How can I use GetModify/SetModify within CRichEditView - C / C++ / MFC Discussion Boards

Re: lbuttonDown out of a mode window, witch message is spring?

Nishad S1-Apr-09 19:48

1-Apr-09 19:48

Your question is not clear.

Did you use any language translator? Then it is better to translate back to your language to ensure that what is translated is correct or not.

- ns ami -

Using 2 thread i receive a message " Access violation reading location 0x0000001c ". The cmd that generate the error is simply CString utilization...

SNArruda1-Apr-09 13:02

SNArruda

1-Apr-09 13:02

Hi, someone can help with this ?

The objects composition are:

My user interface ... STProfissional ... Do_Start() ... Doing()
.....................
..................... STFabrica ....... STProducao ... STCelula ... STPacoteFabrica ... Move_()
.......................................
....................................... STLogistica ... STProjeto ... STPacoteCliente

Thread 1 = My user interface
Thread 2 = Worker thread started inside profissional (See code). (Blackground).

From STProfessional i would like to start Move_EntradaToBaseline() in STPacoteFabrica ...

My project is basicaly: Inside STFabrica, STProducao, STCelula, STPacoteFAbrica, STLogistica, STProjeto e STPacoteCliente i will make text files containing tasks informations and i put then into directories where a worker Thread (Thread 2) get it and manage it, openig it, reading the tasks informations e calling the apropriated function inside classes STFabrica, STProducao, STCelula, STPacoteFAbrica, STLogistica, STProjeto e STPacoteCliente that efectively do the task.

My Objects (Or classes if you prefer) are just a Set of CString object containing informations about directories, Names, Caracteristics,etc. Sametimes i use deque<cstring> for mantain necessary lists.

I receive the error when was did my first test that call Move_EntradaToBaseline()...(Thread 1, STPacoteFabrica.cpp) from Doing() (Thread 2, STProfessional.cpp) and the error happen.

I noted that, when i put a breakpoint in the line where the error heappen, Looking for variables content, they are invalid, with dirty content or invalid pointers ... I don´t now wy this heappen.

if someone needs i can send the code files ... I realy need help ... the approuch is essencial in my project.

Sorry by poor english, I´m brasiliam and student for this language ...

Re: Using 2 thread i receive a message " Access violation reading location 0x0000001c ". The cmd that generate the error is simply CString utilization...

Stuart Dootson1-Apr-09 13:33

Stuart Dootson

1-Apr-09 13:33

SNArruda wrote:
I receive the error when was did my first test that call Move_EntradaToBaseline()...(Thread 1, STPacoteFabrica.cpp) from Doing() (Thread 2, STProfessional.cpp) and the error happen.

Sorry, but if you call a function from the worked thread, it's going to execute in the context of the worked thread, no matter if you think it should be executing in the UI thread.

SNArruda wrote:
I noted that, when i put a breakpoint in the line where the error heappen, Looking for variables content, they are invalid, with dirty content or invalid pointers ... I don´t now wy this heappen.

Do you use any locking or any other technique to make sure that shared data isn't being altered by one of the threads while the other one's looking at it?

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

Re: Using 2 thread i receive a message " Access violation reading location 0x0000001c ". The cmd that generate the error is simply CString utilization...

SNArruda1-Apr-09 14:31

SNArruda

1-Apr-09 14:31

Tanks for your attention ...

Stuart Dootson wrote:
Sorry, but if you call a function from the worked thread, it's going to execute in the context of the worked thread, no matter if you think it should be executing in the UI thread.

so, there are a way to start a function directly in a UI Thread context from worker thread context ?

Stuart Dootson wrote:
Do you use any locking or any other technique to make sure that shared data isn't being altered by one of the threads while the other one's looking at it?

Here, i have many questions about how the things happen, i´m very new about it. above you tell me about context´s ... wy the data needs to be locked before your use ? ... each context don´t have your own data ... or for example the data STPacoteFabrica::p_sPacoteFabrica (CString having a path for a diretory) belong of 2 context´s ?

There are way to attach files here ? I would like to attach the .h and .cpp files

Re: Using 2 thread i receive a message " Access violation reading location 0x0000001c ". The cmd that generate the error is simply CString utilization...

Stuart Dootson1-Apr-09 21:44

Stuart Dootson

1-Apr-09 21:44

SNArruda wrote:
so, there are a way to start a function directly in a UI Thread context from worker thread context

Not really - although if you send/post a message to one of the UI thread's windows, the message handler will be executed in the UI thread - that's about the best way of communicating between worker and UI threads.

SNArruda wrote:
wy the data needs to be locked before your use ? ... each context don´t have your own data ... or for example the data STPacoteFabrica::p_sPacoteFabrica (CString having a path for a diretory) belong of 2 context´s ?

Class members, heap allocated data - it's all visible to both threads. If the UI thread modifies some data while the worker thread is accessing it...you've got a problem. If the worker thread modifies some data while the UI thread is accessing it...you've got a problem. You use locks to ensure that only one thread can access data at a time.

Can I suggest you look at some introductory thread information? There are several on CP[^].

SNArruda wrote:
There are way to attach files here ? I would like to attach the .h and .cpp files

I don't believe there are.

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

Re: Using 2 thread i receive a message " Access violation reading location 0x0000001c ". The cmd that generate the error is simply CString utilization...

ThatsAlok1-Apr-09 18:19

ThatsAlok

1-Apr-09 18:19

have you applied some type of syncronization mechanism in your program. if not, try critcal_section

"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow
Never mind - my own stupidity is the source of every "problem" - Mixture

cheers,
Alok Gupta
VC Forum Q&A :- I/IV
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Re: Using 2 thread i receive a message " Access violation reading location 0x0000001c ". The cmd that generate the error is simply CString utilization...

SNArruda2-Apr-09 14:30

SNArruda

2-Apr-09 14:30

Tanks Alok Gupta,

I'll study the critical_section.

But, one thing resistance to go into my mind.

I have two threads. The primary thread that corresponding to UI thread and a worker thread.

There are a way to call, from a Worker thread, a function in primary thread context without messages. Simply geting a pointer and starting it.

Another example, if i create another worker thread, so, i will have a primary thread, worker_thread_1 and worker_thread_2, and will desired call from worker_thread_1::fx(), from its context, the worker_thread_2::fy(), in its own context.

I Realy need to do this, or samething like.

if you need, see my .h and .cpp files attached early

How can I use GetModify/SetModify within CRichEditView

Joseph Marzbani1-Apr-09 11:36

Joseph Marzbani

1-Apr-09 11:36

I've a SDI Application and want to Enable/Disable some menu items under some specific conditions. My CAppView is derived from CRichEditView and I used the following code to find if it's changed since I set the Modification Flah (using SetModify) or not:

//Some conditions
GetRichEditCtrl().SetModify( FALSE ) ;

//Some other conditions
GetRichEditCtrl().SetModify( TRUE ) ;

/////////////////////////////////////////////////

if ( GetRichEditCtrl().GetModify() )
{
    // Do something
}

but GetRichEditCtrl().GetModify() allways returns TRUE, even if I set GetRichEditCtrl().SetModify( TRUE )

Any idea?

Thank you masters!

Re: How can I use GetModify/SetModify within CRichEditView

Rick York1-Apr-09 11:49

Rick York

1-Apr-09 11:49

Look at the usage of the ON_UPDATE_COMMAND_UI macro.

Re: How can I use GetModify/SetModify within CRichEditView

Stuart Dootson1-Apr-09 11:57

Stuart Dootson

1-Apr-09 11:57

Jusef Marzbany wrote:
but GetRichEditCtrl().GetModify() allways returns TRUE, even if I set GetRichEditCtrl().SetModify( TRUE )

You use GetRichEditCtrl().SetModify( FALSE ) to reset the modification flag to false - see here[^].

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

Extracting a string from a tab-delimited file

SomeGuy6541-Apr-09 11:19

SomeGuy654

1-Apr-09 11:19

I'm trying to create a small function for a program that should extract the data as a string from a column of a tab delimited text file. It seems to be returning an empty string though.

Let me know if you notice what's wrong with this function. Edit: this is VC++

Function:

string split_row(string line, int column)
{
	// The first column would be column 1 for this function. Pass in the string 
	// we want to parse and the column we want parsed. Will return just the string 
	// from the column indicated for this row.

	int c_temp;
	string data;
	int pos;
	const string delimiter = "\t";

	for(c_temp=1; c_temp<=9; c_temp++)
	{
		pos = line.find_first_of(delimiter);
		if (c_temp != column)
		{
			line.erase(0, pos);
		}
		else
		{
			data = line.substr(0, pos-1);
			break;
		}
	}
	return data;
}

If the string "row", below, were to be:

12	test Phone	2009

And we called split_row(row, 2) it should return "test Phone".

Thanks! (sorry for the stupid username)

Re: Extracting a string from a tab-delimited file

Stuart Dootson1-Apr-09 12:05

Stuart Dootson

1-Apr-09 12:05

This code (changed bits in bold) seems to work with your test data. I suspect you were forgetting that ranges in STL are half-open, i.e. the last character in the range specification isn't part of the range.

string split_row(string line, int column)
{
// The first column would be column 1 for this function. Pass in the string 
// we want to parse and the column we want parsed. Will return just the string 
// from the column indicated for this row.

   int c_temp;
   string data;
   int pos;
   const string delimiter = "\t";

   for(c_temp=1; c_temp<=9; c_temp++)
   {
      pos = line.find_first_of(delimiter);
      if (c_temp != column)
      {
         line.erase(0, pos+1);
      }
      else
      {
         data = line.substr(0, pos);
         break;
      }
   }
   return data;
}

Ought to add a check that pos != std::string::npos, as that indicates no tab, so a possible error condition.

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

Re: Extracting a string from a tab-delimited file

SomeGuy6541-Apr-09 14:13

SomeGuy654

1-Apr-09 14:13

Works perfectly with your change. Thank you very much!

XML Visual Studio 2003 MFC C++

ScotDolan1-Apr-09 10:59

ScotDolan

1-Apr-09 10:59

I am developing a new software driver. The software will be package into DLL. I would like to store the configuration information for the DLL in a XML file.. I found lots of different XML Parser pojects on Code Project. However, i would prefer to use one from msdn if there is one available. Does anyone have any recomendations.

Scott

Scott Dolan
Jernie Corporation
Engineering & Manufacturing
Software, Hardware, & Enclosures

Re: XML Visual Studio 2003 MFC C++

CPallini1-Apr-09 11:09

CPallini

1-Apr-09 11:09

ScotDolan wrote:
i would prefer to use one from msdn if there is one available

I bet there is [^].
Smile | :)

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

Re: XML Visual Studio 2003 MFC C++

Stuart Dootson1-Apr-09 11:55

Stuart Dootson

1-Apr-09 11:55

If you don't want to use MSXML, there is an alternative[^] from MS that claims to be 'lighter'.

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

safe-cast serialization

Member 26037721-Apr-09 7:57

Member 2603772

1-Apr-09 7:57

Is there a way in C++ to serialize objects into a char buffer without using reinterpret_cast or c-style casting (and backwards on the other end)? I also don't want to use C++ streams. I don't care how difficult it is.
Thanks

Re: safe-cast serialization

CPallini1-Apr-09 8:09

CPallini

1-Apr-09 8:09

IMHO your requirements are not wise (why do you want to avoid cast?).
Smile | :)

Re: safe-cast serialization

Member 26037721-Apr-09 9:45

Member 2603772

1-Apr-09 9:45

c-style cast is dangerous and hard to find in code. reinterpret_cast is not portable and just as dangerous as c-style. i want a typed way to serialize/deserialize.

Re: safe-cast serialization

CPallini1-Apr-09 10:50

CPallini

1-Apr-09 10:50