--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/app/soc/views/helper/forms.py Fri Oct 03 23:59:49 2008 +0000
@@ -0,0 +1,172 @@
+#!/usr/bin/python2.5
+#
+# Copyright 2008 the Melange authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Helpers used to display various views that are forms.
+"""
+
+__authors__ = [
+ '"Chen Lunpeng" <forever.clp@gmail.com>',
+ '"Todd Larsen" <tlarsen@google.com>',
+ ]
+
+
+from google.appengine.ext.db import djangoforms
+
+from django import newforms as forms
+from django.utils import safestring
+
+
+class DbModelForm(djangoforms.ModelForm):
+ """Subclass of Django ModelForm that fixes some label and help_text issues.
+
+ The default behavior of ModelForm is to use the verbose_name in all
+ lowercase, capitalizing only the first character, as the displayed field
+ label. This class uses verbose_name unaltered as the visible field label
+ instead.
+
+ The Property classes used by the App Engine Datastore do not have a
+ help_text parameter to their constructor. In a Model class, a help_text
+ attribute *can* be added to the property after it is created, but the
+ help text will not be automatically passed along to the Django ModelForm.
+ This class detects the presence of a help_text attribute and adds it to
+ the corresponding form field object.
+
+ ugettext_lazy() proxies used for internationalization in the Model will
+ still work correctly with this new behavior, as long as the original
+ strings are used as the translation keys.
+ """
+
+ def __init__(self, *args, **kwargs):
+ """Fixes label and help_text issues after parent initialization.
+
+ Args:
+ *args, **kwargs: passed through to parent __init__() constructor
+ """
+ super(DbModelForm, self).__init__(*args, **kwargs)
+
+ for field_name in self.fields.iterkeys():
+ # Since fields can be added only to the ModelForm subclass, check to
+ # see if the Model has a corresponding field first.
+ if hasattr(self.Meta.model, field_name):
+ model_prop = getattr(self.Meta.model, field_name)
+
+ # Check if the Model property defined verbose_name, and copy that
+ # verbatim to the corresponding field label.
+ if hasattr(model_prop, 'verbose_name'):
+ self.fields[field_name].label = model_prop.verbose_name
+
+ # Check if the Model property added help_text, and copy that verbatim
+ # to the corresponding field help_text.
+ if hasattr(model_prop, 'help_text'):
+ self.fields[field_name].help_text = model_prop.help_text
+
+
+class SelectQueryArgForm(forms.Form):
+ """URL query argument change control implemented as a Django form.
+ """
+
+ ONCHANGE_JAVASCRIPT_FMT = '''
+<script type="text/javascript">
+ function changeArg_%(arg_name)s(item)
+ {
+ var idx=item.selectedIndex;
+ item.selected=true;
+ var value=item.value
+ var url = location.href
+ var reg = /%(arg_name)s=\d+/
+ url = url.replace(reg, "%(arg_name)s="+value)
+ if(url.match(reg))
+ document.location.href = url
+ else
+ document.location.href = "%(page_path)s?%(arg_name)s="+value;
+ }
+</script>
+'''
+
+ def __init__(self, page_path, arg_name, choices, field_name,
+ *form_args, **form_kwargs):
+ """
+ Args:
+ page_path: (usually request.path)
+ arg_name: the URL query parameter that determines which choice is
+ selected in the selection control
+ choices: list (or tuple) of value/label string two-tuples, for example:
+ (('10', '10 items per page'), ('25', '25 items per page'))
+ field_name: name of the selection field in the form
+ *form_args: positional arguments passed on to the Form base
+ class __init__()
+ *form_kwargs: keyword arguments passed on to the Form base
+ class __init__()
+ """
+ super(SelectQueryArgForm, self).__init__(*form_args, **form_kwargs)
+
+ self._script = safestring.mark_safe(self.ONCHANGE_JAVASCRIPT_FMT % {
+ 'arg_name': arg_name, 'page_path': page_path,})
+
+ onchange_js_call = 'changeArg_%s(this)' % arg_name
+
+ self.fields[field_name] = forms.ChoiceField(
+ label='', choices=choices,
+ widget=forms.widgets.Select(attrs={'onchange': onchange_js_call}))
+
+ def as_table(self):
+ """Returns form rendered as HTML <tr> rows -- with no <table></table>.
+
+ Prepends <script> section with onchange function included.
+ """
+ return self._script + super(SelectQueryArgForm, self).as_table()
+
+ def as_ul(self):
+ """Returns form rendered as HTML <li> list items -- with no <ul></ul>.
+
+ Prepends <script> section with onchange function included.
+ """
+ return self._script + super(SelectQueryArgForm, self).as_ul()
+
+ def as_p(self):
+ """Returns form rendered as HTML <p> paragraphs.
+
+ Prepends <script> section with onchange function included.
+ """
+ return self._script + super(SelectQueryArgForm, self).as_p()
+
+
+DEF_SELECT_QUERY_ARG_FIELD_NAME_FMT = 'select_query_arg_%(arg_name)s'
+
+def makeSelectQueryArgForm(
+ request, arg_name, initial_value, choices,
+ field_name_fmt=DEF_SELECT_QUERY_ARG_FIELD_NAME_FMT):
+ """Wrapper that creates a customized SelectQueryArgForm.
+
+ Args:
+ request: the standard Django HTTP request object
+ arg_name: the URL query parameter that determines which choice is
+ selected in the selection control
+ initial_value: the initial value of the selection control
+ choices: list (or tuple) of value/label string two-tuples, for example:
+ (('10', '10 items per page'), ('25', '25 items per page'))
+ field_name_fmt: optional form field name format string; default is
+ DEF_SELECT_QUERY_ARG_FIELD_NAME_FMT; contains these named format
+ specifiers:
+ arg_name: replaced with the arg_name argument
+
+ Returns:
+ a Django form implementing a query argument selection control, for
+ insertion into a template
+ """
+ field_name = field_name_fmt % {'arg_name': arg_name}
+ return SelectQueryArgForm(request.path, arg_name, choices, field_name,
+ initial={field_name: initial_value})