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Re: Dummy dialog! Eugene Pustovoyt13-Dec-01 23:35 Eugene Pustovoyt 13-Dec-01 23:35  That is a work of the DDV function. If you don't want have the message, you must fill edit box before close the dialog. Best regards, Eugene Pustovoyt Sonork ID 100.10002:Yaumen Re: Dummy dialog! Nish Nishant13-Dec-01 23:47 Nish Nishant 13-Dec-01 23:47  Override OnOK() and put a zero into the member variable you have associated with the edit box so that DDV wont complain. Nish Sonork ID 100.9786 voidmain www.busterboy.org If you don't find me on CP, I'll be at Bob's HungOut DLL questions 13-Dec-01 19:51 13-Dec-01 19:51  Is there a way to export an entire class in a .def file? I am working on a Unix-based project and there may be a need to port it to NT. I really want to avoid all the non-portable __declspec(dllexport) and all of those macros. Also, could someone tell me how the heap manager works for DLLs? I've heard that all memory allocated from one DLL must be freed by that DLL because it may be using a different heap manager... That seems like a major problem if it's true. How do people develop plugin DLLs if that is the case? Do people provide destroy() methods on every object created by the DLL so that it can delete it? Cheers, Andy Re: DLL questions Nish Nishant13-Dec-01 20:10 Nish Nishant 13-Dec-01 20:10  Hi Andy I cannot provide you a proper answer but sometimes people create their own heap from their DLLs. Thus those DLLs must delete their private heaps. Look up HeapDestroy,HeapCreate Nish Sonork ID 100.9786 voidmain www.busterboy.org If you don't find me on CP, I'll be at Bob's HungOut Re: DLL questions Joaquín M López Muñoz13-Dec-01 23:57 Joaquín M López Muñoz 13-Dec-01 23:57  As far as I know, .DEFs do not provide any means to export a whole C++ class in one fell swoop. The closest you can get is exporting all of the member functions and variables, but this is pretty complicated due to name mangling. This article discusses the issue in greater detail and proposes alternative approaches. As for the DLL heap manager, I'm afraid what you've heard is true: best way to avoid problems is ensuring that all that is allocated in the DLL is freed by the DLL itself (this post of mine explains what the issues with DLL private heaps are). The most usual technique to deal with this problem is to have exported factory methods like create() and their corresponding destroy()s, as you pointed out. An implication of this is that crossed DLL objects should not be created on the stack (i.e. their ctors should be declared protected). If you still want to have classes that work safely across DLL boundaries but yet do not resort to create() methods, there's a solution: define and export new, delete and all ctors (including the copy constructor), and put the corresponding definitions in the .cpp file (so that they are not inlined). This way, all the allocation/deallocation works is ensured to be made inside the DLL. Joaquín M López Muñoz Telefónica, Investigación y Desarrollo Re: DLL questions Nemanja Trifunovic14-Dec-01 5:03 Nemanja Trifunovic 14-Dec-01 5:03  Joaquín M López Muñoz wrote: As for the DLL heap manager, I'm afraid what you've heard is true: best way to avoid problems is ensuring that all that is allocated in the DLL is freed by the DLL itself Not at all. If you use the same version of CRT for the exe and the dll, you are safe. I do this all the time, and it works fine. I vote pro drink Re: DLL questions Joaquín M López Muñoz14-Dec-01 6:12 Joaquín M López Muñoz 14-Dec-01 6:12  Well, my undersading of the situation (I explain it with much more detail here) is that the you're only safe if the CRT used is dynamically linked. Otherwise you end up with two (or more) CRT "instances", and two or more _crtheap private heaps. If I'm not wrong, it should be easy to prove this with a little test program/DLL combination producing a crash with statically linked CRTs. Joaquín M López Muñoz Telefónica, Investigación y Desarrollo Re: DLL questions Nemanja Trifunovic14-Dec-01 6:37 Nemanja Trifunovic 14-Dec-01 6:37  Oh, I didn't look at your link. Sorry. It is true that I always use dynamically linked CRT. That's why I never had any trouble. I vote pro drink Re: DLL questions pba_14-Dec-01 6:40 pba_ 14-Dec-01 6:40  If you want your code to be portable take a look at how COM works. Define a creator function for your objects, and each object should manage his own life. So you don't care about heap managers, name mangling , etc, and as long as you stick with the C++ standard, your code will be portable. Re: DLL questions Philip Patrick14-Dec-01 14:33 Philip Patrick 14-Dec-01 14:33  Well, providing destroy() works well. And this is true that memory allocated in DLL must be freed in DLL. But when you created a new VC++ project, you can look in its properties, C/C++ tab, Code genertion and you will see "Debug multithreaded DLL" option selected which is by default. With this option you can use your memory as you wish (I mean in case of DLLs). Exporting classes throw .def file is not allowed as I know. How people making plugins? Simple. There are many different ways. Fisrt to have only raw global functions. But if you want to use class, write an abstract class (which is need only header file) and derive your plugin's class from it. Now provide global function in your DLL like "GetPlugin()", returning the pointer to the abstract class and call it from your application. This way you "exported" a class from DLL And this way I did some time ago But of course, not so simple. My suggestion is to open MSDN and read about DLLs, there are many information about it Philip Patrick Disabling buttons Cam13-Dec-01 16:21 Cam 13-Dec-01 16:21  How do I disable a pushbutton in a dialog?? I've been round-and-round through MSDN. It can't really be that hard, can it?? ~Cam Desautels (BinaryUprising.com) Re: Disabling buttons Michael Dunn13-Dec-01 16:25 Michael Dunn 13-Dec-01 16:25  EnableWindow ( hwndControl, FALSE ); --Mike-- http://home.inreach.com/mdunn/ "Not our fault we are intellectually superior to the rest of the office." -- Paul Watson in the Lounge, 12/12/2001 Sonork - 100.10414 AcidHelm Re: Disabling buttons Nish Nishant13-Dec-01 18:06 Nish Nishant 13-Dec-01 18:06  or from MFC:- CWnd::EnableWindow (false/true) Nish Sonork ID 100.9786 voidmain www.busterboy.org If you don't find me on CP, I'll be at Bob's HungOut Re: Disabling buttons Cam13-Dec-01 18:36 Cam 13-Dec-01 18:36  Oh, thank you, guys. It had to be simple. ~Cam Desautels (BinaryUprising.com) Getting a pointer to the view object Cam13-Dec-01 15:12 Cam 13-Dec-01 15:12  Can someone tell me if there is a function to get a pointer to the view object? For example, you can get one to the document object like so: CMyAppDoc *pDoc = GetDocument(); Why can't there be a bloody 'GetView()' function?? ~Cam Desautels (BinaryUprising.com) Re: Getting a pointer to the view object Rick York13-Dec-01 15:35 Rick York 13-Dec-01 15:35  There are several ways to do this. From what level do you want to get it (app, doc, mainframe, etc.) ? Re: Getting a pointer to the view object Cam13-Dec-01 15:52 Cam 13-Dec-01 15:52  I guess from the doc level. ~Cam Desautels (BinaryUprising.com) Re: Getting a pointer to the view object Ravi Bhavnani13-Dec-01 17:05 Ravi Bhavnani 13-Dec-01 17:05  See CDocument::GetFirstViewPosition() and CDocument::GetNextView(). /ravi "There is always one more bug..." http://www.ravib.com ravib@ravib.com Re: Getting a pointer to the view object Eugene Pustovoyt13-Dec-01 23:48 Eugene Pustovoyt 13-Dec-01 23:48  Hello, This question is in detail considered in article Q108587 HOWTO: Get Current CDocument or CView from Anywhere Microsoft Knowledge Base! Best regards, Eugene Pustovoyt Sonork ID 100.10002:Yaumen Help me create .inf file in win2000!! Jerry Hu13-Dec-01 14:30 Jerry Hu 13-Dec-01 14:30  Hi, I have developed a TDI filter driver(build in *.sys) in Win2000,but i haven't got the .inf file,so it is no use and it's urgent to use it for me... please help me!!! Thanks a lot for all replies Re: Help me create .inf file in win2000!! Nish Nishant13-Dec-01 18:15 Nish Nishant 13-Dec-01 18:15  If you wrote a device driver, I guess you should write your inf for it too huh? Nish p.s. You are asking like, "I can multiply 34567835 with 358454, but can someone tell me how to multiply 5 with 8" Sonork ID 100.9786 voidmain www.busterboy.org If you don't find me on CP, I'll be at Bob's HungOut CDataGrid in C++ 13-Dec-01 12:08 13-Dec-01 12:08  HI, I am using DataGrid control in my MFC app. One of the requirements is to loop through each selected record, pick the third column value and update the database if any item has changed. Surprisingly most of the samples listed in MSDN show the VB examples. I am interested in a C++ sample that manipulates the selected rows, gets count of # of selected rows, etc. Can anyone point me to an in-depth usage of DataGrid Sample code. Also there are lot of LPDISPATCH routines like "LPDISPATCH GetSelBookmarks()" that can further call more functions. However I have no clue of what interface they support. Nagendra Re: CDataGrid in C++ 14-Dec-01 0:50 14-Dec-01 0:50  see sample (using ADO) http://www.codeproject.com/useritems/msdatagrid.asp or (OLE DB) http://www.codeproject.com/useritems/msdatagridoledb.asp Stupid Compiler Tricks Cam13-Dec-01 11:51 Cam 13-Dec-01 11:51  File this one under stupid compiler tricks: (there's apparently no html allowed...) http://www.BinaryUprising.com/images/StupidError.JPG rriiiiight..... ~Cam Desautels Re: Stupid Compiler Tricks 13-Dec-01 12:33 13-Dec-01 12:33  And I thought "I" had frustrating error messages! Why did that happen, do ya know?

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