Autocompletion for GenericForeignKey

Model example

Consider such a model:

from django.contrib.contenttypes.fields import GenericForeignKey
from django.db import models


class TestModel(models.Model):
    name = models.CharField(max_length=200)
    language = models.CharField(max_length=200)

    content_type = models.ForeignKey(
        'contenttypes.ContentType',
        null=True,
        blank=True,
        editable=False,
    )

    object_id = models.PositiveIntegerField(
        null=True,
        blank=True,
        editable=False,
    )

    location = GenericForeignKey('content_type', 'object_id')

    def __str__(self):
        return self.name

Form example

To enable the use of automatic views we need to add ‘dal_queryset_sequence’
to INSTALLED_APPS.

First, we can’t use Django’s ModelForm because it doesn’t support non-editable fields, which GenericForeignKey is. Instead, we’ll use dal.forms.FutureModelForm.

Then we need to add the dal_select2_queryset_sequence.fields.Select2GenericForeignKeyModelField field, with model_choice as keyword: this is a list of tuple, with the models you want in the autocompletion and the validation, and the value of the attribute of the model you want to query in the widget searchbox. Optionally, you can forward an existing field in the form to filter an attribute of the model, by adding a list of tuple containing the field to forward and the value to filter. In this example, the text inserted in the language field will filter the country models by their ‘spoken_language’ attribute.

Result:

from dal import autocomplete

class TestForm(autocomplete.FutureModelForm):

    location = autocomplete.Select2GenericForeignKeyModelField(
        # Model with values to filter, linked with the name field
        model_choice=[(Country, 'country_code', [('language', 'spoken_language'),]),
                      (City, 'name')],
    )

    class Meta:
        model = TestModel

If you want to use your own widgets and views, assuming the widget takes an url as argument and the view takes a queryset in its “as_view()” method, you can use GenericForeignKeyModelField:

from dal import autocomplete

class TestForm(autocomplete.FutureModelForm):

    location = autocomplete.GenericForeignKeyModelField(
        model_choice=[(Country,), (City,)],  # Models
        widget=autocomplete.QuerySetSequenceSelect2,
        view=autocomplete.Select2QuerySetSequenceView,
    )

    class Meta:
        model = TestModel

In this example, we took QuerySetSequenceSelect2 as the custom widget and Select2QuerySetSequenceView.

Register the view for the form

In url.py:

from .forms import TestForm

urlpatterns = [...]  # your regular url patterns
urlpatterns.extend(TestForm.as_urls())

It will enable the search box to query and filter the results