This application adds a new widget into your forms. This widget changes a behaviour of a Select widget linking it to other select field.
For instance, let you have two select fields on a form: 'categories' and 'items'. Usually, visitors want to choose a category and then take an item of this category. This widget helps you implement this functionality.
Hint: Use a virtual environment!
To install this package run:
pip install -e git+git://github.com/RaD/django-chained-selects#egg=django-chunks
Add the following line into INSTALLED_APPS in settings.py:
'chained_selects',
Add the following line into main urls.py:
url(r'^chained/', include('chained_selects.urls')),
We have following models:
class Category(models.Model):
title = models.CharField(max_length=64)
class Item(models.Model):
category = models.ForeignKey(Category)
title = models.CharField(max_length=64)
is_present = models.BooleanField(default=False)
You have to implement a model method that will return a queryset. Use this method to filter a resulting queryset. You may use any name for this method. For instance:
class Category(models.Model):
...
def chained_relation(self):
return self.item_set.filter(is_present=True)
Create a form:
from chained_selects.widgets import ChainedSelectWidget
class TestForm(forms.Form):
category = forms.ModelChoiceField(queryset=Category.objects.all())
item = forms.ModelChoiceField(queryset=Item.objects.all())
def __init__(self, *args, **kwargs):
super(TestForm, self).__init__(*args, **kwargs)
if 0 == len(self.data):
# clear queryset if we just show a form
self.fields['item'].queryset = Item.objects.none()
# assign a widget to second select field
self.fields['item'].widget = ChainedSelectWidget(
parent_name='category', # the name of parent field
app_name='app_name', # the name of model's application
model_name='category', # the name of a model with the method
method_name='chained_relation', # the name of queryset method
)
Then use this form as usual.