From b658de9cf3cb526f8492a54dab19e8238c9edb9b Mon Sep 17 00:00:00 2001 From: mike Date: Mon, 05 Oct 2009 15:42:07 +0000 Subject: LP 439980 : Adding missed actions in previous checkins --- (limited to 'addons/oncewrapper.py') diff --git a/addons/oncewrapper.py b/addons/oncewrapper.py new file mode 100644 index 0000000..fb0196f --- /dev/null +++ b/addons/oncewrapper.py @@ -0,0 +1,59 @@ +# Copyright (C) 2009, Tutorius.org +# +# 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 + +from sugar.tutorius.actions import * + +class OnceWrapper(Action): + """ + Wraps a class to perform an action once only + + This ConcreteActions's do() method will only be called on the first do() + and the undo() will be callable after do() has been called + """ + + action = TAddonProperty() + + def __init__(self, action): + Action.__init__(self) + self._called = False + self._need_undo = False + self.action = action + + def do(self): + """ + Do the action only on the first time + """ + if not self._called: + self._called = True + self.action.do() + self._need_undo = True + + def undo(self): + """ + Undo the action if it's been done + """ + if self._need_undo: + self.action.undo() + self._need_undo = False + + +__action__ = { + 'name' : 'OnceWrapper', + 'display_name' : 'Execute an action only once', + 'icon' : 'once_wrapper', + 'class' : OnceWrapper, + 'mandatoryprops' : ['action'] +} -- cgit v0.9.1