This lets applications block logout and similar actions ahead
of time. Currently only implemented for D-Bus, but Windows has
very similar API since Vista.
This is fairly basic, allowing applications to learn when
the session manager is about to end the session, and possibly
block this. The only implementation at this point is using the
org.gnome.SessionManager D-Bus interface of gnome-session. It should
be straightforward to port the EggSMClient implementations for
Windows and OS X.
We add the app-menu and menubar public APIs to GtkApplication while
leaving the implementation in GApplication.
The actual implementation will be moved soon.
Sub-classes of GtkApplication might want to override the way an
application window is created - for instance, to hook into GtkBuilder
or to set up some basic UI or state.
A new GtkApplication::create_window() virtual function is added to the
GtkApplicationClass vtable, which returns the newly created GtkWindow.
The gtk_application_create_window() function calls the vfunc and adds
the returned window to the list of windows managed by the application
instance.
Calling gtk_application_add_window() will also set the default window,
if one is not already set.
This commit also removes a spurious g_object_ref_sink() on the newly
created GtkWindow.
This is a work in progress to stub out an application class. The
primary goal is to provide a mechanism for applications to export
GtkActions, and there is a standard "Quit" action.
This is based on GApplication.
Future work:
* Add a way to say "This is my application menubar", which gets
put into all toplevel windows on non-OS-X, and into the top
on OS X.
* Support session management.
* Support application settings.
https://bugzilla.gnome.org/show_bug.cgi?id=127958
