sugar-toolkit-gtk3/lib/sugar/graphics/objectchooser.py

# Copyright (C) 2007, One Laptop Per Child
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2 of the License, or (at your option) any later version.
#
# This library 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
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, write to the
# Free Software Foundation, Inc., 59 Temple Place - Suite 330,
# Boston, MA 02111-1307, USA.

import logging
import time

import gobject
import gtk
import dbus

from sugar.datastore import datastore

J_DBUS_SERVICE = 'org.laptop.Journal'
J_DBUS_INTERFACE = 'org.laptop.Journal'
J_DBUS_PATH = '/org/laptop/Journal'

class ObjectChooser(object):
    def __init__(self, title=None, parent=None, flags=None, buttons=None):
        # For backwards compatibility:
        # - We ignore title, flags and buttons.
        # - 'parent' can be a xid or a gtk.gdk.Window

        if title is not None or flags is not None or buttons is not None:
            logging.warning('Invocation of ObjectChooser() has deprecated '
                            'parameters.')

        if parent is None:
            parent_xid = 0
        elif hasattr(parent, 'window') and hasattr(parent.window, 'xid'):
            parent_xid = parent.window.xid
        else:
            parent_xid = parent

        self._parent_xid = parent_xid
        self._main_loop = None
        self._object_id = None
        self._bus = None
        self._chooser_id = None
        self._response_code = gtk.RESPONSE_NONE
        
    def run(self):
        self._object_id = None

        self._main_loop = gobject.MainLoop()

        self._bus = dbus.SessionBus(mainloop=self._main_loop)
        self._bus.add_signal_receiver(
                self.__name_owner_changed_cb,
                signal_name="NameOwnerChanged",
                dbus_interface="org.freedesktop.DBus",
                arg0=J_DBUS_SERVICE)

        obj = self._bus.get_object(J_DBUS_SERVICE, J_DBUS_PATH)
        journal = dbus.Interface(obj, J_DBUS_INTERFACE)
        journal.connect_to_signal('ObjectChooserResponse',
                                  self.__chooser_response_cb)
        journal.connect_to_signal('ObjectChooserCancelled',
                                  self.__chooser_cancelled_cb)
        self._chooser_id = journal.ChooseObject(self._parent_xid)

        gtk.gdk.threads_leave()
        try:
            self._main_loop.run()
        finally:
            gtk.gdk.threads_enter()
        self._main_loop = None

        return self._response_code

    def get_selected_object(self):
        if self._object_id is None:
            return None
        else:
            return datastore.get(self._object_id)

    def destroy(self):
        self._cleanup()

    def _cleanup(self):
        if self._main_loop is not None:
            self._main_loop.quit()
            self._main_loop = None
        self._bus = None

    def __chooser_response_cb(self, chooser_id, object_id):
        if chooser_id != self._chooser_id:
            return
        logging.debug('ObjectChooser.__chooser_response_cb: %r' % object_id)
        self._response_code = gtk.RESPONSE_ACCEPT
        self._object_id = object_id
        self._cleanup()

    def __chooser_cancelled_cb(self, chooser_id):
        if chooser_id != self._chooser_id:
            return
        logging.debug('ObjectChooser.__chooser_cancelled_cb: %r' % chooser_id)
        self._response_code = gtk.RESPONSE_CANCEL
        self._cleanup()

    def __name_owner_changed_cb(self, name, old, new):
        logging.debug('ObjectChooser.__name_owner_changed_cb')
        # Journal service disappeared from the bus
        self._response_code = gtk.RESPONSE_CANCEL
        self._cleanup()