from django import forms
from django.db import models
from django.utils.text import capfirst
from django.core import exceptions
class MultiSelectFormField(forms.MultipleChoiceField):
widget = forms.CheckboxSelectMultiple
def __init__(self,*args,**kwargs):
self.max_choices = kwargs.pop('max_choices',0)
super(MultiSelectFormField,self).__init__(*args,**kwargs)
def clean(self,value):
if not value and self.required:
raise forms.ValidationError(self.error_messages['required'])
# if value and self.max_choices and len(value) > self.max_choices:
# raise forms.ValidationError('You must select a maximum of %s choice%s.'
# % (apnumber(self.max_choices),pluralize(self.max_choices)))
return value
class MultiSelectField(models.Field):
__metaclass__ = models.SubfieldBase
def get_internal_type(self):
return "CharField"
def get_choices_default(self):
return self.get_choices(include_blank=False)
def _get_FIELD_display(self,field):
value = getattr(self,field.attname)
choicedict = dict(field.choices)
def formfield(self,**kwargs):
# don't call super,as that overrides default widget if it has choices
defaults = {'required': not self.blank,'label': capfirst(self.verbose_name),
'help_text': self.help_text,'choices': self.choices}
if self.has_default():
defaults['initial'] = self.get_default()
defaults.update(kwargs)
return MultiSelectFormField(**defaults)
def get_prep_value(self,value):
return value
def get_db_prep_value(self,value,connection=None,prepared=False):
if isinstance(value,basestring):
return value
elif isinstance(value,list):
return ",".join(value)
def to_python(self,value):
if value is not None:
return value if isinstance(value,list) else value.split(',')
return ''
def contribute_to_class(self,cls,name):
super(MultiSelectField,self).contribute_to_class(cls,name)
if self.choices:
func = lambda self,fieldname = name,choicedict = dict(self.choices): ",".join([choicedict.get(value,value) for value in getattr(self,fieldname)])
setattr(cls,'get_%s_display' % self.name,func)
def validate(self,model_instance):
arr_choices = self.get_choices_selected(self.get_choices_default())
for opt_select in value:
if (int(opt_select) not in arr_choices): # the int() here is for comparing with integer choices
raise exceptions.ValidationError(self.error_messages['invalid_choice'] % value)
return
def get_choices_selected(self,arr_choices=''):
if not arr_choices:
return False
list = []
for choice_selected in arr_choices:
list.append(choice_selected[0])
return list
def value_to_string(self,obj):
value = self._get_val_from_obj(obj)
return self.get_db_prep_value(value)
