frontends: added a host_listener module which manage a listener launched when host is ready, useful to instantiate things on host in optional modules (e.g. menus).

frontends/src/tools/host_listener.py

@@ -0,0 +1,45 @@
+#!/usr/bin/python
+# -*- coding: utf-8 -*-
+
+# SAT: a jabber client
+# Copyright (C) 2009, 2010, 2011, 2012, 2013, 2014 Jérôme Poisson (goffi@goffi.org)
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+"""This module is only used launch callbacks when host is ready, used for early initialisation stuffs"""
+
+
+listeners = []
+
+def addListener(cb):
+    """Add a listener which will be called when host is ready
+
+    @param cb: callback which will be called when host is ready with host as only argument
+    """
+    listeners.append(cb)
+
+def callListeners(host):
+    """Must be called by frontend when host is ready.
+
+    The call will launch all the callbacks, then remove the listeners list.
+    @param host(QuickApp): the instancied QuickApp subclass
+    """
+    global listeners
+    while True:
+        try:
+            cb = listeners.pop(0)
+            cb(host)
+        except IndexError:
+            break
+    del listeners