Re: What is the minimum number of lines to update a gui window without user clicking a button

["L. D. James" <ljames apollo3 com>]

On 08/19/2013 05:22 AM, Markus Elfring wrote:
> > As far as you seeing a technical problem, is it possible that you 
> > could post some code that would actually work to identify the problem?
>
> Your function "HelloWorld::cpp_app" indicated in this example that it 
> will execute for some seconds. I got doubts that the graphical user 
> interface will be as responsive as you might expect it.
> A well-known approach is to perform long lasting data processing in a 
> dedicated thread which is separate from the one which serves the user 
> interface. You need to be very careful with synchronisation so that 
> you avoid thread-unsafe data accesses.
> http://en.wikipedia.org/wiki/Synchronization_%28computer_science%29
Thanks, Markus.  While I can't understand what you're suggesting, I 
really appreciate the input as well as the specifics.  I have all the 
documentations that the users from the list has given me.  I'm studying 
all of it.  It's a lot for a novice.  But I'm not taking any of it light.

Most of the details don't have examples that I can test and I'm spending 
a lot of time cross referencing trying to understand the terms in the 
technical documentations.

As far as the function executing for some seconds, it executes for 
fractions of a second, minutes, hours, perfectly totally as I expect as 
well as totally as desired.

As far as I can see, the function that you picked out is the exact 
function that was provided to me by Alan, and discussed by a number of 
the professionals in this mail list as being functional.  The only 
difference as I can see is the name.  I took Alan's code and tried to 
learn it in such that I could rewrite it and give descriptive names 
according to what I was looking for the function to do.

I also changed the widget from label to textview.

Can you tell me what is different between the two functions:

My example:
HelloWorld::cpp_app

Alan's example:
myLabel::myprocess1

By the way, I left the "HelloWorld" part because I was trying to keep it 
as consistent with the example in the documentation tutorial as 
possible.  The class and function names are different in my actual 
application.  I'm able to make this differences because (I thought) I 
had come to understand what Kjell and Alan had given me.

I'm not good enough to read the highly technical links that you're 
providing me with to make radical changes to the code at this point.  
Kjell recognized the tutorial conatains a chapter on multi-threaded 
programs (from this message:
New multi-threaded example program in the gtkmm tutorial:
https://mail.gnome.org/archives/gtkmm-list/2013-August/msg00055.html

He indicated that it lacked  an example.  The lack of example makes it 
hard for a novice to grasp (as in my case).  So after Alan's assistance, 
which actually resolved my issue, Kjell added a tutorial with an 
example, which I tried to model my code after.

If there is a difference between Alan's code and my updated version, I'd 
appreciate knowing the difference.  I still wouldn't be able to change 
it without an example of the specific lines that would fix it.  Any 
changes that I made will actually brake the code and the gui window 
would lost it's responsiveness, or not display at all.

This was happening when I simply tried to change Alan's code from a 
label widget to a textview widget.  The lost of functionality was the 
purpose of this thread.  I was hoping to see the bare essentials.  I 
thought, after many hours that I had found the key (studying Alan's and 
Kjell's examples).

I'm studying in detail the links that you're providing, but I can't see 
from those links what specific I should change and still have the code 
function as desired.

-- L. James

--
L. D. James
ljames apollo3 com
www.apollo3.com/~ljames

> > I can't say I fully understand it.
>
> Do you like a different description about GUI architectures?
> http://martinfowler.com/eaaDev/uiArchs.html
>
> Regards,
> Markus