from django.newforms import *
from django.newforms.widgets import flatatt
def form_decorator(fields = {}, attrs = {}, widgets = {},
labels = {}, choices = {}):
"""
This function helps to add overrides when creating forms from models/instances.
Pass in dictionary of fields to override certain fields altogether, otherwise
add widgets or labels as desired.
For example:
class Project(models.Model):
name = models.CharField(maxlength = 100)
description = models.TextField()
owner = models.ForeignKey(User)
project_fields = dict(
owner = None
)
project_widgets = dict(
name = forms.TextInput({"size":40}),
description = forms.Textarea({"rows":5, "cols":40}))
project_labels = dict(
name = "Enter your project name here"
)
callback = form_decorator(project_fields, project_widgets, project_labels)
project_form = forms.form_for_model(Project, formfield_callback = callback)
This saves having to redefine whole fields for example just to change a widget
setting or label.
"""
def formfields_callback(f, **kw):
if f.name in fields:
# replace field altogether
field = fields[f.name]
f.initial = kw.pop("initial", None)
return field
if f.name in widgets:
kw["widget"] = widgets[f.name]
if f.name in attrs:
widget = kw.pop("widget", f.formfield().widget)
if widget :
widget.attrs.update(attrs[f.name])
kw["widget"] = widget
if f.name in labels:
kw["label"] = labels[f.name]
if f.name in choices:
choice_set = choices[f.name]
if callable(choice_set) : choice_set = choice_set()
kw["choices"] = choice_set
return f.formfield(**kw)
return formfields_callback
class ChainSelectWidget(Widget):
#This widget uses javascript to build Chain Selects to
#narrow down ForeignKey object types in an intuitive manner.
#It is especially useful when the __str__ of the object direct foreign
#key isn't necessarily unique, and the parent model of it needs
#to be looked at.
#This code uses the Chained Select javascript written by
#Xin Yang (http://www.yxscripts.com/)
#This widget must be used on custom views. I had a VERY hard time
#trying to get it registered into the form_for_model and
#form_for_instance helper functions.
#example:
###models.py###
#class A(models.Model):
# name=models.CharField()
#class B(models.Model):
# name=models.CharField()
# to_A = models.ForeignKey(A)
#class C(models.Model):
# name=models.CharField()
# to_B = models.ForeignKey(B)
###views.py###
#def test(request):
# import A,B,C
# from CustomWidgets import *
# from django.newforms import form_for_model
# from django.shortcuts import render_to_response
# widget_overwrite=dict(to_B=ChainSelectWidget(order=[(A, 'name'), (B, 'name'), (C, 'name')]))
# callback=form_decorator(widgets=widget_overwrite)
# modified_form=form_for_model(C, formfield_callback=callback)()
# return render_to_response('path/to/template.html', {'form': modified_form})
###template.html###
#...
#<head>
#<script language="javascript" src="path/to/chainedselects.js"></script>
#</head>
#...
#<form>
#{% for field in form %}
#{{field.label}}: {{field}}
#{% endfor %}
#...
def __init__(self, attrs=None, order=[]):
#Order is a list of model objects that define the chain select tree
#it is a list of tuples. The first value is the model object, the second
#value the field to order by
#eg:
# order=[(A, 'name'), (B, 'name'), (C, 'name')]
self.attrs = attrs or {}
self.html = ''
self.order = list(order)
def _buildjs(self, current=None, backtrail=''):
if current == None:
current = self.order[0][0].objects.all().order_by(self.order[0][1])
if len(current) == 0:
return ''
self.html +='addOption("%s", "---------", "", 1);\n'%(backtrail)
if current[0]._meta.module_name == self.order[-1][0]._meta.module_name:
for end in current:
self.html += 'addList("%s", "%s", "%s");\n' % (backtrail, str(end), end._get_pk_val())
else:
for (base_model, order_set_by) in self.order:
if base_model._meta.module_name == current[0]._meta.module_name:
get_set = self.order[self.order.index((base_model, order_set_by))+1][0]._meta.module_name
for entry in current:
self.html += 'addList("%s", "%s", "", "%s__%s");\n' % (backtrail, str(entry), backtrail, str(entry))
self._buildjs(backtrail='%s__%s'%(backtrail, str(entry)), current=getattr(entry, '%s_set'%(get_set)).all().order_by(order_set_by))
def render(self, name, value, attrs=None):
self.html += '<table>\n'
for entry in self.order:
self.html += '<tr><td align="right">%s:</td>\n' % entry[0]._meta.module_name.capitalize()
if entry[0] == self.order[-1][0]:
final_attrs = self.build_attrs(attrs, name=name)
self.html += '<td><select %s></select></td></tr>\n' % flatatt(final_attrs)
else:
self.html += '<td><select name="chain_to_%s__%s"></select></td></tr>\n' % (name, entry[0]._meta.module_name)
self.html += '</table>\n'
self.html += '<script language="javascript">\n'
self.html += 'var disable_empty_list=true;\n'
self.html += 'var newwindow=0;\n'
self.html += 'addListGroup("%s", "%s__%s");\n'%(name, name, self.order[0][0].objects.all()[0]._meta.module_name)
self._buildjs(current=None, backtrail='%s__%s'%(name, self.order[0][0].objects.all()[0]._meta.module_name))
self.html += '</script>\n'
self.html += '<script language="javascript">\n'
self.html += 'initListGroup("%s", '%name
for entry in self.order:
if entry[0] == self.order[-1][0]:
self.html += 'document.forms[0].%s, ' % name
else:
self.html += 'document.forms[0].chain_to_%s__%s, ' % (name, entry[0]._meta.module_name)
self.html += '"savestate");\n'
self.html += '</script>\n'
return u'%s' % self.html