|
Hi Mark.
I've ran into the same problems as before. i can't seem to make it work for some reason. Can i email you the code so you could take a look at it ?
thanks,
Chen Ganir.
|
|
|
|
|
Context: In a multithreaded app, two threads share access to an object. The members of the objects class are private and are accessed through mutators and accessors that use critical sections to syncronize.
Problem: Where to put the volatile access modifier go in regards to the object and/or it's class?
Question: Should the object, the members of the objects class, or the object and it's class members be declared using the volatile access modifier?
|
|
|
|
|
What is correct way to update custom dialogbars in document/view MDI architecture when the current document is deactivated or a new document is activated.
I am currently trying to send messages to the CMainFrame:public CMDIFrameWnd when a CView is selected and sets a different active document. This does not take into account other ways in which the Active document might be set (I don't know hat these might be). CMainFrame can see all the dialog bars and should be the one to update them based on the active document when the active document is changed. I was looking for a simple OnActivateDocument() event, or something like it, in CMainFrame couldn't seem to find it.
There has to be a simple way and I am just missing it.
|
|
|
|
|
By design, this is usually done in a CView::OnInitialUpdate() override. If you really must handle
window initialization from another window class then you can define your own WM_ messages or add
methods to your window classes. At that point you're really not tied to the Doc/View architecture
so you may find yourself fighting it.
If you handle scrollbar initialization in a CView::OnInitialUpdate() override then your view
classes will stay within the doc/view framework.
Just call it when you change the view's associated document.
|
|
|
|
|
gor wrote: CMainFrame can see all the dialog bars and should be the one to update them based on the active document when the active document is changed.
I agree. I update dialog bars from CMainFrame in much the same way as you descibe, except that I make the functions public and call them directly from my view/doc classes instead of sending messages. I override CView::OnActivateView() to get the correct action when the current view is deactivated or a new view is activated. The only problem I had with this was coping with the counter-intuitive way the system sets the pActiveView and pDeactiveView parameters (I'm not sure if this is relevant to your enquiry, but I can provide a code sample if you are interested).
I don't know if this is the best approach, but I can vouch for the fact that it works, and that it deals with activation of views by conventional mouse clicks and custom code. It seems strange to me too that there is no function in the CMDIFrameWnd class that can be overridden to achieve this - if you ever discover a better way I would be very interested to hear.
Best Regards
Cliff
|
|
|
|
|
Dear all
I have one project in which I should play data from computer sound card and
record voice from it (By microphone).
I need a class that do above options in real time.
Also I need to receive voice data from network and transmit voice data to it.
Thus I need following classes:
1. Real time classes to send and receive data to and from network.
2. Real time classes to play voice on sound card and receive voice from microphone of system.
May you please give my information in this regards
No My program does not work in real time and after a while I find that some delay exists in playing data and recording it when working with network.
Cheers
Monhi
|
|
|
|
|
Voice/sound communication between PCs is big-business these days so it's unlikely you are going
to have the code given to you, especially if it's good code.
There are some things you need to deal with:
1) Latency. Your sallest buffer size will determine your minimum latency. If you're capturing
or playing audio with 500ms buffer chunks then you have a minimum latency of 500ms (1000ms if
using 500ms buffers for both capture and playback). Solution - keep buffer granularity as small
as possible.
2) Clock drift. Clocks are different on every machine. Generally you'll capture and playback
audio at the same sample rate. If the clock used for timing on the capture side varies from the
one used for playback then your audio drifts over time - the latency increases or decreases.
I have a machine that the latency increases 1s every 10 minutes or so capturing from one device
and playing back on a different device on the same machine. Unnaceptable for real-time 
Solution - you'll think of something. It's a main part of my business so I'm not giving my
solution away - Google search on "clock drift" may yields some hints.
3) Network jitter. With full bandwidth available at all times it's no problem. When this is not
the case (often) it's a problem, causing jitter in the playback (crackles/pops/noise caused by
gaps in the audio stream. You'll probably need to account for this by using some kind of jitter
buffer on at least the playback side. A jitter buffer will add latency so consider that in the
overall design.
|
|
|
|
|
To create a safest release executable, what options we should set when compile vc++ project in vc .Net 2003?
Thanks & Regards,
Suman
|
|
|
|
|
What do you mean by 'safest' ? If you statically link to everything, like MFC, you get a bigger EXE with no external dependancies, is that what you mean ?
Christian Graus - Microsoft MVP - C++
Metal Musings - Rex and my new metal blog
|
|
|
|
|
By 'safest' I meant, compiler should warn if there is any possibility of using uninitialized variable, or something else which will cause runtime error, and whatever the compiler can detect.
Thanks & Regards,
Suman
|
|
|
|
|
During a compilation of C/C++ file, how can i know that the caller project(project which contains that cpp file) is using MFC or not.
Warm Regards,
Mushq
|
|
|
|
|
Check the _MFC_VER macro, if it's an MFC project, that macro is defined as the MFC version.
|
|
|
|
|
Thanks for quick reply, and it is woking fine.
Regards,
Mushq
|
|
|
|
|
I am a new student. I have been through two classes, intro to programing in C++ and then C++ data structures. I bought a book on the STL Library called the Standard Template Library. They said the book was for beginners but I can't understand any of it. Does anyone know where I can find a book for BEGINNERS that is easy to understand.
Thanks
IRS
|
|
|
|
|
Perhaps you should have read a little of the book before buying it. The best person to ask about which book to buy is your teacher. He/She will know of a good book that is suitable for use along side his/her course.
|
|
|
|
|
Thats a good point but unfortuantely I live in Idaho, North Idaho to be exact in a little college town. We dont even have a book store. So I had to purchase it online. The only thing I could read was the descriptions. While you make a good point, my resources are extremely limited. I did ask my teacher he said he didnt know. Hints why I posted this message
thanks
irs
|
|
|
|
|
Standard Template Library is a powerful but quite advanced topic. Do you really need to use STL or you only need a good understanding of C++ (in fact a good understanding of C++ is at least recommended before starting to learn STL). There are also free resources online (e.g. Bruce Eckel's books).
By the way, it's a long time I wish to spend a holyday in Idaho (I live in Italy) any hint?
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.
|
|
|
|
|
I have a pretty good understanding of C++. I have had three classes and written quite a bit of code. I just wish there was a book that broke it down easier than what I have.
As far as Idaho goes, you dont want to spend a Christmas here, its about 15 degrees out and I am looking at a few feet of snow. This is just a great enviroment for school cause there is nothing to do. I am from Tampa Bay, Florida. Couldn't get much done there
in the battle between a rock and a stream, the stream will always prevail, not through strength but through persistance
|
|
|
|
|
irs97 wrote: I have a pretty good understanding of C++.
Lucky guy! Then you have a good knowledge of templates and STL cannot be so hard to understand...
irs97 wrote: I have had three classes
Lucky guy again! Usually one have to code several hundreds before being comfortable with.
To understand STL have a look to MSDN library, there are a lot of good examples.
irs97 wrote: As far as Idaho goes, you dont want to spend a Christmas here, its about 15 degrees out and I am looking at a few feet of snow. This is just a great enviroment for school cause there is nothing to do. I am from Tampa Bay, Florida. Couldn't get much done there
I'm sorry about that. I wish you a merry Christmas and hope you'll be back in Tampa asap.
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.
|
|
|
|
|
Well my your last reply, I can tell that I dont have enough experience. In my data structures class we simply briezed over templates. He told us that stl created templated and we really didnt need to know much about them. Maybe I do need to get some more experience. I was under the assumption that STL was suppose to make things easier. I guess I could be wrong. I thought lists, maps, ques, deques, vectors, linked lists, trees, were already created for you to use. No I am not that lucky my friend, I am just a beginner, by no means and I am great, I am just learning and searching for all the knowledge I can find.
IRS
In the battle between a rock and a stream, the stream will always prevail, not through strength but through persistance
|
|
|
|
|
First, I must apologize to you for my rudeness...
irs97 wrote: I was under the assumption that STL was suppose to make things easier.
This is true but you must know a bit of templates.
irs97 wrote: I thought lists, maps, ques, deques, vectors, linked lists, trees, were already created for you to use.
This is also true, but again, you must know a bit of templates.
Have a look to examples. STL documentation is quite too formal, while examples help you in practice.
Hope that helps.
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.
|
|
|
|
|
I don't have any book reccos but you could check out the STL section[^] here on CP.
|
|
|
|
|
*grin* That's just what I said.
Christian Graus - Microsoft MVP - C++
Metal Musings - Rex and my new metal blog
|
|
|
|
|
Hi friends. I'm a new programmer. In an application, when i click About menu, i want the my About.h dialof form to display. In the MSND library, i saw such an example to display user defined dialogs;
{
Form ^ f = gcnew Form();
f->ShowDialog();
}
And i changed this code to display my About.h form dialog such as;
{
Form ^ About = gcnew Form();
About->ShowDialog();
}
But, i still see the same empty dialog instead of my About.h form. So how can i display this dialog when i click About menu ?
|
|
|
|
|
General 
News 
Suggestion 
Question 
Bug 
Answer 
Joke 
Praise 
Rant 
Admin 
Submit an article or tip
