;

}

The reason is that if I throw 2 exceptions that are supposed to be of type int, then I have to have the catch block after each try in which I throw the int, because the catch will look like

catch(int i)

{
}
.
and if I put them all together at the end of the tries, it wont know which catch goes with which try....right?

Thanks,
ns

Re: try, catch - is this legal?

C^hris L^osinger12-Aug-02 11:36

C^hris L^osinger

12-Aug-02 11:36

maybe... i don't understand what you're asking.

if you want to catch an int, put a catch(int i) handler at the end of the "try" in which you want to catch it. you can nest trys, you can arange them sequentially, whatever. each is independent and can catch whatever you tell it to.

Conservative:
One who admires radicals centuries after they're dead.
-- Leo C. Rosten

image effects!

Re: try, catch - is this legal?

ns12-Aug-02 12:00

12-Aug-02 12:00

Well, you might not have understood my post since I'm not the clearest explainer, but you certainly answered my question. I didnt know if one function could only have one try, and a couple of catches
(both folllowing the try). So I see I can have as many try catch as I like:

try<br />
      catch<br />
      catch(...)<br />
<br />
      try<br />
      catch<br />
<br />
     try<br />
     catch<br />
     catch<br />
     catch<br />
<br />
     plain ordinary code<br />
<br />
     try<br />
     catch<br />
      <br />

thanks,
ns

Re: try, catch - is this legal?

Christian Graus12-Aug-02 12:53

Christian Graus

12-Aug-02 12:53

Yes, you can specify as many different catches as you like, but as soon as you put a catch(...), you're going to catch everything there, and nothing below ( I believe ).

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 )

Cats, and most other animals apart from mad cows can write fully functional vb code. - Simon Walton - 6-Aug-2002

Re: try, catch - is this legal?

C^hris L^osinger12-Aug-02 13:06

C^hris L^osinger

12-Aug-02 13:06

...for a single "try".

(just finishing the thought).

-c

Conservative:
One who admires radicals centuries after they're dead.
-- Leo C. Rosten

image effects!

Migrating from VC6 to VC7 Issue

Sydney Liles12-Aug-02 10:56

Sydney Liles

12-Aug-02 10:56

I am migrating a very large Win32 app from VC6.0 to VC7.0. I am down to one last issue (or so it seems -- these things have a way of hiding). This code works fine in VC6.0, but hangs indefintiely in VC7.0.

void QSWDoc::SetModifiedFlag(BOOL bModified)
{
CDocument::SetModifiedFlag(bModified);
CFrameWnd* pFrameWnd = (CFrameWnd*)AfxGetMainWnd();
if ( pFrameWnd != NULL )
pFrameWnd->OnUpdateFrameTitle(TRUE);
QSWController::GetQSWController().SendMessageToAllWindows(
UDM_DATACHANGED,NULL, NULL);
}

I have stepped through this code a hundred times. The issues is that pFrameWnd is not NULL, it has a valid value. However, pFrameWnd->m_strTitle's value is 0x00000000 <bad ptr="">. I confirmed that this is the source of the problem by substituting the following:
CString strTitle = pFrameWnd->GetTitle();
if( !strTitle.IsEmpty() ) ...

The hang occurs in the GetTitle() function when this code is substituted.

Sydney Liles
Software Engineer

Re: Migrating from VC6 to VC7 Issue

Shog⁹12-Aug-02 12:09

Shog⁹

12-Aug-02 12:09

Where is QSWDoc::SetModifiedFlag() being called from when the hangup occurs?

Where do you end up if you break execution during the hangup?

---

Shog⁹
If I could sleep forever, I could forget about everything...

Re: Migrating from VC6 to VC7 Issue

Sydney Liles12-Aug-02 12:20

Sydney Liles

12-Aug-02 12:20

I suppose I should have mentioned that this happens when the application is first launched.

QSWDoc::SetModifiedFlag() is being called from QSWDoc::OnNewDocument(), which calls CDocument::OnNewDocument().

If I step into or over the code pFrameWnd->OnUpdateFrameTitle(TRUE); I am absolutely hung and have to use Task Manager to close Visual Studio. At this point my call stack is referencing 00000000().

Sydney Liles
Software Engineer

Re: Migrating from VC6 to VC7 Issue

Shog⁹12-Aug-02 13:36

Shog⁹

12-Aug-02 13:36

Sydney Liles wrote:
QSWDoc::SetModifiedFlag() is being called from QSWDoc::OnNewDocument(), which calls CDocument::OnNewDocument().

Interesting... At this point (application launching) in a SDI app (maybe a MDI app too; not sure off-hand), the main window doesn't yet exist. So AfxGetMainWnd() *should* be returning NULL... Not sure why it isn't; you might want to trace through *that* call & see what's up. But in any case, you'll need to find a different place for your code; even in MFC6 you shouldn't be able to get away with this.

---

Shog⁹
If I could sleep forever, I could forget about everything...

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.