GnomeMDI session management (was Re: GNOME CVS: gnome-libs martin)

[Martin Baulig <martin home-of-linux org>]

Perhaps I should explain this a little bit ...

First, in the `save_state' callback function you use something like this:

	session_id = gnome_client_get_id (client);

	/* Save the state using gnome-config stuff. */
	gnome_config_push_prefix (gnome_client_get_config_prefix (client));

	gnome_mdi_save_state (mdi, "Session");

	gnome_config_pop_prefix();
	gnome_config_sync();

This creates a new config section which looks about like this:

	[Session]
	mdi_session=1
	mdi_children=80af948:80afaa8:80afc20
	mdi_windows=80ac198:80d2c78:811f578
	mdi_child_config_80af948=0/0
	mdi_child_views_80af948=811f578
	mdi_child_config_80afaa8=1/0
	mdi_child_views_80afaa8=80ac198:80d2c78:80d2c78
	mdi_child_config_80afc20=2/2
	mdi_child_views_80afc20=80ac198
	mdi_window_80ac198=294/136/984/788
	mdi_window_80d2c78=0/368/719/647
	mdi_window_811f578=0/41/890/435

The `mdi_children' key represents the list of GnomeMDIChild objects which is
read from `mdi->children'- well, pointers are meaningless in config files,
I'm just using them as index values ...

Every entry in the `mdi_children' list has two other keys associated:
`mdi_child_config_<index>' which is a config string representing the
GnomeMDIChild. This string is created by the object itself in its
`get_config_string' signal handler. When restarting, you need to provide
a function which parses this string and creates a new GnomeMDIChild out
of it.

The second one is the `mdi_child_views_<index>' keys which is the list of
views associated with this child, we use the pointer to the toplevel window
as index here. The `mdi_window_<index>' key gives the geometry (x/y/w/h) of
this toplevel window.

When restoring, we first walk the list of children `mdi_children' and create
all of the childs (without creating any views!).

Then, we walk the list of toplevel windows - for each of them we walk the
list of children again, if one of the childs has a view in the current
window, we add it ...

This should restore everything exactly as it was before session-saving.

Martin

On Tue, 29 Sep 1998, Gnome CVS User wrote:

> CVSROOT:	/cvs/gnome
> Module name:	gnome-libs
> Changes by:	martin	98/09/29 16:31:55
> 
> Modified files:
> 	libgnomeui     : ChangeLog Makefile.am gnome-mdi-child.c 
> 	                 gnome-mdi-child.h gnome-mdi.c gnome-mdi.h 
> 	                 libgnomeui.h 
> Added files:
> 	libgnomeui     : gnome-mdi-session.c gnome-mdi-session.h 
> 
> Log message:
> 1998-09-29  Martin Baulig  <martin@home-of-linux.org>
> 
> * gnome-mdi-session.[ch]: New files.
> (GnomeMDIChildCreate): New typedef. This is a pointer to a function
> which parses the config string and creates a new GnomeMDIChild.
> (gnome_mdi_save_state): Call this function when saving state with
> the GnomeMDI object and the name of the config section to use.
> (gnome_mdi_restore_state): Call this function with the GnomeMDI
> object, the name of the config section and a (GnomeMDIChildCreate)
> function pointer.
> 
> * gnome-mdi.c (gnome_mdi_add_toplevel_view): New function. Same as
> `gnome_mdi_add_view', but when using GNOME_MDI_NOTEBOOK we add the
> view to a newly created toplevel window.
> * gnome-mdi.h (gnome_mdi_add_toplevel_view): Added prototype.
> 
> * gnome-mdi-child.c: Added new signal `get_config_string'. This
> should be used in subclasses to return a config string representing
> the object which can be used to recreate it when restarting from
> the session manager.
> * gnome-mdi-child.h (GnomeMDIChildClass): Added new signal handler
> function `get_config_string'.
> 
> * libgnomeui.h: Include `gnome-mdi-session.h'.
> * Makefile.am (libgnomeui_la_SOURCES): Added `gnome-mdi-session.c'.
> (libgnomeuiinclude_HEADERS): Added `gnome-mdi-session.h'.

-----------------------------------------------------------------
   Martin Baulig - Angewandte Mathematik - Universitaet Trier
   martin@home-of-linux.org, http://www.home-of-linux.org/
------------------------------------------------------------------