Re: Threading Problem

[Chris Vine <chris cvine freeserve co uk>]

On Saturday 23 September 2006 12:24, Pavel Rojtberg wrote:
> Since I could not find any gtkmm threading tutorial that covers glib
> threads with use of gtkmm, I relied on the pygtk documentation:
> http://www.async.com.br/faq/pygtk/index.py?req=show&file=faq20.001.htp
>
> I used Glib::thread_init() instead of gobject.threads_init(), but could
> not find any equivalent for gobject.idle_add(), so perhaps that is where
> my problems originate from.
>
> Anyway the problem is that sometimes the interface just stops being
> updated while still emmiting events, so I can use the close button.

You cannot access GTK+ in more than one thread without using the global GDK 
lock (and you cannot do it all, with or without the GDK lock, under windows).

This explains how GTK+ interacts with glib threads:
http://developer.gnome.org/doc/API/2.0/gdk/gdk-Threads.html

To post events using gtkmm, see Glib::Dispatcher.  You can also use the raw C 
function g_idle_add() if you wish, but this is not wrapped in glibmm 
(presumably because glibmm provides Glib::Dispatcher, which glib does not).  
Either of these will execute the callback in the thread in which the main 
program loop (and by default GTK+) execute, so avoiding the need to use the 
GDK global lock.  If you use g_idle_add(), make sure the handler returns 
FALSE so that it only fires once.

Chris