Django Admin nested inline

Question:

I need a nested django admin inline,
which I can include the date field inlines in an other inline like below.

I have the models below:

class Person(models.Model):
     name = models.CharField(max_length=200)
     id_no = models.IntegerField()

class Certificate(models.Model):
     cerfificate_no = models.CharField(max_length=200)
     certificate_date = models.DateField(max_length=100)
     person = models.ForeignKey(Person)
     training = models.CharField(max_length=200)

class Training_Date(models.Model):
      date = models.DateField()
      certificate = models.ForeignKey(Certificate)

And, the admin below:

class CertificateInline(admin.StackedInline):
    model = Certificate

class PersonAdmin(admin.ModelAdmin):
     inlines = [CertificateInline,]
admin.site.register(Person,PersonAdmin)

But, I need to include the Training_Date model as inline which is part of Certificate admin inline.

Any idea?

Asked By: tuna

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Source

Answers:

AFAIK, you can’t have a second level of inlines in the default Django admin.

The Django admin is just a normal Django application, so nothing prevents you from implementing a second level of nested forms, but IMHO it would be a kind of convoluted design to implement. Perhaps that is why there is no provision for it.

Answered By: Paulo Scardine

There has been some movement in https://code.djangoproject.com/ticket/9025 recently, but I wouldn’t hold my breath.

One common way around this is to link to an admin between first and second (or second and third) level by having both a ModelAdmin and an Inline for the same model:

Give Certificate a ModelAdmin with TrainingDate as an inline. Set show_change_link = True for CertificateInline so you can click on an inline to go to its ModelAdmin change form.

admin.py:

# Certificate change form has training dates as inline

class TrainingDateInline(admin.StackedInline):
    model = TrainingDate

class CertificateAdmin(admin.ModelAdmin):
    inlines = [TrainingDateInline,]
admin.site.register(Certificate ,CertificateAdmin)

# Person has Certificates inline but rather
# than nesting inlines (not possible), shows a link to
# its own ModelAdmin's change form, for accessing TrainingDates:

class CertificateLinkInline(admin.TabularInline):
    model = Certificate
    # Whichever fields you want: (I usually use only a couple
    # needed to identify the entry)
    fields = ('cerfificate_no', 'certificate_date')
    # Django 1.8 introduced this, no need to make your own link
    show_change_link = True

class PersonAdmin(admin.ModelAdmin):
    inlines = [CertificateLinkInline,]
admin.site.register(Person, PersonAdmin)
Answered By: Danny W. Adair

More universal solution

from django.utils.safestring import mark_safe
from django.urls import reverse

class EditLinkToInlineObject(object):
    def edit_link(self, instance):
        url = reverse('admin:%s_%s_change' % (
            instance._meta.app_label,  instance._meta.model_name),  args=[instance.pk] )
        if instance.pk:
            return mark_safe(u'<a href="{u}">edit</a>'.format(u=url))
        else:
            return ''

class MyModelInline(EditLinkToInlineObject, admin.TabularInline):
    model = MyModel
    readonly_fields = ('edit_link', )

class MySecondModelAdmin(admin.ModelAdmin):
    inlines = (MyModelInline, )

admin.site.register(MyModel)
admin.site.register(MySecondModel, MySecondModelAdmin)
Answered By: bigzbig
pip install django-nested-inline

This package should do what you need.

Answered By: s-block

Nested inlines are provided at:
https://github.com/BertrandBordage/django-super-inlines/

pip install django-super-inlines
Answered By: Rick Westera

I used the solution provided by @bigzbig (thank you).

I also wanted to go back to the first list page once changes had been saved so added:

class MyModelInline(EditLinkToInlineObject, admin.TabularInline):
    model = MyModel
    readonly_fields = ('edit_link', )

    def response_post_save_change(self, request, obj):
        my_second_model_id = MyModel.objects.get(pk=obj.pk).my_second_model_id
        return redirect("/admin/mysite/mysecondmodel/%s/change/" % (my_second_model_id))
Answered By: appdev epiccycles

A more up to date solution (february 2021) is to use the show_change_link config variable: https://docs.djangoproject.com/en/3.1/ref/contrib/admin/#django.contrib.admin.InlineModelAdmin.show_change_link

This does exactly the same as the EditLinkToInlineObject proposed in solutions above, but is less code and is probably well tested by Django Developers

You would just have to define show_change_link=True in each one of your inlines

UPDATE (January 25th, 2022):
Here’s the updated link in the docs (Django 4.0): https://docs.djangoproject.com/en/4.0/ref/contrib/admin/#django.contrib.admin.InlineModelAdmin.show_change_link

Answered By: Daniel González Fernández

Use django-nested-admin which is the best package to do nested inlines.

First, install "django-nested-admin":

pip install django-nested-admin

Then, add "nested_admin" to "INSTALLED_APPS" in "settings.py":

# "settings.py"

INSTALLED_APPS = (
    # ...
    "nested_admin", # Here
)

Then, add "path(‘_nested_ad…" to "urlpatterns" in "urls.py":

# "urls.py"

from django.urls import include, path

urlpatterns = [
    # ...
    path('_nested_admin/', include('nested_admin.urls')), # Here
]

Finally, extend "NestedTabularInline" with "Training_DateInline()" and "CertificateInline()" classes and extend "NestedModelAdmin" with "PersonAdmin()" class in "admin.py" as shown below:

# "admin.py"

from .models import Training_Date, Certificate, Person
from nested_admin import NestedTabularInline, NestedModelAdmin

class Training_DateInline(NestedTabularInline):
    model = Training_Date

class CertificateInline(NestedTabularInline):
    model = Certificate
    inlines = [Training_DateInline]

@admin.register(Person)
class PersonAdmin(NestedModelAdmin):
    inlines = [CertificateInline]
Answered By: Kai – Kazuya Ito