From 0c3f127c86af818d260966d2292b199757087157 Mon Sep 17 00:00:00 2001 From: Simon Poirier Date: Sat, 11 Jul 2009 21:39:46 +0000 Subject: repackage --- (limited to 'tutorius/filters.py') diff --git a/tutorius/filters.py b/tutorius/filters.py new file mode 100644 index 0000000..aa8c997 --- /dev/null +++ b/tutorius/filters.py @@ -0,0 +1,204 @@ +# Copyright (C) 2009, Tutorius.org +# Copyright (C) 2009, Vincent Vinet +# +# 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 +import gtk +import logging +logger = logging.getLogger("filters") + +from sugar.tutorius.gtkutils import find_widget +from sugar.tutorius.services import ObjectStore +from sugar.tutorius import properties + + +class EventFilter(properties.TPropContainer): + """ + Base class for an event filter + """ + + next_state = properties.TStringProperty("None") + + def __init__(self, next_state=None): + """ + Constructor. + @param next_state name of the next state + """ + super(EventFilter, self).__init__() + if next_state: + self.next_state = next_state + self._callback = None + + def get_next_state(self): + """ + Getter for the next state + """ + return self.next_state + + def set_next_state(self, new_next_name): + """ + Setter for the next state. Should only be used during construction of + the event_fitler, not while the tutorial is running. + """ + self.next_state = new_next_name + + def install_handlers(self, callback, **kwargs): + """ + install_handlers is called for eventfilters to setup all + necessary event handlers to be able to catch the desired + event. + + @param callback the callback function that will be called + with the event filter as an argument when the event is catched + and validated. + @param **kwargs unused by this handler for now, allows subclasses + to receive information about the context when installing + + Subclasses must call this super method to setup the callback if they + feel like cooperating + """ + self._callback = callback + + def remove_handlers(self): + """ + remove_handlers is called when a state is done so that all + event filters can cleanup any handlers they have installed + + This function will also clear the callback function so that any + leftover handler that is triggered will not be able to change the + application state. + + subclasses must call this super method to cleanup the callback if they + collaborate and use this classe's do_callback() + """ + self._callback = None + + def do_callback(self, *args, **kwargs): + """ + Default callback function that calls the event filter callback + with the event filter as only argument. + """ + if self._callback: + self._callback(self) + +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. + """ + def __init__(self,next_state,timeout_s): + """Constructor. + + @param next_state default EventFilter param, passed on to EventFilter + @param timeout_s timeout in seconds + """ + super(TimerEvent,self).__init__(next_state) + self._timeout = timeout_s + 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 + +class GtkWidgetTypeFilter(EventFilter): + """ + Event Filter that listens for keystrokes on a widget + """ + def __init__(self, next_state, object_id, text=None, strokes=None): + """Constructor + @param next_state default EventFilter param, passed on to EventFilter + @param object_id object tree-ish identifier + @param text resulting text expected + @param strokes list of strokes expected + + At least one of text or strokes must be supplied + """ + super(GtkWidgetTypeFilter, self).__init__(next_state) + self._object_id = object_id + self._text = text + self._captext = "" + self._strokes = strokes + self._capstrokes = [] + self._widget = None + self._handler_id = None + + def install_handlers(self, callback, **kwargs): + """install handlers + @param callback default EventFilter callback arg + """ + super(GtkWidgetTypeFilter, self).install_handlers(callback, **kwargs) + logger.debug("~~~GtkWidgetTypeFilter install") + activity = ObjectStore().activity + if activity is None: + logger.error("No activity") + raise RuntimeWarning("no activity in the objectstore") + + self._widget = find_widget(activity, self._object_id) + if self._widget: + self._handler_id= self._widget.connect("key-press-event",self.__keypress_cb) + logger.debug("~~~Connected handler %d on %s" % (self._handler_id,self._object_id) ) + + def remove_handlers(self): + """remove handlers""" + super(GtkWidgetTypeFilter, self).remove_handlers() + #if an event was connected, disconnect it + if self._handler_id: + self._widget.handler_disconnect(self._handler_id) + self._handler_id=None + + def __keypress_cb(self, widget, event, *args): + """keypress callback""" + logger.debug("~~~keypressed!") + key = event.keyval + keystr = event.string + logger.debug("~~~Got key: " + str(key) + ":"+ keystr) + self._capstrokes += [key] + #TODO Treat other stuff, such as arrows + if key == gtk.keysyms.BackSpace: + self._captext = self._captext[:-1] + else: + self._captext = self._captext + keystr + + logger.debug("~~~Current state: " + str(self._capstrokes) + ":" + str(self._captext)) + if not self._strokes is None and self._strokes in self._capstrokes: + self.do_callback() + if not self._text is None and self._text in self._captext: + self.do_callback() + -- cgit v0.9.1