Gtk::ProgressBar is not being updated inside a for statement

[Adrián Ortega <elfus0 1 gmail com>]

Hello, I'm writing a small application that makes a simple operation 
(i.e. 5+6, 8*9, etc.) and the user gives the amount of time (seconds) 
that operation will take, i.e. if the user enters 8 seconds my 
application will enter in a little loop to wait 8 seconds.

The "wait" function works well, what happens is that the progress bar 
gets updated only after the control exits the function and is at 100% 
and the progress as the job is being done won't be displayed. I only see 
the progress bar at 100% when it has finished the work and not during 
the time it's being done.

I searched a little about this before sending this e-mail, I found I 
should use the static functions in Gtk::Main::events_pending() and 
Gtk::Main::iteration(), I saw a "false" argument should be passed to the 
Gtk::Main::iteration() method, I tried both arguments (true and false) 
none of them worked....

Here is part of the code I use

void wait(double seconds){
clock_t end_wait;
end_wait = clock () + end_wait * CLOCKS_PER_SEC ;
while (clock() < end_wait) {}
}

for(int i=1; i<=max_time; i++){

             wait(1); //Waits one second

             myProgressBar.set_fraction(i/max_time); //it updates the 
GUI until it has returned to the main window loop

              while(Gtk::Main::events_pending()) //this should update 
the progress bar in GUI on each iteration in this for statement, but it 
doesn't

              Gtk::Main::iteration();//I tried both arguments, false 
and true, none of them worked, same result... it gets updated when it 
exits the function that uses this for statement
}

Thanks for your time and help.