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Hi.
You have to create your own CEditEX class, (in example) derivated from CEdit. So then, you will be able to override some messages and use CEdit methods like SetSel() and so on.
Make a search about "windows subclassing" here in CP and you will find a lot of articles.
Kind regards.
Demian.
"I have always wished that my computer would be as easy to use as my
telephone. My wish has come true. I no longer know how to use my telephone."
-Bjarne Stroustrup, computer science professor, designer of C++
programming language (1950- )
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I have to think about a development involving mobil phones and security cameras.
The fact is, someone could check a security camera from his cell phone anywhere.
What I need it's just something to read, maybe someone of you had seen an article about that before.
I thought in JAVA for cell phone software client and in C++, (or C#) for server side application that receive the incomming connection from phones.
I really appreciate any suggestion.
Thank you very much.
Cheers.
Demian.
"I have always wished that my computer would be as easy to use as my
telephone. My wish has come true. I no longer know how to use my telephone."
-Bjarne Stroustrup, computer science professor, designer of C++
programming language (1950- )
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Hello all,
I am having two exe's and i am calling one exe from another exe using ShellExecute() function. My problem is i want to pass some variable values from one exe to another. How can i do this??
Thanks in advance
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neha.agarwal27 wrote: How can i do this??
As commandline...
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Hi.
You could use the Windows registry.
Cheers.
Demian.
"I have always wished that my computer would be as easy to use as my
telephone. My wish has come true. I no longer know how to use my telephone."
-Bjarne Stroustrup, computer science professor, designer of C++
programming language (1950- )
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Demian Panello wrote: You could use the Windows registry.
good software design should not include registry as active place for data share between two application
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neha.agarwal27 wrote: My problem is i want to pass some variable values from one exe to another
when spawning the 2nd program, or during its execution ?
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Hi,
1. If variable is required before starting another exe then pass that variable as command line.
2. If you want to pass variable after starting another exe then use Inter Process Communication such as WM_COPYDATA, Pipes and Shared Memory.
Amar
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Amar Sutar wrote: WM_COPYDATA, Pipes and Shared Memory.
they are one of best IPC mechanism, but i recommend you discourage use of PIPe.. Window message is also good option
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Hello everyone,
I am learning the storage area of Windows memory, but I am not sure what is the usage for Free Store area, what is the differences between Free Store area and heap area?
http://www.gotw.ca/gotw/009.htm
--------------------
Free Store The free store is one of the two dynamic memory
areas, allocated/freed by new/delete. Object
lifetime can be less than the time the storage
is allocated; that is, free store objects can
have memory allocated without being immediately
initialized, and can be destroyed without the
memory being immediately deallocated. During
the period when the storage is allocated but
outside the object's lifetime, the storage may
be accessed and manipulated through a void* but
none of the proto-object's nonstatic members or
member functions may be accessed, have their
addresses taken, or be otherwise manipulated.
--------------------
Could anyone provide more information or sample please?
thanks in advance,
George
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George_George wrote: what is the differences between Free Store area and heap
For all practical purposes, it is the same thing.
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Thanks for your clarification Nemanja!
regards,
George
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Hi!
I have an app that uses Crystal Reports for reports. Some functions cannot be easily realised in crystal, so I thought about calling my main app for that work.
Now, I can add custom fn's to Crystal, by writing a U25 DLL. The idea I tested was to have a function in this DLL that gets called from my main app and there deposits, in shared storage, the addresses I need to call to get my data. When the DLL gets loaded from Crystal, then it calls my app through those pointers.
I have tested it and it works, but I have been told in is a bad idea.
Suggestions?
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As a general rule this sort of thing is considered unsafe and using Sockets or COM IPC from your Dll would be preferred as more robust and flexible than rolling your own solution in shared memory. I have used COM Connection Points in the past to communicate between a Dll loaded into the Microsoft Management Console and an external process. Not easy but it worked and was pleasingly fast.
Nothing is exactly what it seems but everything with seems can be unpicked.
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OK. Not sure what to do at this point. Implementing COM for this seems an awful lot of work for such a simple task. Any good pointers where to get started?
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That's going to depend a lot on what you know and what your requirements are.
On one hand if it works leave it be. On the other it does sound like a temporary solution so perhaps try some separate experiments with COM, ATL makes this easy, to see if you can find a replacement architecture that you're happy with.
If you want to avoid COM give Socket comms a try, there's loads of examples available. This has the added advantage that you can transparently run your application on the same or a separate machine. Either way CP is probably going to be the best place to find examples. If you've managed to write your own shared memory exchange system that works you'll have nothing to fear from either of these approaches and probably don't need advice from me.
Nothing is exactly what it seems but everything with seems can be unpicked.
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Well, it is a commercial app, so I'd rather not do anything dangerous  I have been banging my head against the limitations of Crystal Reports for the last 10 years And we do some pretty cool stuff, manipulating the innards of the reports ar runtime, using the CR apis. The New CR apis are all COM anyway so I had to learn those.
I found a good, two-part article on COM here and I am currently reading it. It might be that implementing a small COM server in my app might be worth the peace of mind here.
App and report will always be on the same machine so.. Also, COM feels quite logical as it is just a (synchronous) function call.
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It is better that the dll has its own data, and the dll makes it own copies of the data. Preprocess the data in the App and THAN call the dll to finish the job.
Try to develop a data model which is clearly structered!! A clear structure helps you to develop good code and debug it easy.
Ask a friend/colegue for a half hour to discuss it. This is really worth it.
Greetings from Germany
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I am discussing it, here
Problem is that there are aspects of the data model that I cannot control since I do not have access to the Crystal Reports sources. The crystal reports viewer is for all intents and purposes a black box. Only way to extend it is to create a custom DLL that gets registered with Crystal and called at runtime.
So, preprocessing in the app is really what I do, let me elaborate. The functions I need are along the lines of "workdays", input in the report is two dates. The result is not just a range, but it must take into account the employee-specific calendar.
Alternatively could I duplicate this logic in the DLL, but then again would I have to have a separate Db connection (with a separate login) for the report.
So when I call "Arbetsdagar(date,date) from within my crystal report definition, crystal calls the DLL and it is just a wrapper that calls the real function in the app.
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Hi
I'm facing some problem in standard MFC application. In my application, I'm able to run only 3 instances of my application simultaneously.That is, I'm able to open only three login screens at the same time, but I dont want this limitaton. I'm currently working in Windows XP. However, when I ran my application in Windows NT, only 4 instances can ber run at a time. When I tried to open it fourth time in Windows XP, it gets crashed at the following line of code.
//winfrm.cpp
BOOL CFrameWnd::Create(LPCTSTR lpszClassName,
LPCTSTR lpszWindowName,
DWORD dwStyle,
const RECT& rect,
CWnd* pParentWnd,
LPCTSTR lpszMenuName,
DWORD dwExStyle,
CCreateContext* pContext)
{
HMENU hMenu = NULL;
if (lpszMenuName != NULL)
{
// load in a menu that will get destroyed when window gets destroyed
HINSTANCE hInst = AfxFindResourceHandle(lpszMenuName, RT_MENU);
if ((hMenu = ::LoadMenu(hInst, lpszMenuName)) == NULL)
{
TRACE(traceAppMsg, 0, "Warning: failed to load menu for CFrameWnd.\n");
PostNcDestroy(); // perhaps delete the C++ object
return FALSE;
}}
m_strTitle = lpszWindowName; // save title for later
if (!CreateEx(dwExStyle, lpszClassName, lpszWindowName, dwStyle,
rect.left, rect.top, rect.right - rect.left, rect.bottom - rect.top,
pParentWnd->GetSafeHwnd(), hMenu, (LPVOID)pContext))
{
TRACE(traceAppMsg, 0, "Warning: failed to create CFrameWnd.\n");
if (hMenu != NULL)
DestroyMenu(hMenu);
return FALSE;
}
return TRUE;
}
Hi,
Can you please suggest me how to ensure if this much objects are successfully created?
I have the following thing in my code:
//Inside ::InitInstance
if (pDocTemplate = new CMultiDocTemplate(IDR_mdiflsTYPE,
RUNTIME_CLASS(CmdiflsDoc),
RUNTIME_CLASS(CChildFrame), // custom MDI child frame
RUNTIME_CLASS(CmdiflsView) ) != NULL)
cout<<"Successful"
else
cout<<"Failure"
I have such 140 CMULTIDOCTEMPLATE (using new) objects and I got 140 message: "Successful".
Comments from another person:-
If you call the constructor so many times, without freeing, then you probably reach a maximum space of Windows handles, if the constructor loads menu and other resources. That’s why next resource-allocation functions fails. Can you confirm that you really create and keep so many objects?
Is there any better way to ensure if it is a resource allocation/ storage limitation problem? If yes. how can I overcome this?
Thanks in advance!
Chirag Kalra
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Chirag_kalra wrote: if ((hMenu = ::LoadMenu(hInst, lpszMenuName)) == NULL)
can you tell me the error code generated at this time( put @err,hr in watch window of the msdev to get the error string)
Also after the 4th instance is crached, are you able to start other window based applications?
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Thanks for u r response
How to put the error code...Can u explain me in detail.
and Yes I am able to start any other application except mine..
Chirag Kalra
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Chirag_kalra wrote: How to put the error code...Can u explain me in detail.
Actually when the fourth instance is started, your application is crashing or LoadMenu just return the failure?
If it is failing, put a breakpoint in the "TRACE(traceAppMsg, 0, "Warning: failed to load menu for CFrameWnd.\n");" statement and when breakpoint hits, take the watch window in the msdev and put "@err,hr" in it. This will display any error strings if any. And let me know the result.
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Mine application is not crashing.When I run the 4th instance, It is not able to show login screen while the other 3 login screens are visible.
When I debugged then I found the above mentioned line of code due to which it is failing.
I put @err,hr in my watch and found S_OK when I run 4th instance.
Chirag Kalra
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