Convert PS bindings instantiation into a singleton to cut resource usage

shell/ChatController.py

@@ -1,7 +1,7 @@
 from sugar import env
 from sugar.chat.BuddyChat import BuddyChat
 from sugar.activity import ActivityFactory
-from sugar.presence.PresenceService import PresenceService
+from sugar.presence import PresenceService
 from sugar.p2p.Stream import Stream
 from sugar.chat.Chat import Chat
 
@@ -21,7 +21,7 @@ class ChatController:
 			del self._id_to_name[activity_id]
 
 	def listen(self):
-		self._pservice = PresenceService()
+		self._pservice = PresenceService.get_instance()
 
 		self._pservice.register_service_type(BuddyChat.SERVICE_TYPE)
 		self._service = self._pservice.register_service(env.get_nick_name(),

shell/Owner.py

@@ -25,7 +25,7 @@ class ShellOwner(object):
 			fd.close()
 			break
 
-		self._pservice = PresenceService.PresenceService()
+		self._pservice = PresenceService.get_instance()
 
 	def announce(self):
 		# Create and announce our presence

shell/PresenceView.py

@@ -2,7 +2,7 @@ import gtk
 import gobject
 import dbus
 
-from sugar.presence.PresenceService import PresenceService
+from sugar.presence import PresenceService
 from sugar.presence.Service import Service
 from sugar.chat.BuddyChat import BuddyChat
 
@@ -20,7 +20,7 @@ class PresenceView(gtk.VBox):
 		self._activity_ps = None
 		self._shell = shell
 
-		self._pservice = PresenceService()
+		self._pservice = PresenceService.get_instance()
 		self._pservice.connect("activity-appeared", self._activity_appeared_cb)
 		
 		self._setup_ui()

shell/Shell.py

@@ -173,7 +173,7 @@ class Shell(gobject.GObject):
 		if activity:
 			activity.present()
 		else:
-			pservice = PresenceService.PresenceService()
+			pservice = PresenceService.get_instance()
 			activity_ps = pservice.get_activity(activity_id)
 
 			if activity_ps:

shell/home/FriendsModel.py

@@ -1,6 +1,6 @@
 import gobject
 
-from sugar.presence.PresenceService import PresenceService
+from sugar.presence import PresenceService
 
 class Friend:
 	def __init__(self, buddy):
@@ -22,7 +22,7 @@ class FriendsModel(gobject.GObject):
 		
 		self._friends = []
 		
-		self._pservice = PresenceService()
+		self._pservice = PresenceService.get_instance()
 		self._pservice.connect("buddy-appeared", self.__buddy_appeared_cb)
 
 		for buddy in self._pservice.get_buddies():

shell/home/MeshModel.py

@@ -1,6 +1,6 @@
 import gobject
 
-from sugar.presence.PresenceService import PresenceService
+from sugar.presence import PresenceService
 from sugar import conf
 
 class ActivityInfo:
@@ -32,7 +32,7 @@ class MeshModel(gobject.GObject):
 		
 		self._activities = {}
 		
-		self._pservice = PresenceService()
+		self._pservice = PresenceService.get_instance()
 		self._pservice.connect("service-appeared", self.__service_appeared_cb)
 
 		for service in self._pservice.get_services():

sugar/presence/PresenceService.py

@@ -206,6 +206,14 @@ class PresenceService(gobject.GObject):
 	def unregister_service_type(self, stype):
 		self._ps.unregisterServiceType(stype)
 
+_ps = None
+def get_instance():
+	global _ps
+	if not _ps:
+		_ps = PresenceService()
+	return _ps
+
+
 def start():
 	bus = dbus.SessionBus()
 	ps = dbus.Interface(bus.get_object(DBUS_SERVICE, DBUS_PATH), DBUS_INTERFACE)