Re: Application suddenly stuck at startup

[Jonathan Ballet <jon multani info>]

Hi,

On 03/02/2013 04:16 AM, Andrey Gursky wrote:
> 2013/3/2, Robert Schroll <rschroll gmail com>:
> > On Fri, Mar 1, 2013 at 7:14 PM, Andrey Gursky <andrey gursky e-mail ua>
> > wrote:
> > > Hi Robert, Jonathan,
> > >
> > > 2013/3/1, Robert Schroll <rschroll gmail com>:  I agree with your
> > > reading of the docs.  It's things like this that
> > > >   leave me perpetually confused about threading.  The one possible
> > > >   explanation I see is that "activate" is a signal of GApplication,
> > > > not
> > > >   GtkApplication.  It could be that GLib signal handlers run outside
> > > > of
> > > >   the Gdk lock, while Gtk signal handlers run inside.
> > > >
> > > >   Hopefully someone who actually understands all of this will comment.
> > > Robert, you're right regarding GLib vs GTK callbacks!

So, I understand I would have to held the GDK lock for GLib callbacks 
but not for the GTK ones, that makes sense.

Robert was also right, the "activate" signal is from GApplication, not 
from GtkApplication. That's why (I guess?) that the lock should be held 
before handling things related to Gtk. This is actually documented in 
the GtkApplication's description [1].

So that was my fault for not reading everything completely.

>  Re: Clarification of GTK/GDK locking pre GTK 4.0
>     http://thread.gmane.org/gmane.comp.gnome.gtk+.general/24817/focus=24834

Eh.
I've been reading the whole thread, as well as other threads on the 
group, and I'm not sure the situation is clarified in my head... :-)
Some says Gdk.thread_* functions are deprecated and everything touching 
Gtk should run in the main thread, some says GLib.idle_add is running in 
the main thread and it's OK but maybe not...

So, say my application is not using any threads (it doesn't create 
threads on its own):

* should I still call Gdk.theads_init()?
* is it safe to use GLib.idle_add() & co? If no, in which context is it 
unsafe?
* must I use Gdk.threads_add_* & co? If yes, in which context must I use 
them?
* is it safe to assume that all my code is running in the main thread, 
and that I can skip using Gdk.threads_* API and that I also don't have 
to use GLib.idle_add API to schedule modifications to my Gtk widgets? [2]

(... probably other questions coming soon).

Actually, is there a document which explains "what are the good 
practices for writing Gtk application (wrt. threads)?"

Regards,

 Jon


[1]: 
http://developer.gnome.org/gtk3/unstable/GtkApplication.html#GtkApplication.description

[2]: in lot of places, my application was using lines like:

   GLib.idle_add(gtk_entry.set_text, "foo bar")

and I was wondering wtf they were doing this. I start to form something 
in my head which looks like the beginning of some understanding of this. 
I'm still not sure though.