Use libunique in the shell to have a single-instance shell

This requires a slight API meaning change in libslab:
create_main_window() doesn't run gtk_main() anymore. This wasn't a good
thing anyway.

configure.in

@@ -95,7 +95,7 @@ COMMON_MODULES="gtk+-2.0 >= 2.15.0 dnl
  gnome-desktop-2.0 >= 2.25.1"
 PKG_CHECK_MODULES(CAPPLET, $COMMON_MODULES)
 PKG_CHECK_MODULES(GNOMECC, $COMMON_MODULES libgnome-menu >= 2.10.1)
-PKG_CHECK_MODULES(GNOMECC_SHELL, $COMMON_MODULES libgnome-menu)
+PKG_CHECK_MODULES(GNOMECC_SHELL, $COMMON_MODULES libgnome-menu unique-1.0)
 PKG_CHECK_MODULES(DBUS, dbus-1 dbus-glib-1)
 PKG_CHECK_MODULES(GNOME_DESKTOP, gnome-desktop-2.0)
 PKG_CHECK_MODULES(DEFAULT_APPLICATIONS_CAPPLET, libxml-2.0)

libslab/app-shell.c

@@ -138,7 +138,6 @@ create_main_window (AppShellData * app_data, const gchar * app_name, const gchar
 	gtk_window_set_position (GTK_WINDOW (app_data->main_app), GTK_WIN_POS_CENTER);
 	if (!hidden)
 		show_shell (app_data);
-	gtk_main ();
 
 	return TRUE;
 }

shell/control-center.c

@@ -20,15 +20,12 @@
 
 #include "config.h"
 
-#include <string.h>
-
 #include <glib/gi18n.h>
 #include <gtk/gtk.h>
 #include <libgnome/gnome-desktop-item.h>
-#include <dirent.h>
+#include <unique/unique.h>
 
-#include "app-shell.h"
+#include <libslab/slab.h>
-#include "slab-gnome-util.h"
 
 void handle_static_action_clicked (Tile * tile, TileEvent * event, gpointer data);
 static GSList *get_actions_list ();
@@ -101,10 +98,44 @@ handle_static_action_clicked (Tile * tile, TileEvent * event, gpointer data)
 	g_free (temp);
 }
 
+static UniqueResponse
+message_received_cb (UniqueApp         *app,
+		     UniqueCommand      command,
+		     UniqueMessageData *message,
+		     guint              time,
+		     gpointer           user_data)
+{
+	UniqueResponse  res;
+	AppShellData   *app_data = user_data;
+
+	switch (command) {
+	case UNIQUE_ACTIVATE:
+		/* move the main window to the screen that sent us the command */
+		gtk_window_set_screen (GTK_WINDOW (app_data->main_app),
+				       unique_message_data_get_screen (message));
+		if (!app_data->main_app_window_shown_once)
+			show_shell (app_data);
+
+		gtk_window_present_with_time (GTK_WINDOW (app_data->main_app),
+					      time);
+
+		gtk_widget_grab_focus (SLAB_SECTION (app_data->filter_section)->contents);
+
+		res = UNIQUE_RESPONSE_OK;
+		break;
+	default:
+		res = UNIQUE_RESPONSE_PASSTHROUGH;
+		break;
+	}
+
+	return res;
+}
+
 int
 main (int argc, char *argv[])
 {
 	gboolean hidden = FALSE;
+	UniqueApp *unique_app;
 	AppShellData *app_data;
 	GSList *actions;
 	GError *error;
@@ -127,6 +158,22 @@ main (int argc, char *argv[])
 		return 1;
 	}
 
+	unique_app = unique_app_new ("org.opensuse.yast-control-center-gnome", NULL);
+	if (unique_app_is_running (unique_app)) {
+		int retval = 0;
+
+		if (!hidden) {
+			UniqueResponse response;
+			response = unique_app_send_message (unique_app,
+							    UNIQUE_ACTIVATE,
+							    NULL);
+			retval = (response != UNIQUE_RESPONSE_OK);
+		}
+
+		g_object_unref (unique_app);
+		return retval;
+	}
+
 	app_data = appshelldata_new ("gnomecc.menu", NULL, CONTROL_CENTER_PREFIX,
 				     GTK_ICON_SIZE_DND, FALSE, TRUE);
 	generate_categories (app_data);
@@ -138,5 +185,13 @@ main (int argc, char *argv[])
 	create_main_window (app_data, "MyControlCenter", _("Control Center"),
 		"gnome-control-center", 975, 600, hidden);
 
+	unique_app_watch_window (unique_app, GTK_WINDOW (app_data->main_app));
+	g_signal_connect (unique_app, "message-received",
+			  G_CALLBACK (message_received_cb), app_data);
+
+	gtk_main ();
+
+	g_object_unref (unique_app);
+
 	return 0;
 };