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Re: About RUNTIME_CLASS Tom Archer19-Jul-03 17:35 Tom Archer 19-Jul-03 17:35  RUNTIME_CLASS is a macro that returns the static CRuntimeClass member data for a given class which allows the function being called (the CSingleDocTemplate c'tor in this case) to validate RTCI (Run-Time Class Information). To be more specific, the CSingleDocTemplate needs to verify that a CDocument-derived class, a CFrameWnd-derived class and a CView-derived class are all being sent. As a result, this macro is used in passing those values. Cheers, Tom Archer Inside C#, Extending MFC Applications with the .NET Framework It's better to listen to others than to speak, because I already know what I'm going to say anyway. - friend of Jörgen Sigvardsson Re: About RUNTIME_CLASS FlyingDancer19-Jul-03 18:56 FlyingDancer 19-Jul-03 18:56  Thank you! When to use Critical Sections in Threads? Aidman19-Jul-03 12:00 Aidman 19-Jul-03 12:00  Hi, all When is it necessary to use critical sections in a multithread application? I have read that it should be used when “manipulating shared resources”, but what do those that really mean? Does it mean when manipulating: global variables, allocated memory chunks or files? And does “manipulating” mean: reading (probably not), writing or reallocating? Could anyone please demonstrate some code examples for typical situations when critical sections should be used? Thanks in Advance Aidman » over and out We haven't inherited Earth from our parents, instead we have borrowed her from our children; an old Indian saying. Re: When to use Critical Sections in Threads? Rickard Andersson2019-Jul-03 12:35 Rickard Andersson20 19-Jul-03 12:35  Use it when you assign global varibles, reading is safe. Allocated memory chunks and files, don't know. Rickard Andersson Here is my card, contact me later! UIN: 50302279 E-Mail: nikado@pc.nu Interests: C++, ADO, SQL, Winsock, 0s and 1s Re: When to use Critical Sections in Threads? peterchen19-Jul-03 23:00 peterchen 19-Jul-03 23:00  Rickard Andersson18 wrote: reading is safe. not really, when it's not an atomic operation - anything above size of 4 is in danger: you might catch the first half before the modification, and the other afterwards. "Der Geist des Kriegers ist erwacht / Ich hab die Macht" StS sighist | Agile Programming | doxygen Re: When to use Critical Sections in Threads? Rickard Andersson2020-Jul-03 0:43 Rickard Andersson20 20-Jul-03 0:43  Oh, okay! I've learned it from CP when I one time also talked about critical sections and threads etc here. Rickard Andersson Here is my card, contact me later! UIN: 50302279 E-Mail: nikado@pc.nu Interests: C++, ADO, SQL, Winsock, 0s and 1s Re: When to use Critical Sections in Threads? Ted Ferenc19-Jul-03 12:58 Ted Ferenc 19-Jul-03 12:58  The best advise I saw was if you think you need a critcal section then you probably do, err on the side of caution. Manipulating, IMHO, means changing a shared resource, if a file is open for reading only by all threads then you don't need it, but if one thread writes to the file, then you probably do. Having a global variable is not a good idea at the best of times, but especially not in a multi threaded application. I would recomend the book "Multithreading applications in Win32" by Jim Beveridge and Rober Wiener. If I have seen further it is by standing on the shoulders of Giants. - Isaac Newton 1676 Re: When to use Critical Sections in Threads? Neville Franks19-Jul-03 13:03 Neville Franks 19-Jul-03 13:03  Whenever > 1 thread needs read or write access to a resource (memory/disk/database record whatever) you typically need to synchronize the access. Depending on the resource it may be possible for > 1 thread to have simultaneous read access, but there may be a bigger picture issue such as one thread writing to the resource when others are reading it. You then need to go a level higher and see whether transactions are needed etc. Bottom line is you need to go read a good book or two on multithreaded design and implementation and all that entails. Multithreading is a whole world unto itself where deadlocks occur at the blink of an eye. And debuging multithreaded apps is way harder than single threaded apps. Neville Franks, Author of ED for Windows. Free Trial at www.getsoft.com Re: When to use Critical Sections in Threads? Ryan_Roberts19-Jul-03 13:18 Ryan_Roberts 19-Jul-03 13:18  You should guard all non constant data that you share between threads with some sort of locking mechanism. 'Manipulating' in this context, probably does mean writing. A critical section is a spin lock, it uses an atomic instruction to repeatedly test for and aquire the lock. This makes critical sections unsuitable for locking resources that may take a long time to become free, the other threads will consume cycles waiting for the lock. You should use a kernel lock in these cases, such as a mutex or event. Critical sections are only suitable for syncronising threads, not processes - they rely on shared memory. Have a look at the boost thread library http://www.boost.org/libs/thread/doc/[^], it makes it a hell of a lot easier to write correct multithreaded programs. Ryan. Re: When to use Critical Sections in Threads? Aidman19-Jul-03 14:13 Aidman 19-Jul-03 14:13  Thanks mates I am beginning to realize the many disadvantages of using multithreads. It’s not as “perfect” as I imagined, but then again nothing ever is Aidman » over and out We haven't inherited Earth from our parents, instead we have borrowed her from our children; an old Indian saying. Saving progress in ListCtrl? spaced_out19-Jul-03 10:19 spaced_out 19-Jul-03 10:19  There are several options out there such as drag and drop where you can change the order of a list control. So, when the user modifies your list control, How do you save changes made to a ListCtrl by a user? (so that those changes could be loaded in at a later time) Any suggestions would be helpful. I wish I could type better ... Re: Saving progress in ListCtrl? Tom Archer19-Jul-03 11:48 Tom Archer 19-Jul-03 11:48  I'm not sure I follow the question. The ListCtrl (SysListView32) itself doesn't do anything magic to save its state or contents. You're responsible for doing that. Having said that, the ways in which you can persist the order of your list control's contents are way too numerous to get into without more specifics on what you're trying to do. Cheers, Tom Archer Inside C#, Extending MFC Applications with the .NET Framework It's better to listen to others than to speak, because I already know what I'm going to say anyway. - friend of Jörgen Sigvardsson Re: Saving progress in ListCtrl? wb19-Jul-03 21:16 wb 19-Jul-03 21:16  create your own ListControl Class and when the destructor is called, store all the info about the control somewhere. the registry?! I use a .mdb file and some SQL, so I can change the ListCtrl "on the fly" Re: Saving progress in ListCtrl? Michael P Butler20-Jul-03 4:32 Michael P Butler 20-Jul-03 4:32  I maintain an array of the column details that I write out to the registry for later reloading. Michael 'War is at best barbarism...Its glory is all moonshine. It is only those who have neither fired a shot nor heard the shrieks and groans of the wounded who cry aloud for blood, more vengeance, more desolation. War is hell.' - General William Sherman, 1879 How to display "Properties" system dialog for multiple files? s_k19-Jul-03 9:48 s_k 19-Jul-03 9:48  Hi, how can I display system "Properties" dialog for more than one file/directory? Like in Explorer when I have selected multiple files/directories, I click right button and from context menu a select "Properties". Now I use this code: SHELLEXECUTEINFO sei; ZeroMemory(&sei, sizeof(sei)); sei.cbSize = sizeof(sei); sei.hwnd = AfxGetMainWnd()->GetSafeHwnd(); sei.nShow = SW_SHOW; sei.lpFile = filePath; sei.lpVerb = _T("properties"); sei.fMask = SEE_MASK_INVOKEIDLIST; ShellExecuteEx(&sei) It works fine for single file/directory. But how can I display that dialog for more than one file/directory? Thanks in advance. Re: How to display "Properties" system dialog for multiple files? s_k26-Jul-03 1:36 s_k 26-Jul-03 1:36  Now I trid to put NULL char between file paths and double NULL at the end of list, but it also doesn't work... Dynamic set of QuickInfo Kristian Kratzenstein19-Jul-03 8:51 Kristian Kratzenstein 19-Jul-03 8:51  Has anyone a exmple, to set the Quickinfo for the Statusbar dynamic during the runtime ? I need this, cause the language of the prog could be changed during runtime too, and this is the only problem. Also to change the font. SetFont set not the Font I want, but some internal systemfont. Thanks in advance Kristian PS : I use mfc 7.0 Tooltip messages for CPropertySheet haritadala19-Jul-03 8:50 haritadala 19-Jul-03 8:50  Hello all I would like to display tooltip help messages whenever user drag & drop (?)Help on a particular control of the property page. If you any knows how to do it, please help me. Thanks for your help. Hari. Re: Tooltip messages for CPropertySheet John R. Shaw20-Jul-03 11:52 John R. Shaw 20-Jul-03 11:52  I personaly do not know. I recommend you search for "tooltips" here at codeproject (or codeguru.com), since there are several articles on the subject that may help you figure out how to accompish your goal. INTP Dialog Boxes in Classes Zak_19-Jul-03 8:36 Zak_ 19-Jul-03 8:36  Hi, I had my little program running a dialog box with the callback function running perfectly. The definition of the callback function was as follows - INT_PTR CALLBACK DlgDeviceProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam); And I called it from the main program as follows - DlgDevicehWnd = DialogBox(hInstance, MAKEINTRESOURCE(IDD_DIALOG1), hWnd, DlgDeviceProc); I have now decided to make all of the dialog box related items into a class to clear things up. However it appears to have created a few problems for me. The class style definition and call follow respectively (the class is called CDeviceSetup, and the instance used is DeviceSetup) - INT_PTR CALLBACK CDeviceSetup::DlgDeviceProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam); DlgDevicehWnd = DialogBox(hInstance, MAKEINTRESOURCE(IDD_DIALOG1), hWnd, DeviceSetup.DlgDeviceProc); With this setup I now get the following compilation error on the call line - d:\projects\newdialog\dlgdevice.h(449) : error C2664: 'DialogBoxParamA' : cannot convert parameter 4 from 'int (struct HWND__ *,unsigned int,unsigned int,long)' to 'int (__stdcall *)(struct HWND__ *,unsigned int,unsigned int,long)' Now the CALLBACK (which refers back to _stdcall) is still present but it VC++ seems to think not. Does anybody have any ideas? Thanks in advance Zak Re: Dialog Boxes in Classes John R. Shaw19-Jul-03 9:26 John R. Shaw 19-Jul-03 9:26  Try making the callback function static: static INT_PTR CALLBACK CDeviceSetup::DlgDeviceProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam); Or it will never work. INTP Re: Dialog Boxes in Classes Bob Stanneveld20-Jul-03 7:21 Bob Stanneveld 20-Jul-03 7:21  The reason why it is not possible to make CALLBACK memberfunctions is because a 'hidden' parameter is passed to the member function. It is the 'this pointer'. A CALLBACK function is not called by any object, so no this pointer is availeble! Solution: you can make a Callback function and call the member function from there. Arrays of buttons on a dialogue box Trollslayer19-Jul-03 6:28 Trollslayer 19-Jul-03 6:28  I want to have an array of buttons I can access as an array within the program, e.g. Button[3]->GetCheckState(). It is possible by creating individual member variables and assigning an array of pointers to these or creating the whole array within code. Does anyone have a more elegant suggestion ? Thanks. Elaine The tigress is here Found an article that does it Trollslayer19-Jul-03 6:41 Trollslayer 19-Jul-03 6:41  http://www.codeproject.com/buttonctrl/custombuttons.asp#xx51685xx[^] Elaine The tigress is here Re: Arrays of buttons on a dialogue box Ryan Binns19-Jul-03 20:03 Ryan Binns 19-Jul-03 20:03  Trollslayer wrote: It is possible by creating individual member variables and assigning an array of pointers to these or creating the whole array within code. Absolutely When you add button objects to your dialog, add them using ClassWizard as normal, and then replace the individual buttons with an array. Instead of CButton m_Button1; CButton m_Button2; Use CButton m_Buttons[2]; And then in the DoDataExchange() function, replace DDX_Control(IDC_BUTTON1, m_Button1); DDX_Control(IDC_BUTTON2, m_Button2); with DDX_Control(IDC_BUTTON1, m_Buttons[0]); DDX_Control(IDC_BUTTON2, m_Buttons[1]); Works beautifully Ryan "Punctuality is only a virtue for those who aren't smart enough to think of good excuses for being late" John Nichol "Point Of Impact"

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