django-multiselectfield/multiselectfield/forms/fields.py

# -*- coding: utf-8 -*-
# Copyright (c) 2012 by Pablo Martín <goinnn@gmail.com>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with this programe.  If not, see <http://www.gnu.org/licenses/>.

from django import forms

from ..utils import get_max_length
from ..validators import MaxValueMultiFieldValidator, MinChoicesValidator, MaxChoicesValidator


class MultiSelectFormField(forms.MultipleChoiceField):
    widget = forms.CheckboxSelectMultiple

    def __init__(self, *args, **kwargs):
        self.min_choices = kwargs.pop('min_choices', None)
        self.max_choices = kwargs.pop('max_choices', None)
        self.max_length = kwargs.pop('max_length', None)
        super(MultiSelectFormField, self).__init__(*args, **kwargs)
        self.max_length = get_max_length(self.choices, self.max_length)
        self.validators.append(MaxValueMultiFieldValidator(self.max_length))
        if self.max_choices is not None:
            self.validators.append(MaxChoicesValidator(self.max_choices))
        if self.min_choices is not None:
            self.validators.append(MinChoicesValidator(self.min_choices))