Write a chat activity, remove some unused code

activities/chat/Makefile.am

@@ -1,6 +1,6 @@
 sugardir = $(pkgdatadir)/activities/chat
 sugar_PYTHON =			\
 	__init__.py		\
-	ChatActivity.py
+	chatactivity.py
 
 EXTRA_DIST = chat.activity

activities/chat/chat.activity

@@ -3,4 +3,4 @@ name = GroupChat
 icon = activity-chat
 id = org.laptop.ChatActivity
 python_module = chat.chatactivity.ChatActivity
-show_launcher = no
+show_launcher = yes

activities/chat/chatactivity.py

@@ -17,8 +17,33 @@
 from gettext import gettext as _
 
 from sugar.activity.Activity import Activity
+from sugar.chat.Chat import Chat
+from sugar.p2p.Stream import Stream
 
-class GroupChatActivity(Activity):
+class ChatActivity(Activity):
 	def __init__(self):
 		Activity.__init__(self)
+
+		self._group_stream = None
+
 		self.set_title(_('Group chat'))
+
+		self._chat = Chat()
+		self.add(self._chat)
+		self._chat.show()
+
+	def join(self, activity_ps):
+		Activity.join(self, activity_ps)
+		self._setup_stream()
+
+	def share(self):
+		Activity.share(self)
+		self._setup_stream()
+
+	def _setup_stream(self):
+		self._group_stream = Stream.new_from_service(self._service)
+		self._group_stream.set_data_listener(self._group_recv_message)
+		self._chat.set_stream_writer(self._group_stream.new_writer())
+
+	def _group_recv_message(self, address, msg):
+		self._chat.recv_message(msg)