app/soc/logic/menu.py

   1 #!/usr/bin/python2.5
   2 #
   3 # Copyright 2008 the Melange authors.
   4 #
   5 # Licensed under the Apache License, Version 2.0 (the "License");
   6 # you may not use this file except in compliance with the License.
   7 # You may obtain a copy of the License at
   8 #
   9 #   http://www.apache.org/licenses/LICENSE-2.0
  10 #
  11 # Unless required by applicable law or agreed to in writing, software
  12 # distributed under the License is distributed on an "AS IS" BASIS,
  13 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14 # See the License for the specific language governing permissions and
  15 # limitations under the License.
  16
  17 """Representations and manipulation of arbitrarily nested menus.
  18 """
  19
  20 __authors__ = [
  21   '"Todd Larsen" <tlarsen@google.com>',
  22   ]
  23
  24
  25 from django.utils import datastructures
  26
  27
  28 class Menu:
  29   """Ordered collection of MenuItem objects.
  30
  31   MenuItems are retrievable as an ordered list or individually by their
  32   MenuItem.text key.
  33   """
  34
  35   def __init__(self, items=None):
  36     """Initializes ordered list of MenuItems.
  37
  38     Args:
  39       items: list of MenuItem objects in display order
  40     """
  41     if not items:
  42       items = []
  43
  44     items = [(i.name, i) for i in items]
  45     self._items = datastructures.SortedDict(data=items)
  46
  47   def getItem(self, name):
  48     """Returns a MenuItem retrieved by its MenuItem.text."""
  49     return self._items.get(name)
  50
  51   def setItem(self, item):
  52     """Overwrites an existing MenuItem, or appends a new one."""
  53     self._items[item.name] = item
  54
  55   def delItem(self, name):
  56     """Removes an existing MenuItem."""
  57     del self._items[name]
  58
  59   def _getItems(self):
  60     """Returns an ordered list of the MenuItems."""
  61     return self._items.values()
  62
  63   items = property(_getItems, doc=
  64     """Read-only list of MenuItems, for use in templates.""")
  65
  66
  67 class MenuItem:
  68   """Provides menu item properties as easily-accessible attributes.
  69   """
  70
  71   def __init__(self, name, value=None, selected=False, annotation=None,
  72                 sub_menu=None):
  73     """Initializes the menu item attributes from supplied arguments.
  74
  75     Args:
  76       name: name of the menu item
  77       value: optional value associated with the menu item;
  78         default is None
  79       selected: Boolean indicating if this menu item is selected;
  80         default is False
  81       annotation: optional annotation associated with the menu item;
  82         default is None
  83       sub_menu: a Menu of sub-items to display below this menu item;
  84         default is None, indicating no sub-menu
  85     """
  86     self.name = name
  87     self.value = value
  88     self.selected = selected
  89     self.annotation = annotation
  90     self.sub_menu = sub_menu