django-gfklookupwidget

A widget to replace the object_id in a generic relation with a search link. It will open a popup to select a related item based on the content_type field. It supports inlines.

There's a screenshot. If you'd like to see it running, I created a Docker image.

docker run --publish 8000:8000 mqsoh/django-gfklookupwidget

You can access the admin at localhost:8000/admin and the credentials are admin/admin. If you create a new TaggedItem, you'll see the widget.

Installation

It's in the PyPi, so

pip install django-gfklookupwidget

...or...:

easy_install django-gfklookupwidget

Simple Usage

The easiest way is to use a field on your model. This is from the generic relation documentation. The GfkLookupField subclasses PositiveIntegerField and you can use it as the object_id.:

class TaggedItem(models.Model):
    tag = models.SlugField()
    content_type = models.ForeignKey(ContentType)
    object_id = gfklookupwidget.fields.GfkLookupField('content_type')
    content_object = generic.GenericForeignKey('content_type', 'object_id')

Complex Usage

The following is equivalent to the simple usage. The simple usage is convenient, but it confounds the admin and the data model. That doesn't bother me too much, but you're not me. Here is how you'd implement it with forms.:

class MyModelForm(django.forms.ModelForm):
    class Meta(object):
        model = myapp.models.MyModel
        widgets = {
            'object_id': gfklookupwidget.widgets.GfkLookupWidget(
                content_type_field_name='content_type',
                parent_field=myapp.models.MyModel._meta.get_field('content_type'),
            )
        }


class MyModelAdmin(django.contrib.admin.ModelAdmin):
    form = MyModelForm


django.contrib.admin.site.register(myapp.models.MyModel, MyModelAdmin)

And if you want to use it with an inline:

class MyModelInline(django.contrib.admin.StackedInline):
    model = core.models.MyModel
    extra = 0

    def formfield_for_dbfield(self, db_field, **kwargs):
        if db_field.name == 'object_id':
            kwargs['widget'] = gfklookupwidget.widgets.GfkLookupWidget(
                content_type_field_name='content_type',
                parent_field=myapp.models.MyModel._meta.get_field('content_type'),
            )

        return super(MyModelInline, self).formfield_for_dbfield(db_field, **kwargs)

Rationalization For This Code

After you've created a generic relation you're left with a text field for a foreign key ID. There's a really old ticket about it. There's a blog post that shows how to make a really nice one for yourself. I wasn't able to get it to work and didn't understand the implementation enough to figure out where to fix it. This is our solution.

License

Copyright (c) 2013, Mason Staugler

Permission to use, copy, modify, and/or distribute this software for any purpose with or without fee is hereby granted, provided that the above copyright notice and this permission notice appear in all copies.

THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.