Source Code for Package orm2.ui

  1  #!/usr/bin/env python 
  2  # -*- coding: iso-8859-1 -*- 
  3   
  4  ##  This file is part of orm, The Object Relational Membrane Version 2. 
  5  ## 
  6  ##  Copyright 2002-2006 by Diedrich Vorberg <diedrich@tux4web.de> 
  7  ## 
  8  ##  All Rights Reserved 
  9  ## 
 10  ##  For more Information on orm see the README file. 
 11  ## 
 12  ##  This program is free software; you can redistribute it and/or modify 
 13  ##  it under the terms of the GNU General Public License as published by 
 14  ##  the Free Software Foundation; either version 2 of the License, or 
 15  ##  (at your option) any later version. 
 16  ## 
 17  ##  This program is distributed in the hope that it will be useful, 
 18  ##  but WITHOUT ANY WARRANTY; without even the implied warranty of 
 19  ##  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the 
 20  ##  GNU General Public License for more details. 
 21  ## 
 22  ##  You should have received a copy of the GNU General Public License 
 23  ##  along with this program; if not, write to the Free Software 
 24  ##  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA 
 25  ## 
 26  ##  I have added a copy of the GPL in the file gpl.txt. 
 27   
 28  # 
 29  # $Log: __init__.py,v $ 
 30  # Revision 1.9  2007/04/14 20:36:45  diedrich 
 31  # Make view raise an exceptin if its didn't run. 
 32  # 
 33  # Revision 1.8  2006/09/19 14:26:25  diedrich 
 34  # View_spec.import_() uses the sys.modules cache to speed things 
 35  # up. Also in debugging mode, it reload() to make sure changes matter. 
 36  # 
 37  # Revision 1.7  2006/09/07 13:56:16  diedrich 
 38  # Added widget_spec mechanism (again). 
 39  # 
 40  # Revision 1.6  2006/09/04 15:56:26  diedrich 
 41  # The view class now has a method called ds() as opposed to an 
 42  # attribute. (This reverts to a previous state due to practical 
 43  # experience). 
 44  # 
 45  # Revision 1.5  2006/07/08 17:10:53  diedrich 
 46  # Changed view.ds() to view.ds like in procedure 
 47  # 
 48  # Revision 1.4  2006/07/04 22:48:41  diedrich 
 49  # Added belongs_to() method to widget class. 
 50  # 
 51  # Revision 1.3  2006/06/10 18:06:12  diedrich 
 52  # Rewrote widget handling 
 53  # 
 54  # Revision 1.2  2006/05/15 21:49:10  diedrich 
 55  # Working on ui basics 
 56  # 
 57  # Revision 1.1  2006/04/28 09:56:41  diedrich 
 58  # Initial commit 
 59  # 
 60  # 
 61   
 62  """ 
 63  Someday there will be user interface 'glue' in this module. Now there 
 64  is just a lot of undocumented code that makes no sense. 
 65  """ 
 66   
 67  import sys, thread, imp 
 68  from string import * 
 69  from orm2 import debug 
 70   
 71  ###################################################################### 
 72  ## Widgets 
 73  ###################################################################### 
 74   
 75  _widget_index = 1 
 76   
 77 -class widget:     
 78 -    def __init__(self, **kw): 
 79          global _widget_index 
 80   
 81          self.params = kw 
 82           
 83          lock = thread.allocate_lock() 
 84          lock.acquire() 
 85          self.__index__ = _widget_index 
 86          _widget_index += 1 
 87          lock.release() 
 88           
 89 -    def __init_dbproperty__(self, dbproperty): 
 90          self.dbproperty = dbproperty 
 91   
 92 -    def __cmp__(self, other): 
 93          """ 
 94          This makes sort() on sequences of widget objects use the _widget_index 
 95          for sorting 
 96          """ 
 97          return cmp(self.__index__, other.__index__) 
 98   
 99 -    def belongs_to(self, module_name): 
100          raise NotImplementedError() 
101   
102 -    def __call__(self, dbobj, **kw): 
103          params = self.params.copy() 
104          params.update(kw) 
105   
106          return self.actual_widget(dbobj, self.dbproperty, **params) 
107   
108 -    class actual_widget: 
109 -        def __init__(self, dbobj, dbproperty, **kw): 
110              self.dbobj = dbobj 
111              self.dbproperty = dbproperty 
112               
113              for name, value in kw.items(): 
114                  setattr(self, name, value) 
115   
116                   
117   
118  ###################################################################### 
119  ## Views 
120  ###################################################################### 
121   
122 -class view: 
123 -    def __init__(self, dbobj=None, result=None): 
124          self.dbobj = dbobj 
125          if dbobj is not None: self.dbclass = dbobj.__class__ 
126               
127          self.result = result 
128          if result is not None: self.dbclass = result.dbclass 
129   
130          if (dbobj is None and result is None) or \ 
131             (dbobj is not None and result is not None): 
132              raise ValueError("A view must be initialized either with " + \ 
133                               "dbobj XOR result set to an appropriate value") 
134   
135          if self.dbobj is not None: 
136              self._ds = dbobj.__ds__() 
137          else: 
138              self._ds = result.ds 
139   
140 -    def ds(self): 
141          if not hasattr(self, "_ds"): 
142              raise Exception("View without a constructor! You forgot to call" 
143                              " view.__init__() in one of your views, so the" 
144                              " view knows of no ds. It simply won't work" 
145                              " that way ;-") 
146               
147          if self._ds is None: 
148              if self.dbobj is not None: 
149                  self._ds = self.dbobj.__ds__() 
150              else: 
151                  self._ds = self.result.ds 
152   
153                   
154              if self._ds is None: 
155                  raise ValueError("Plase make sure any dbobj you use with a  "+\ 
156                                   "view knows a datasource (use the __ds "+ \ 
157                                   "param to its constructor!)") 
158          else: 
159              return self._ds 
160   
161   
162 -class view_spec: 
163      """ 
164      The view spec class provides a mechanism to lazily load views at runtime. 
165      This avoids infinite loops in complex module hierarchies that have 
166      seperate modules for dbclasses and views. Defining you dbclass like this:: 
167   
168         class font(dbobject): 
169             id = serial() 
170             ps_name = text() 
171             user_name = Unicode() 
172   
173             preview = view_spec('myproject.views.font') 
174   
175      will cause the myproject.views.font module to be loaded. It must contain 
176      a class names preview which inherits from orm2.ui.view. This class will be 
177      instantiated and put into the font dbobject on initialization. 
178      """ 
179 -    def __init__(self, module_name): 
180          self.module_name = module_name 
181   
182 -    def import_(self, class_name): 
183          if sys.modules.has_key(self.module_name): 
184              module = sys.modules[self.module_name] 
185              if debug.debug.verbose: 
186                  reload(module) 
187          else: 
188              complete_module_name = self.module_name 
189              module_path = split(complete_module_name, ".") 
190              module_name = module_path[-1] 
191              module_path = join(module_path, ".") 
192           
193              module = __import__(module_path, 
194                                  globals(), locals(), 
195                                  module_name) 
196   
197              sys.modules[self.module_name] = module 
198   
199          return getattr(module, class_name) 
200   
201   
202   
203  # Local variables: 
204  # mode: python 
205  # ispell-local-dictionary: "english" 
206  # End: 
207