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diff --git a/lvc/widgets/osx/widgetupdates.py b/lvc/widgets/osx/widgetupdates.py
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+++ b/lvc/widgets/osx/widgetupdates.py
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+# @Base: Miro - an RSS based video player application
+# Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011
+# Participatory Culture Foundation
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 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 General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
+#
+# In addition, as a special exception, the copyright holders give
+# permission to link the code of portions of this program with the OpenSSL
+# library.
+#
+# You must obey the GNU General Public License in all respects for all of
+# the code used other than OpenSSL. If you modify file(s) with this
+# exception, you may extend this exception to your version of the file(s),
+# but you are not obligated to do so. If you do not wish to do so, delete
+# this exception statement from your version. If you delete this exception
+# statement from all source files in the program, then also delete it here.
+
+"""widgetupdates.py -- Handle updates to our widgets
+"""
+
+from PyObjCTools import AppHelper
+
+class SizeRequestManager(object):
+    """Helper object to manage size requests
+
+    If something changes in a widget that makes us want to request a new size,
+    we avoid calculating it immediately.  The reason is that the
+    new-size-request will cascade all the way up the widget tree, and then
+    result in our widget being placed.  We don't necessary want all of this
+    action to happen while we are in the middle of handling an event
+    (especially with TableView).  It's also inefficient to calculate things
+    immediately, since we might do something else to invalidate the size
+    request in the current event.
+
+    SizeRequestManager stores which widgets need to have their size
+    recalculated, then calls do_invalidate_size_request() using callAfter
+    """
+
+    def __init__(self):
+        self.widgets_to_request = set()
+        #app.widgetapp.connect("event-processed", self._on_event_processed)
+
+    def add_widget(self, widget):
+        if len(self.widgets_to_request) == 0:
+            AppHelper.callAfter(self._run_requests)
+        self.widgets_to_request.add(widget)
+
+    def _run_requests(self):
+        this_run = self.widgets_to_request
+        self.widgets_to_request = set()
+        for widget in this_run:
+            widget.do_invalidate_size_request()
+
+    def _on_event_processed(self, app):
+        # once we finishing handling an event, process our size requests ASAP
+        # to avoid any potential weirdness.  Note: that we also schedule a
+        # call using callAfter(), often that will do nothing, but it's
+        # possible size requests get scheduled outside of an event
+        while self.widgets_to_request:
+            self._run_requests()