straw/ValueMonitor.py

   1 """ ValueMonitor.py
   2
   3 """
   4 __copyright__ = "Copyright (c) 2002-2005 Free Software Foundation, Inc."
   5 __license__ = """
   6 Straw is free software; you can redistribute it and/or modify it under the
   7 terms of the GNU General Public License as published by the Free Software
   8 Foundation; either version 2 of the License, or (at your option) any later
   9 version.
  10
  11 Straw is distributed in the hope that it will be useful, but WITHOUT ANY
  12 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
  13 A PARTICULAR PURPOSE. See the GNU General Public License for more details.
  14
  15 You should have received a copy of the GNU General Public License along with
  16 this program; if not, write to the Free Software Foundation, Inc., 59 Temple
  17 Place - Suite 330, Boston, MA 02111-1307, USA. """
  18
  19
  20 import pygtk
  21 pygtk.require('2.0')
  22 import gobject
  23 import error
  24
  25 class ValueMonitor(object):
  26     def __init__(self, current, timeout, notify, data):
  27         self._previous_value = current
  28         self._value = None
  29         self._timeout = timeout
  30         self._notify = notify
  31         self._data = data
  32         self._connected = True
  33         self._value_changed = False
  34
  35     def get_value(self):
  36         return self._value
  37
  38     def set_value(self, value):
  39         if self._connected:
  40             if value != self._value:
  41                 self._value_changed = True
  42                 gobject.timeout_add(self._timeout, self._check_value)
  43             self._value = value
  44
  45     value = property(get_value, set_value)
  46
  47     def connect(self):
  48         self._connected = True
  49
  50     def disconnect(self):
  51         self.flush()
  52         self._connected = False
  53
  54     def flush(self):
  55         self._check_value()
  56
  57     def _check_value(self):
  58         if (self._connected and self._value_changed and self.value != self._previous_value):
  59             self._notify(self.value, self._data)
  60             self._previous_value = self.value
  61
  62 def create_for_gtkentry(widget, timeout, notify):
  63     vm = ValueMonitor(widget.get_text(), timeout, notify, widget)
  64     def changed(object, *data):
  65         vm.value = object.get_text()
  66     widget.connect("changed", changed)
  67     return vm
  68
  69 def create_for_gtkspin(widget, timeout, notify):
  70     vm = ValueMonitor(widget.get_value_as_int, timeout, notify, widget)
  71     def changed(object, *data):
  72         vm.value = object.get_value_as_int()
  73     widget.connect("value-changed", changed)
  74     return vm