Source Code for Module elisa.core.utils.notifying_dict

 1  # -*- coding: utf-8 -*- 
 2  # Moovida - Home multimedia server 
 3  # Copyright (C) 2006-2009 Fluendo Embedded S.L. (www.fluendo.com). 
 4  # All rights reserved. 
 5  # 
 6  # This file is available under one of two license agreements. 
 7  # 
 8  # This file is licensed under the GPL version 3. 
 9  # See "LICENSE.GPL" in the root of this distribution including a special 
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11  # 
12  # The GPL part of Moovida is also available under a commercial licensing 
13  # agreement from Fluendo. 
14  # See "LICENSE.Moovida" in the root directory of this distribution package 
15  # for details on that license. 
16   
17  """ 
18  Notifying dictionary. 
19  """ 
20   
21  import gobject 
22   
23   
24 -class Notifier(gobject.GObject): 
25   
26      """ 
27      A notifier that emits an items-changed signal when its associated dictionary 
28      is updated. 
29   
30      The items-changed signal is emitted with three parameters: the dictionary 
31      itself, the key of the modified item, the value of the modified item. 
32      """ 
33   
34      __gsignals__ = \ 
35          {'items-changed': (gobject.SIGNAL_RUN_LAST, gobject.TYPE_PYOBJECT, 
36                            (gobject.TYPE_PYOBJECT, gobject.TYPE_PYOBJECT)), 
37          } 
38   
39  gobject.type_register(Notifier) 
40   
41   
42 -class NotifyingDictionary(dict): 
43   
44      """ 
45      A dictionary that emits a signal when items are set/modified. 
46   
47      The signal is emitted through a L{Notifier} object. 
48      """ 
49   
50      # FIXME: incomplete: it does not override all the dict methods that write: 
51      # - setdefault 
52      # - clear 
53      # - pop 
54      # - popitem 
55      # - __delitem__ 
56      # 
57      # cf. http://www.python.org/doc/2.5.2/lib/typesmapping.html 
58   
59 -    def __init__(self, *args, **kwargs): 
60          dict.__init__(self, *args, **kwargs) 
61          self.notifier = Notifier() 
62   
63 -    def __setitem__(self, key, value): 
64          dict.__setitem__(self, key, value) 
65          self.notifier.emit('items-changed', self, {key: value}) 
66   
67 -    def update(self, other): 
68          dict.update(self, other) 
69          self.notifier.emit('items-changed', self, other) 
70   
71 -    def __deepcopy__(self, memo): 
72          new_dict = self.__class__(self) 
73          return new_dict 
74