| |
| from __future__ import unicode_literals |
|
|
| from django.db import models |
| from django.utils.encoding import force_text, python_2_unicode_compatible |
| from django.utils.six import string_types |
| from django.utils.translation import ugettext_lazy as _ |
|
|
| import likert_field.forms as forms |
|
|
|
|
| @python_2_unicode_compatible |
| class LikertField(models.IntegerField): |
| """A Likert field is simply stored as an IntegerField""" |
|
|
| description = _('Likert item field') |
|
|
| def __init__(self, *args, **kwargs): |
| """ |
| LikertField stores items with no answer as NULL |
| |
| By default responses are optional, so 'blank' is True |
| """ |
| if kwargs.get('null', True): |
| kwargs['null'] = True |
|
|
| if kwargs.get('blank', True): |
| kwargs['blank'] = True |
|
|
| super(LikertField, self).__init__(*args, **kwargs) |
|
|
| def __str__(self): |
| return "%s" % force_text(self.description) |
|
|
| def get_prep_value(self, value): |
| """ |
| Perform preliminary non-db specific value checks and conversions. |
| |
| The field expects a number as a string (ie. '2'). Unscored fields are |
| empty strings and are stored as NULL |
| """ |
| if value is None: |
| return None |
|
|
| if isinstance(value, string_types) and len(value) == 0: |
| return None |
|
|
| value = int(value) |
| if value < 0: |
| value = 0 |
|
|
| return value |
|
|
| def formfield(self, **kwargs): |
| defaults = { |
| 'min_value': 0, |
| 'form_class': forms.LikertFormField |
| } |
| defaults.update(kwargs) |
| return super(LikertField, self).formfield(**defaults) |
|
|
|
|
| try: |
| from south.modelsinspector import add_introspection_rules |
| except ImportError: |
| pass |
| else: |
| add_introspection_rules([], ["^likert_field\.models\.LikertField"]) |
|
|
