How do I add a link from the Django admin page of one object to the admin page of a related object

Question

I have one model, post (not its real name) that is both an inline on the blog admin page, and also has its own admin page.

 The reason it can't just be inline is that it has models with foreign keys to it that only make sense when edited with it, and it only makes sense when edited with blog.

For the post admin page, I changed part of "fieldset.html" from:

{% if field.is_readonly %}
    <p>{{ field.contents }}</p>
{% else %}
    {{ field.field }}
{% endif %}

to

{% if field.is_readonly %}
    <p>{{ field.contents }}</p>
{% else %}
    {% ifequal field.field.name "blog" %}
        <p>{{ field.field.form.instance.blog_link|safe }}</p>
    {% else %}
        {{ field.field }}
    {% endifequal %}
{% endif %}

to create a link to the blog admin page, where blog_link is a method on the model:

def blog_link(self):
      return '<a href="%s">%s</a>' % (reverse("admin:myblog_blog_change",  
                                        args=(self.blog.id,)), escape(self.blog))

I couldn't find the id of the blog instance anywhere outside field.field.form.instance.

On the blog admin page, where post is inline, I modified part of "stacked.html" from:

<h3><b>{{ inline_admin_formset.opts.verbose_name|title }}:</b>&nbsp;
<span class="inline_label">{% if inline_admin_form.original %}
    {{ inline_admin_form.original }}
{% else %}#{{ forloop.counter }}{% endif %}</span>

to

<h3><b>{{ inline_admin_formset.opts.verbose_name|title }}:</b>&nbsp;
<span class="inline_label">{% if inline_admin_form.original %}
    {% ifequal inline_admin_formset.opts.verbose_name "post" %}
    <a href="/admin/myblog/post/{{ inline_admin_form.pk_field.field.value }}/">
            {{ inline_admin_form.original }}</a>
{% else %}{{ inline_admin_form.original }}{% endifequal %}
{% else %}#{{ forloop.counter }}{% endif %}</span>

to create a link to the post admin page since here I was able to find the id stored in the foreign key field.

How to solve this?

Answer 1

Hello @kartik,

Set show_change_link to True (False by default) in your inline model, so that inline objects have a link to their change form (where they can have their own inlines).

from django.contrib import admin

class PostInline(admin.StackedInline):
    model = Post
    show_change_link = True
    ...

class BlogAdmin(admin.ModelAdmin):
    inlines = [PostInline]
    ...

class ImageInline(admin.StackedInline):
    # Assume Image model has foreign key to Post
    model = Image
    show_change_link = True
    ...

class PostAdmin(admin.ModelAdmin):
    inlines = [ImageInline]
    ...

admin.site.register(Blog, BlogAdmin)
admin.site.register(Post, PostAdmin)

Hope this helps!!