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i'm not sure, but rrdtool can also just make a .gif
i think that's the way it works
make gif and use php to show it the user of a website
so you could use it the same way, just show the gif
hmm
i think it works like that 
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hi, i am aware how to take the address of a function, but what about a bound member function? The compiler won't let me do this.
here is my code, i try to pass a function pointer to a child class to notify the parent of events:
class1.h
class class1 {<br />
public: class1(int (*)(int, int, int, int));<br />
};
class1.cpp
#include "class1.h"<br />
class1::class1(int (*notifyFunc)(int, int, int, int)) {}
class2.h
#include "class1.h"<br />
<br />
class class2 {<br />
private:<br />
class1 *client;<br />
int TheNotifyFunc(int, int, int, int);<br />
public:<br />
class2();<br />
};
class2.cpp
#include "class2.h"<br />
<br />
class2::class2() {<br />
client = new class1(this->TheNotifyFunc);
}<br />
<br />
int class2::TheNotifyFunc(int, int, int, int) {<br />
return 0;<br />
}
main.cpp
#include "class2.h"<br />
<br />
void main() {<br />
new class2();<br />
}
my compiler error is:
Compiling...<br />
class2.cpp<br />
class2.cpp(4) : error C2664: 'class1::class1(int (__cdecl *)(int,int,int,int))' : cannot convert parameter 1 from 'int (int,int,int,int)' to 'int (__cdecl *)(int,int,int,int)'<br />
None of the functions with this name in scope match the target type
any workarounds?
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I don't think the way you are trying to do it will work anyway...
Why do you want to pass "a bound member function" in the first place? Presumably because you want/need that function to access some data of a particular instance of class2, isn't it? Non static class member functions include an implicit first parameter named this, which is a pointer to the particular instance for which the method is invoked. So int TheNotifyFunc(int, int, int, int) is actually int TheNotifyFunc(class2* this, int, int, int, int);, although the language hides that detail. Then, how do you intend to pass the this parameter from class1 when you need to invoke the function?
If you don't actually need to access instance data in TheNotifyFunc(), then you should declare it as static.
If you do need to access instance data, you could, at first, program something like this:
#pragma once
class Parent;
class Child
{
private:
Parent* m_pParent;
public:
Child(Parent* pParent)
void SomeChildFunction();
};
#include "child.h"
#include "parent.h"
Child::Child(Parent* pParent)
: m_pParent(pParent)
{
}
void Child::SomeChildFunction()
{
if (m_pParent)
m_pParent->OnChildEvent(n1, n2, n3, n4);
}
#pragma once
class Child;
class Parent
{
private:
Child* m_pChild;
public:
Parent();
~Parent();
int OnChildEvent(int n1, int n2, int n3, int n4);
};
#include "parent.h"
#include "child.h"
Parent::Parent()
{
m_pChild = new Child(this);
}
Parent::~Parent()
{
delete m_pChild;
}
int Parent::OnChildEvent(int n1, int n2, int n3, int n4)
{
}
However, the fact that you were trying to use generic notifier functions rather than plain old object pointers and method calls, makes me think this approach might not be appropriate in your case. Indeed, what if you need your Child objects to have parents of different non related classes? In other words, what if you don't want your Child class to be tied (coupled) to a particular Parent class? That is, the only thing your Child class needs to know about (and depend on) from its "parent", is a way to send it some specific notification.
If that is the case, I humbly suggest you read this article[^], and then program something like this:
#pragma once
#include "cppinterfaces.h"
DeclareInterface(IChildEventTarget)
virtual int OnChildEvent(int n1, int n2, int n3, int n4) = 0;
EndInterface(IChildEventTarget)
#pragma once
interface IChildEventTarget;
class Child
{
private:
IChildEventTarget* m_pEventTarget;
public:
Child(IChildEventTarget* pEventTarget)
void SomeChildFunction();
};
#include "child.h"
#include "IChildEventTarget.h"
Child::Child(IChildEventTarget* pEventTarget)
: m_pEventTarget(pEventTarget)
{
}
void Child::SomeChildFunction()
{
if (m_pEventTarget)
m_pEventTarget->OnChildEvent(n1, n2, n3, n4);
}
#pragma once
#include "IChildEventTarget.h"
class Child;
class Parent : implements IChildEventTarget.h
{
private:
Child* m_pChild;
public:
Parent();
~Parent();
int OnChildEvent(int n1, int n2, int n3, int n4);
};
This is a much cleaner design, because your Child does not depend anymore in any specific "parent" implementation, which is what I think you was looking for with the generic function pointer. The child class does not need to be modified (not even recompiled) because of irrelevant changes in the parent class, and any other unrelated class can act as a parent as long as it implements the IChildEventTarget interface.
I've found this interface approach very useful in many cases, not just for events and event targets. However, for this specific case, you should also take a look at this excellent article[^] by Don Clugston[^].
Hope that helps,
--
jlr
http://jlamas.blogspot.com/[^]
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i read the articles, but i dont think they apply to me. my goal is to pass the member function pointer to a win32 WNDPROC.
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The usual approach in these cases is to pass a global function or a static member function, eventually registering the callback along with a user data value, that gets passed back as a parameter in each callback. As the user data value, you may pass a pointer to some object, and the static class member can use it to access other non static members of the class.
--
jlr
http://jlamas.blogspot.com/[^]
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Recently I have read some materials on RTP ,But I still could not know how to realize it ? Can anybody tell me some advice .
I have known the RTP/RTCP packet structure ,but I don't know how to fill the structure ,for I wonder how to get the original data used to fill in the stucture ,which I guessed is realized by myself not the RTP protocol.
AntonlioX
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HELP...!!!
Can any one show me the interface of Gina in XP??
I define my own MyGina.dll in XP and replace System's gina.dll ,but when i login,it meet bluescreen error ??what's wrong with this?? it works correctly in 2000 and 2000/server,
is there any more interface in Xp than in 2000?what are they??
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Gee, maybe if you cross-post to just one more irrelevant forum someone will anwer your question. Might I recommend the suggestions forum?
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I'm looking for any C++ developers interested in testing a new XML library focusing on a simplistic public interface. Developers of almost any skill are welcome to submit a request. Either e-mail me directly or leave a message along with your e-mail address in this topic. A lot of people have expressed a great interest in the project, and I along with them, believe it'll create a massive impact in the world of Open Source.
Just send the e-mails to skonen@gmail.com . Anybody who is interested in giving it a try needs to be proficient in English and have no fear with expressing their opinions.
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I may be interested. Can you post the link to the site?
/ravi
My new year's resolution: 2048 x 1536
Home | Articles | Freeware | Music
ravib@ravib.com
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Currently I do not have an informational website up and running. Though I have registered a project account with SourceForge it doesn't have much for indepth details. However, the XML library has complete documentation including overviews and examples.
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Stuart Konen wrote:
the XML library has complete documentation including overviews and examples.
That nice, Your XML Library have complete documentation, but I would love to check it for Speed and Size  , before using in my projects
"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow
cheers,
Alok Gupta
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![Rose | [Rose]](https://www.codeproject.com/script/Forums/Images/rose.gif) Suppose I have an MDI project.
The wizard automatically placed my document object implementation file with:
IMPLEMENT_DYNCREATE(CCatchbugDoc, CDocument)
If I wish to have my document object to have multiple inheritance (CDocument and another non-CObject object, which is created by hand), do I need to add any new stuff under
IMPLEMENT_DYNCREATE macro?
Thanks
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IMPLEMENT_DYNCREATE does not work with multiple inheritance.
John
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yccheok wrote:
If I wish to have my document object to have multiple inheritance (CDocument and another non-CObject object, which is created by hand), do I need to add any new stuff under
IMPLEMENT_DYNCREATE macro?
No, it isn't neither needed nor possible. MFC's macros and functions that deal with runtime type are designed with single inheritance in mind. However, you can make use of multiple inheritance as long as you:
- Observe the usual cautions regarding multiple inheritance in general (i.e.: take care of multiple use of the same base class, etc.), and
- Declare what MFC expects as the
first base class (i.e.: CDocument in this case), so that things like pCatchbugDoc->IsKindOf(RUNTIME_CLASS(CDocument)) and CDocument* pDoc = (CDocument*) pCatchbugDoc keep working.
--
jlr
http://jlamas.blogspot.com/[^]
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Hi everybody!
I want Create and develop a windows service in Visual Studio.Net( Visual C++ )
and I want use the MFC instructions in this.
if is it possible please help me!
Tell me what shulde I do?
Please answer to me immediately!
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BiNam wrote:
Please answer to me immediately!
I hope you don't mind my delay, Sir. My humble apologies for not answering faster, as you demanded and surely deserve. 
BiNam wrote:
I want Create and develop a windows service in Visual Studio.Net( Visual C++ )
and I want use the MFC instructions in this.
First, you should check What MFC Cannot Do for You[^], and in particular the part where it specifically says:
Microsoft does not support using MFC to build Windows services
--
"slow" jlr
http://jlamas.blogspot.com/[^]
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Hello Jose Lamas Rios!
Thanks a lot for your useful help!
How one program requests from a service?
Please explain to me completely.
Thank you!
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Generally you are supposed to figure stuff out for yourself and ask here for help on specific issues. Not "How do I write a xxx type of program?".
Go away and do some studying. Work out the basics and then come back and ask details. There are plenty of excellent examples of writing services here on CP.
HTH.
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Jose Lamas Rios wrote:
My humble apologies for not answering faster, as you demanded and surely deserve.
Jose Lamas Rios wrote:
Microsoft does not support using MFC to build Windows services
Yeap, But Mr. Naughter this article support MFC in Window Service too:-
http://www.codeproject.com/system/cntservice.asp[^]
"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow
cheers,
Alok Gupta
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Thanks Ravi for your help
But if you can,give me a sample code for create a Windows Service in MFC
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Is the sample in the article not sufficient? 
/ravi
My new year's resolution: 2048 x 1536
Home | Articles | Freeware | Music
ravib@ravib.com
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Hello,
I have this code!
HWND hwndTextBox = NULL;
hwndTextBox = GetDlgItem(hwndDlg,IDC_EDIT1);
if(CDesktop::None != (CDesktop::ShowStatus)iIndex)
{
if(GetWindowText(hwndTextBox,text,MAX))
bSuccess=g_objDesktop.SetDesktopWallpaper (text,CDesktop::ShowStatus)iIndex);
}
But now I want to use it in a dialog (MFC) and I dont now how to get the text as a char enter in the EDIT1
as it supose to do. Is there anyone that can help me?
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