C / C++ / MFC Discussion Boards

Re: How can I post a user message from a Dialog box to the CDocument class?

Bram van Kampen11-Aug-08 15:17

11-Aug-08 15:17

Electronic75 wrote:
Hi, I tried but I couldn't because it requires that I have a member variable of dialog box in CDocument class, so I have to include CDialog header file in CDocument header file in that case I also need to define a member variable that points to CDocument so I also need to include CDocument header file in CDialog header file and this causes the compiler to cry loudly and gives hundreds of errors I even tried to prevent compiler form reading a header file recursively. like this:

Well, read up on your cpp. Ofcource the compiler (and largely the Framework) will object if you start adding items willy nilly to CDocument. After you eventually convince the compiler that way, the Linker will complain more loudly! (and should do so!)

The crucial issue is that you have derrived a class CMyDocument, from CDocument. Again, Read up on CPP, Place your Dlg Header in 'MyDocument.h"
and you can call it from CMyDocument (but NOT from CDocument except by virtual function.)

Regards, Smile | :)

Bram van Kampen

Re: How can I post a user message from a Dialog box to the CDocument class?

Electronic7511-Aug-08 17:59

Electronic75

11-Aug-08 17:59

Hi, My mistake from CDocument and CDialog I meant a CDocument/CDialog derived class i.e. CMyDocument/CMyDialog Blush | :O

and the code was like this,

#ifndef C_MY_DOC_H_
#define C_MY_DOC_H_
...//CMyDoc.H body
#endif

Regards,

Re: How can I post a user message from a Dialog box to the CDocument class?

Randor 10-Aug-08 17:31

Randor

10-Aug-08 17:31

Whats wrong with doing this from your Dialog:

CFrameWnd * pFrame = (CFrameWnd *)(AfxGetApp()->m_pMainWnd);
CDocument * pDoc = pFrame->GetActiveDocument();
if(NULL != pDoc)
{
    pDoc->SomeFunction();
}

Best Wishes,
-David Delaune

Re: How can I post a user message from a Dialog box to the CDocument class?

Electronic7510-Aug-08 20:11

Electronic75

10-Aug-08 20:11

Thanks a lot David, That solved my current problem but for future and just for knowledge purpose is there anyway to post a message directly to CDocument class from a dialog box I mean is there a way to override default message parsing scheme of MFC and route a message to a specific location?
I read something about message reflection but as far as I understood that's most useful when one wants to propagate a message to child descendants and in my case can't do the trick how about overriding CCmdTaget?

Thanks
Best wishes,

RPC linking error in VC6.0

sunny_vc9-Aug-08 21:16

sunny_vc

9-Aug-08 21:16

Hi,
I am working on an MFC application using VC6.0
Now I have to add an RPC client module in my application.

I am able to generate client and server stubs using MIDL compiler.
Now when I am trying to compile my client application with client stub and
header file,I am getting linker errors like

unresolved external symbol __imp__RpcBindingFree@4
unresolved external symbol __imp__RpcStringFreeA@4
unresolved external symbol __imp__RpcBindingFromStringBindingA@8
unresolved external symbol __imp__RpcStringBindingComposeA@24
unresolved external symbol __imp__NdrFreeBuffer@4
unresolved external symbol __imp__NdrSendReceive@8
unresolved external symbol __imp__NdrConformantStringMarshall@12
unresolved external symbol __imp__NdrGetBuffer@12
unresolved external symbol __imp__NdrConformantStringBufferSize@12
unresolved external symbol __imp__NdrClientInitializeNew@16
unresolved external symbol __imp__RpcRaiseException@4

Do I need to add any library, if So please tell me how to import and link it.

Regards,
Sunil Kumar

Re: RPC linking error in VC6.0

Jijo.Raj9-Aug-08 21:40

Jijo.Raj

9-Aug-08 21:40

Add Rpcrt4.lib to your linker settings.

Regards,
Jijo.

_____________________________________________________

http://weseetips.com[^] Visual C++ tips and tricks. Updated daily.

Re: RPC linking error in VC6.0

sunny_vc10-Aug-08 16:59

sunny_vc

10-Aug-08 16:59

Yeah , Thanks for the reply. I didnt add the RPCRT4.lib file before.
Now I am able to compile it.

Regards,
Sunil Kumar

how to make mfc opengl installer application

yoel good9-Aug-08 18:21

yoel good

9-Aug-08 18:21

i want to improve my question...
how to make application installer from mfc and opengl.
because i use opengl on my mfc....
please anyone... Sigh | :sigh:

Spawning a new frame within a CDialog's OnBnClickedOk() has the effect of making the new frame immediately go behind the main frame

Sternocera9-Aug-08 14:12

Sternocera

9-Aug-08 14:12

Hello,

I have a dialog through which users of my application can get various reports. They select a date from a calender, and click the dialog's OK button. Then, a new frame is spawned with the report. So far, so good. However, because OnOK() is called, the newly spawned frame is immediately placed behind the main frame(window). This is obviously undesirable. How can I close the dialog, but still have the new frame spawn in front of existing main frame? I've tried doing things like calling EndDialog(0), or OnCancel, which would have been acceptable solutions, had they worked Smile | :)

What Should I do?

Thanks,
Sternocera

RegOpenKey error i cant figure out

locoone9-Aug-08 12:56

locoone

9-Aug-08 12:56

HKEY hKey;
CString path;

hKey = HKEY_LOCAL_MACHINE;
err = ERROR_SUCCESS;

m_list.InsertItem(0, "HKEY_LOCAL_MACHINE\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Installer\\UserData\\S-1-5-18\\Products\\109C30587D582624882DD8B8A2B7808B");
path = "SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Installer\\UserData\\S-1-5-18\\Products\\109C30587D582624882DD8B8A2B7808B";

err = RegOpenKeyEx(hKey, path, NULL, KEY_ALL_ACCESS, &hKey);
if (err == ERROR_SUCCESS)
{
    m_list.SetItemText(0, 1, "Found");
    ErrorExit("RegOpenKey0");
}
else
{
    m_list.SetItemText(0, 1, "Not Found"); <--- this is the one i keep getting
    ErrorExit("RegOpenKey1");
}
RegCloseKey(hKey);

that is the code and it keeps returning error 2 system cant find file but i know the path is good i copied the key from regedit i am on vista 64 bit if it makes a differance ill take any help i can get

Re: RegOpenKey error i cant figure out

David Crow9-Aug-08 16:23

David Crow

9-Aug-08 16:23

locoone wrote:
that is the code and it keeps returning error 2 system cant find file...

If the function fails, the return value is a nonzero error code defined in Winerror.h.

"Love people and use things, not love things and use people." - Unknown

"The brick walls are there for a reason...to stop the people who don't want it badly enough." - Randy Pausch

Re: RegOpenKey error i cant figure out [modified]

locoone9-Aug-08 17:05

locoone

9-Aug-08 17:05

that part i know the part i cant figure out is why it cant find it i was in regedit and used the copy key name to get the key path so i know its right out of 24 keys it finds 12 and cant find 12

modified on Saturday, August 9, 2008 11:28 PM

Re: RegOpenKey error i cant figure out

Mark Salsbery10-Aug-08 8:03

Mark Salsbery

10-Aug-08 8:03

Do you get different results if you use KEY_QUERY_VALUE instead of KEY_ALL_ACCESS?

Mark

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

Re: RegOpenKey error i cant figure out

Rob Manderson10-Aug-08 8:26

Rob Manderson

10-Aug-08 8:26

Unicode? If I recall correctly it's possible to have keys that regedit can't display correctly.
Thus, if you copy and paste you're not copying the entire key. I'd write a quick and dirty iteration
over the root key dumping the raw bytes in each key name to make sure you have the entire key.

Rob Manderson

My bloghttp://robmanderson.blogspot.com[^]

Having problems with Templates

BobInNJ9-Aug-08 4:05

BobInNJ

9-Aug-08 4:05

I wrote the following header file. Actually, what I posted is only a subset of
the header file:

#include <assert.h>

using namespace std;

template class {T> class Polynomial {
public:

Polynomial <T>() : order(-1), coeff( 0 )
{
}

Polynomial <T> ( int order, ... );

T eval( T xValue );
Polynomial & Integrate();

void printIt( ostream &out );
friend ostream & operator << ( ostream &out, Polynomial<T> &poly );

private:

int order;
T *coeff; // Note the lower order terms of the polynomail go first. That
// is for the polynomial x^10 - 5 coeff[0] = -5, coeff[10] = 1
// and all the other values of coeff are 0.
};

typedef Polynomial<double> DoublePolynomial;

Now in the file, poly.cpp, I define the member functions for this class. I also
instantiated the class with the statement:

template class Polynomial<double>;

However, this does not instantiate the operator << . Therefore, if in the main
program I write something like:
cout << poly1 << endl;
where poly1 is of type Polynomail<double> I get an error from the linker. I believe that this
is due to the fact that I did not instantiate the operator << which is a friend of the class.
I am hoping that somebody can tell me how to do this.

Thanks
Bob

Re: Having problems with Templates

Graham Shanks9-Aug-08 11:28

Graham Shanks

9-Aug-08 11:28

I've found this C++ Faq[^] helpfull on template linkage errors. I must admit that I usually put all the declarations in the header file myself to avoid the problems. Putting the declaration for operator << in the header file resolves the linker error.

I'm a bit puzzled why you bothered with the friend operator << at all, since you have a public printIt function, which presumably is called by the operator <<. The friend keyword allows the function access to the internals (private and protected) parts of the class, with a printIt method you don't need this.

You could get the same effect by putting a stand alone template function in the header instead, e.g.

template<class T>
ostream & operator << ( ostream &out, Polynomial<T> &poly )
{
  poly.printIt(out);
  return out;
}

Graham

Librarians rule, Ook!

Re: Having problems with Templates

BobInNJ10-Aug-08 5:49

BobInNJ

10-Aug-08 5:49

Graham,

I want to thank you for your response. It has solved my problem. I am not a big fan of using
the operator << to print the results. I feel that this is best done by a member function. Therefore,
I wrote the function printIt. Therefore the operator << just needs to call printIt. I am also not
a big fan of using the keyword friend. I feel that giving non-member functions access to private data
of a class is not a good idea.

Bob

What are the limits of the drawing area in GDI?

g_sandipan9-Aug-08 3:57

g_sandipan

9-Aug-08 3:57

What are the limits of the drawing area in GDI?

I am using MoveTo(x, y), LineTo(x, y) GDI functions to draw multiple line. LineTo fails (returns FALSE) when the y is more than 1073741951 units.

GetLastError() return error code 534 - "Arithmetic result exceeded 32 bit"

So friends, any advice?
Thanks in advanced

Sandip

Re: What are the limits of the drawing area in GDI?

Mark Salsbery9-Aug-08 5:54

Mark Salsbery

9-Aug-08 5:54

Calculations are probably done with 32-bit integers,
so you'll need to keep your coordinates scaled
to prevent the overflow. Pinning down an exact limit
would be difficult unless you know the actual calculations
being done by the system.

Mark

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

Re: What are the limits of the drawing area in GDI?

Randor 10-Aug-08 6:36

Randor

10-Aug-08 6:36

Both GDI and GDI+ are limited to 1073741951 pixel extents on both vertical and horizontal axis.

Best Wishes,
-David Delaune

change the target of a reference

George_George9-Aug-08 2:28

George_George

9-Aug-08 2:28

Hello everyone,

I am shamed to ask this question because I can not figure out after some experiment. I think for reference variable, once it is binded, the target can not be changed.

But why in my following sample, pi can be binded to a and later binded to b without any issues?

int main()
{
	int a = 10;
	int b = 20;
	int& pi = a;
	pi = b;
	
	return 0;
}

thanks in advance,
George

Re: change the target of a reference

Mark Salsbery9-Aug-08 5:57

Mark Salsbery

9-Aug-08 5:57

I don't know what you mean by "binded".

All you are doing is assigning a value to a variable...
You are free to assign any value to a non-const variable,
as many times as you want to.

Mark

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

Re: change the target of a reference

George_George10-Aug-08 14:53

George_George

10-Aug-08 14:53