Do not unnecessarily instantiate the NotificationCenter

blink/contacts.py

@@ -332,8 +332,7 @@ class GoogleContactsManager(object):
 
     def _NH_SIPApplicationWillStart(self, notification):
         settings = SIPSimpleSettings()
-        notification_center = NotificationCenter()
-        notification_center.add_observer(self, name='CFGSettingsObjectDidChange', sender=settings)
+        notification.center.add_observer(self, name='CFGSettingsObjectDidChange', sender=settings)
         authorization_token = settings.google_contacts.authorization_token
         if authorization_token:
             call_in_gui_thread(self.contact_model.addGroup, self.contact_model.google_contacts_group)
@@ -342,8 +341,7 @@ class GoogleContactsManager(object):
             self.remove_group()
 
     def _NH_SIPApplicationWillEnd(self, notification):
-        notification_center = NotificationCenter()
-        notification_center.remove_observer(self, name='CFGSettingsObjectDidChange', sender=SIPSimpleSettings())
+        notification.center.remove_observer(self, name='CFGSettingsObjectDidChange', sender=SIPSimpleSettings())
         if self.greenlet is not None:
             api.kill(self.greenlet, api.GreenletExit())
 

blink/mainwindow.py

@@ -542,9 +542,8 @@ class MainWindow(base_class, ui_class):
 
     def _NH_SIPApplicationDidStart(self, notification):
         self.load_audio_devices()
-        notification_center = NotificationCenter()
-        notification_center.add_observer(self, name='CFGSettingsObjectDidChange')
-        notification_center.add_observer(self, name='AudioDevicesDidChange')
+        notification.center.add_observer(self, name='CFGSettingsObjectDidChange')
+        notification.center.add_observer(self, name='AudioDevicesDidChange')
 
     def _NH_AudioDevicesDidChange(self, notification):
         for action in self.output_device_menu.actions():

blink/preferences.py

@@ -1276,9 +1276,8 @@ class PreferencesWindow(base_class, ui_class):
     def _NH_SIPApplicationDidStart(self, notification):
         self._sync_defaults()
         self.load_settings()
-        notification_center = NotificationCenter()
-        notification_center.add_observer(self, name='AudioDevicesDidChange')
-        notification_center.add_observer(self, name='CFGSettingsObjectDidChange')
+        notification.center.add_observer(self, name='AudioDevicesDidChange')
+        notification.center.add_observer(self, name='CFGSettingsObjectDidChange')
 
     def _NH_AudioDevicesDidChange(self, notification):
         self.load_audio_devices()

blink/sessions.py

@@ -427,8 +427,7 @@ class SessionItem(QObject):
         digit_map = {'*': 'star'}
         filename = 'sounds/dtmf_%s_tone.wav' % digit_map.get(notification.data.digit, notification.data.digit)
         player = WavePlayer(SIPApplication.voice_audio_bridge.mixer, Resources.get(filename))
-        notification_center = NotificationCenter()
-        notification_center.add_observer(self, sender=player)
+        notification.center.add_observer(self, sender=player)
         SIPApplication.voice_audio_bridge.add(player)
         player.start()
 
@@ -440,8 +439,7 @@ class SessionItem(QObject):
 
     def _NH_DNSLookupDidSucceed(self, notification):
         settings = SIPSimpleSettings()
-        notification_center = NotificationCenter()
-        notification_center.remove_observer(self, sender=notification.sender)
+        notification.center.remove_observer(self, sender=notification.sender)
         if self.pending_removal:
             return
         streams = []
@@ -459,8 +457,7 @@ class SessionItem(QObject):
         self.session.connect(ToHeader(self.uri), routes, streams)
 
     def _NH_DNSLookupDidFail(self, notification):
-        notification_center = NotificationCenter()
-        notification_center.remove_observer(self, sender=notification.sender)
+        notification.center.remove_observer(self, sender=notification.sender)
         if self.pending_removal:
             return
         self.audio_stream = None
@@ -632,12 +629,10 @@ class SessionItem(QObject):
             self._cleanup()
 
     def _NH_WavePlayerDidFail(self, notification):
-        notification_center = NotificationCenter()
-        notification_center.remove_observer(self, sender=notification.sender)
+        notification.center.remove_observer(self, sender=notification.sender)
 
     def _NH_WavePlayerDidEnd(self, notification):
-        notification_center = NotificationCenter()
-        notification_center.remove_observer(self, sender=notification.sender)
+        notification.center.remove_observer(self, sender=notification.sender)
 
 
 class Conference(object):