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How to implement a callback function in MFC or how to enumerate Process in MFC
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Callback functions are implemented in MFC just as they are implemented in Win32: you create your own function that follows the guidelines specified by the documentation (function return value & parameters), then give this function's address (it's name) as a parameter for the routine that starts the enumeration.
The routine will call your function with the appropriate parameters for each object or instance it finds. In the case of process enumeration, these objects/instances are the different processes running in the system.
The PS API offers an alternative way: it fills a specified DWORD array with the process identifiers. See this page[^] for an example.
-Antti Keskinen
----------------------------------------------
The definition of impossible is strictly dependant
on what we think is possible.
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SiddharthAtw wrote:
...how to enumerate Process in MFC
See if Process32First() and Process32Next() help.
A rich person is not the one who has the most, but the one that needs the least.
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i'd like to update an article that i have posted.
Once there was a 'modify this article' link. Now ,it's gone.
How do i update my article?
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You can only update if it has not been edited by an editor. Otherwise, you need to get hte updated HTML and files and send them in to submit@codeproject.com
Roger Allen - Sonork 100.10016
Roger Wright: Remember to buckle up, please, and encourage your friends to do the same. It's not just about saving your life, but saving the quality of life for those you may leave behind...
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Roger Allen wrote:
submit@codeproject.com
Isn't it webmaster@codeproject.com? This link[^] appears to be confusing... 
rechi
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Though not serious, it's most annoying.
I call CTreeCtrl::CreateEx with the WS_POPUP flag specified. (This is why I use CreateEx instead of Create.) Each time there is an assertion failure. When digging into MFC code, one can see the reason. CTreeCtrl::CreateEx is dumbly redirected to CTreeCtrl::Create that does not accept the WS_POPUP flag. If CTreeCtrl::CreateEx called CWnd::CreateEx directy instead then everything would be fine.
Am I right?
And: how to make Microsoft to fix this issue?
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The apparent answer from Microsoft would be: "Why do you need the WS_POPUP flag ?"
The pop-up window style is just used to determine the outlook of the window in which your control resides, and it's behaviour. For the Tree control, this flag is just about useless, as pretty much always a tree control is a child of some other window (main window), making you use the WS_CHILD flag instead.
The only instance when a tree control is not a child is when you create an application that shows ONLY a tree control and nothing else on your application's screen. This, apparently, sounds like a very crazy idea.
If you want to report a bug, try e-mailing Microsoft support and asking them to redirect it to the appropriate people.
-Antti Keskinen
----------------------------------------------
The definition of impossible is strictly dependant
on what we think is possible.
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This tree control is used as a part of a combo box (that is, a hierarchic tree instead of the list). Search for the ComboTree class here: http://codeproject.com/combobox/combotree.asp.
However, there is a new version of ComboTree out there now, so there is no need for the WS_POPUP flag.
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First, I'm not 100% sure that a CTreeCtrl can be WS_POPUP, however I can't find any documentation that says it can't.
I'm assuming you are using VS.NET or later as the VC6 version of CTreeCtrl doesn't look like it has it's own CreateEx, so it must be calling the CWnd::CreateEx
Looking at the source for VS2003, CTreeCtrl has it's own CWnd, and like you said calls Create and then using ModifyStyleEx to add the Ex-styles. As this is the same for all the classes, I'm hard pressed to think this is a bug.
What line does the ASSERT happen?
You can of course, derive a class from CTreeCtrl and create your own CreateEx as the function is declared virtual in the base class.
Michael
But you know when the truth is told,
That you can get what you want or you can just get old,
Your're going to kick off before you even get halfway through.
When will you realise... Vienna waits for you? - "The Stranger," Billy Joel
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First, I'm not 100% sure that a CTreeCtrl can be WS_POPUP, however I can't find any documentation that says it can't.
Neither do I. Anyway, a given piece of code requires it at the moment (see my other comment).
I'm assuming you are using VS.NET or later as the VC6 version of CTreeCtrl doesn't look like it has it's own CreateEx, so it must be calling the CWnd::CreateEx
I tried the stuff with VC6 - it doesn't have a CTreeCtrl::CreateEx, and Create gives assertion failure just as it should. The project is now in VS.NET (MFC 7.0, now 7.1).
What line does the ASSERT happen?
wincore.cpp(732) in MFC 7.0 or wincore.cpp(734) in MFC 7.1.
You can of course, derive a class from CTreeCtrl and create your own CreateEx as the function is declared virtual in the base class.
Well, you're right. Still, I don't feel like writing an own CreateEx as the "official" one in MFC may change later and call other things besides Create and ModifyStyleEx (though I don't think so for the near future).
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Yogurt wrote:
Still, I don't feel like writing an own CreateEx as the "official" one in MFC may change later and call other things besides Create and ModifyStyleEx (though I don't think so for the near future).
You could always create a new window class which acts as a popup window. And then let it host the tree control. That ought to be pretty safe for the future 
--
C'est normal!
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I am currenly looking for a method (efficient) for streaming live images over a network. This image will then be processed further when receieved. Grabbing the images using directshow (or intels opencv) is easy. I have thought of using some codec for compressing the images and somehow send it. Does anyone have a good solution for my problem?
Best
Dan
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hello,
as you know, kernel32.dll is loaded at windows startup and remains in memory until reboot or shutdown. Furthermore every .exe and .dll which is going to be executed uses the kernel32.dll which means that it is loaded into the adresse space of the calling process. So far so good! At the moment a dll is loaded into memory its dllmain function should recieve 3 parameters whereas one of those descripes wheather the dll is attached by a process/thread or detached.
But in my understanding, a system dll which is already loaded (at startup like kernel32.dll), doesn't get a notification if it is loaded or unloaded into/from a process' adresse space because it is already in the memory! Now is that true or false and how can i examine that ?
Thanks in advance!
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It doesn't sound logical
The Kernel32.dll behaves just like any other DLL would. Here is a link to the MSDN site[^] depicting the different reasons for call.
According to the MSDN:
It is safe to call other functions in Kernel32.dll, because this DLL is guaranteed to be loaded in the process address space when the entry-point function is called.
Following this logic, the Kernel32.dll's entry-point function gets called each time it is loaded into the process' address space. For each process that starts, this DLL provides the basic system services. According to the "Virtual Machine" thinking, each process runs seperately, and believes that it is the only process in the system. Thus, each process needs to access basic system services, and they are provided by this DLL.
You can use the Dependency Walker to see what DLL's your executable loads when it is started (that is, what executables it needs in order to start up). You cannot track the usability of Kernel32.dll in the whole process, because it gets loaded into the system core memory area. Tampering with this area easily causes an access violation or a machine-wide crash.
In conclusion: the Kernel32.dll is active in the system code memory area. From there, it gets loaded into the address space of each process that uses it (all Win32 programs). The entry-point function gets called each time.
If you want to test this yourself, create a system-wide service DLL and debug-run it with RunDll32.exe, that loads it into the memory. Now, create a set of new application that load this DLL. Then track it's DllMain-calling sequences by putting a breakpoint there. Not sure if this works though, no guarantees given...
-Antti Keskinen
----------------------------------------------
The definition of impossible is strictly dependant
on what we think is possible.
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Thanks for your help!
Actually i hoped that i am right, but i have expected that! What i try to do is the following:
I have written a patch which injects some code into the kernel32.dll (Win98) which should load a specific .dll evertime the kernel32.dll is loaded. I have switched the original kernel32.dll with a boot disk. To get a little bit more specific: i have changed the adresse of the entry-point function, so it jumps to my code, where a specific dll should be loaded, and then jump back to the "real" entry-point-function!
The strange but funny thing is, that windows98 starts up as if there is no manipulation in its kernel32.dll! I also have changed the code into something that makes no sense to see what happens, and yes, after that i have gotten a beautiful blue screen! The code to load the additional dll within the kernel32.dll is absolutely correct (that's what i think it is)! I don't have an idea why i doesn't load the dll!
Any ideas ?
Thanks in advance!
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With a tool like dependencywalker for example I can see the function exports of a dll. Is it possible to figure out the parameter list of such an export function (certainly not the names, but perhaps the number and the data types) ?
MS
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if the names are decorated (they looks funny)
you may find out the parameterlist. but usualy they are not decorated and you have no chance. 
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Hi All programers,
i need help with macro for my com class that will be working like this :
class ComObject
ComObject.#anything# (...) will be convert as ComObject.Invoke(anything, ...)
or
ComObject->#anything# (...) will be convert as ComObject->Invoke(anything, ...)
i am not master of c++ my know is this :
template <t>
typedef T::##name(...)
(T::Invoke(#name, ....)
can by this working ???
Thanks !!!!
Anthonius
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Hi,
I have an MDI application with views derived from CHtmlView, and my problem is with Undo,Cut, and Copy menu items under the Edit menu, which is always found disabled. Can anyone tell me how can I enable those menu items when a selection is made in the view.
Thanks and Regards
Jugs
"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."
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Handle an ON_UPDATE_COMMAND_UI message for appropriate IDs (ID_EDIT_UNDO etc.)
Robert-Antonio
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Handle each menu item in your CHTMLView derived class like:
[...]
ON_COMMAND(ID_EDIT_CUT, OnEditCut)
ON_COMMAND(ID_EDIT_COPY, OnEditCopy)
ON_COMMAND(ID_EDIT_PASTE, OnEditPaste)
ON_COMMAND(ID_EDIT_SELECTALL, OnEditSelectAll)
[...]
Below is the implementation for each member function:
void CWebView::OnEditCut()
{
ExecWB(OLECMDID_CUT, OLECMDEXECOPT_DONTPROMPTUSER, NULL, NULL);
}
void CWebView::OnEditCopy()
{
ExecWB(OLECMDID_COPY, OLECMDEXECOPT_DONTPROMPTUSER, NULL, NULL);
}
void CWebView::OnEditPaste()
{
ExecWB(OLECMDID_PASTE, OLECMDEXECOPT_DONTPROMPTUSER, NULL, NULL);
}
void CWebView::OnEditSelectAll()
{
ExecWB(OLECMDID_SELECTALL, OLECMDEXECOPT_DONTPROMPTUSER, NULL, NULL);
}
I got this code from an article somewhere, but unfortunately, I can't find where the article is again. Anyway, this should help you out.
Happy Programming!
WWW::CodeProject::BNEACETP
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My application is in VC++ and it needs to notify the user [may be a message box] whenever there is a change in system password.
How can this be achieved? Is there any simple event registered with the system and handled in the application?
I searched on the web and got to know something about password filters and credential managers but those seem to non-trivial. Is there any other way by which my application can get to know the passwprd change?
This is an urgent requirement. If anybody could suggest something, it will be greatly appreciated!
thanx
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Dear friends,
This problem is related to CRichEditCtrl. Actually i want to display my custom font in this control. My font requires right alignment. So i programatically changed the alignment to right as follows:
PARAFORMAT pf;
pf.cbSize = sizeof(PARAFORMAT);
pf.dwMask = PFM_ALIGNMENT;
pf.wAlignment = PFA_RIGHT;
SetParaFormat(pf);
As such everything works fine for me. But my font is displayed correctly if characters are fitted only in a single line of rich Edit Control. In case when my text needs to fit in multiple lines, i am having trouble. As such text is displayed correctly. But "next" line comes on top of existing line and previous line is moved to bottom. How can i change this default behaviour of rich edit control.
Actually my font is arabic font which needs to get typed from right to left (i.e "reverse" of default behaviour). But i am unable to "reverse" the order in which RichEdit inserts characters in new line.
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Is there a way to generate a tone using MCI by using time an amplitude of sinusoidal wave form as its input?
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