diff options
Diffstat (limited to 'addons/timerevent.py')
-rw-r--r-- | addons/timerevent.py | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/addons/timerevent.py b/addons/timerevent.py new file mode 100644 index 0000000..c7374d0 --- /dev/null +++ b/addons/timerevent.py @@ -0,0 +1,73 @@ +# 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 + +import gobject + +from sugar.tutorius.filters import EventFilter +from sugar.tutorius.properties import TIntProperty + +class TimerEvent(EventFilter): + """ + TimerEvent is a special EventFilter that uses gobject + timeouts to trigger a state change after a specified amount + of time. It must be used inside a gobject main loop to work. + """ + timeout = TIntProperty(15, 0) + + def __init__(self, timeout=None): + """Constructor. + + @param timeout timeout in seconds + """ + super(TimerEvent,self).__init__() + if timeout: + self.timeout = timeout + self._handler_id = None + + def install_handlers(self, callback, **kwargs): + """install_handlers creates the timer and starts it""" + super(TimerEvent,self).install_handlers(callback, **kwargs) + #Create the timer + self._handler_id = gobject.timeout_add_seconds(self.timeout, self._timeout_cb) + + def remove_handlers(self): + """remove handler removes the timer""" + super(TimerEvent,self).remove_handlers() + if self._handler_id: + try: + #XXX What happens if this was already triggered? + #remove the timer + gobject.source_remove(self._handler_id) + except: + pass + + def _timeout_cb(self): + """ + _timeout_cb triggers the eventfilter callback. + + It is necessary because gobject timers only stop if the callback they + trigger returns False + """ + self.do_callback() + return False #Stops timeout + +__event__ = { + "name" : "TimerEvent", + "display_name" : "Timed transition", + "icon" : "clock", + "class" : TimerEvent, + "mandatory_props" : ["timeout"] +} |