Question

Standard example:

class Author(models.Model):
  name = models.CharField(max_length=100)

class Book(models.Model):
  title = models.CharField(max_length=100)
  author = models.ForeignKey(Author)
  #... Many other fields ...

I’d like to edit the Books from the Author change page.
I tried with InlineModelAdmin but since Book has many fields, it’s not easy to edit.
That’s why I tried to put links towards the children on the author/change template.

<ul>
  <li><a href="{% url admin:content_scribpart_add %}">Add a Book</a></li>
{% for book in original.book_set.all %}
  <li><a href="{% url admin:myapp_book_change book.id %}">Edit {{ book }}</a></li>
{% endfor %}
</ul>

But there are several questions

• How can I prepopulate the related Author id in the Book form
• How can I make the Save button to go back to the related Author
• Am I on right track ?

Answer 1

Yes, sure.

1. Append author primary key as GET parameter to your url:

   <ul>
     <li><a href="{% url admin:content_scribpart_add %}?author={{ object_id }}">Add a Book</a></li>
   {% for book in original.book_set.all %}
     <li><a href="{% url admin:myapp_book_change book.id %}?author={{ object_id }}">Edit {{ book }}</a></li>
   {% endfor %}
   </ul>
   

2. Modify the corresponding ModealAdmin for book, override response_add() and response_change(). Note that we also override formfield_for_forein_key in order to pre-populate author field:

   from django.http import HttpResponseRedirect
   from django.core.urlresolvers import reverse
   
   class BookAdmin(admin.ModelAdmin):
   
       def formfield_for_foreignkey(self, db_field, request, **kwargs):
           if db_field.name == "author":                    
               try:
                   author_pk = int(request.GET.get('author', ''),) 
               except ValueError:           
                   pass
               else:
                   kwargs["initial"] = Author.objects.get(pk=author_pk)
   
           return super(BookAdmin, self).formfield_for_foreignkey(db_field, request, **kwargs)
   
       def response_add(self, request, obj, post_url_continue=None):
           return HttpResponseRedirect(reverse('admin:myapp_author_change', args=(obj.author.pk,))
           )
   
       def response_change(self, request, obj, post_url_continue=None):
           return HttpResponseRedirect(reverse('admin:myapp_author_change', args=(obj.author.pk,))
           )