How to edit inline objects with reverse generic relation in Admin Panel?

Question

I would like to be able to add inline Image objects to Gallery in Admin (as I try it in admin.py below). Problem is that Image model doesn't have content_type field. It raises exception. I would like to do the same with Videos objects. Here are my models.py and admin.py and more description below

My models.py

# -*- coding: utf-8 -*-

# Create your models here.
from apps.util import models
from django.contrib.contenttypes.models import ContentType
from django.contrib.contenttypes import generic
from django.utils.translation import ugettext_lazy as _


class Image(models.Model):
    """

    """
    title = models.CharField(_('Title'), max_length=255)
    image = models.ImageField(upload_to="images")
    pub_date = models.DateTimeField(_('Date published'))           

    def __unicode__(self):
        return self.title

class Video(models.Model):

    title = models.CharField(_('Title'), max_length=255)
    video = models.FileField(upload_to="videos")
    pub_date = models.DateTimeField(_('Date published'))

    def __unicode__(self):
        return self.title 

class Gallery(models.Model):

    title = models.CharField(_('Title'), max_length=255)
    pub_date = models.DateTimeField(_('Date published'))

    def __unicode__(self):
        return self.title

class GalleryItem(models.Model):
    gallery = models.ForeignKey(Gallery)
    content_type = models.ForeignKey(ContentType)
    object_id = models.PositiveIntegerField()
    content_object = generic.GenericForeignKey('content_type', 'object_id')

    def __unicode__(self):
        return str(self.object_id)  

My admin.py

from django.contrib import admin
from apps.webmachinist.media.models import *
from apps.webmachinist.portfolio.models import *
from django.contrib.contenttypes import generic

class GalleryInline(generic.GenericTabularInline):
    model = Image

class GalleryAdmin(admin.ModelAdmin):
    inlines = [
        GalleryInline,
    ]

admin.site.register(Image)
admin.site.register(Video)
admin.site.register(Gallery, GalleryAdmin)
admin.site.register(GalleryItem)
admin.site.register(PortfolioEntry)

I can do it easily in reverse way: to add Gallery to an Image, like that:

class GalleryInline(generic.GenericTabularInline):
    model = GalleryItem

class GalleryAdmin(admin.ModelAdmin):
    inlines = [
        GalleryInline,
    ]

admin.site.register(Image, GalleryAdmin)

Then I can choose by Gallery title, though inline is for GalleryItems But it's not what I want. I just want to add Images to Galleries (and later Videos) not Galleries to Images.

Can it be done easily?

Answer 1

You shouldn't be inlining Image, but rather GalleryItem. Then from each GalleryItem you can associate it with whatever through it's generic foreign key.