将“另存为”按钮添加到Django异物编辑弹出窗口

Question

In Django we have save_as parameter for ModelAdmin, that enables "Save as new" button on the admin's site edit page of some object.

But when the object (Model1 instance) is in relations with other model (Model2) by default, and I want to edit Model2 instance in following way: take default for the current relation (depends on Model2 instance fields) Model1 instance and edit some of its fields, I click edit button and the popup appears, where I can change some fields, but can't save that object as new, so I have 2 option: corrupt the default object or copy-paste each field of that related object into "Add new" popup.

I want to add "Save as new" button into Edit popup.

I have found, that adding hidden input with name="_saveasnew" and value=1 is actually does save another model, but how to add it among with special button?

Also, there is special block on that button for popup window, as I see: https://github.com/django/django/blob/1.8/django/contrib/admin/templatetags/admin_modify.py#L39 (yes, we use Django 1.8 :() What is the best solution: edit the template or edit the tag itself?

Answer 1

The right solution is to use your own submit_row template tag for popup window, to do it, you have to override admin/change_form.html template's blocks: submit_buttons_top and submit_buttons_bottom :

{% extends "admin/change_form.html" %}
{% load YOUR_TEMPLATE_TAGS %}

{% block submit_buttons_top %}{% YOUR_SUBMIT_ROW_TAG %}{% endblock %}

{% block submit_buttons_bottom %}{% YOUR_SUBMIT_ROW_TAG %}{% endblock %}

Main difference in code of new submit_row tag is changed context key: 'show_save_as_new': change and save_as,

Code of YOUR_TEMPLATE_TAGS.py could look something like this:

from django import template

register = template.Library()


@register.inclusion_tag('admin/submit_line.html', takes_context=True)
def YOUR_SUBMIT_ROW_TAG(context):
    """
    Displays the row of buttons for delete and save.

    HINT: override of default django `submit_row` tag, changes:
          `save as new` button is displayed for popup.
    """
    opts = context['opts']
    change = context['change']
    is_popup = context['is_popup']
    save_as = context['save_as']
    new_context = {
        'opts': opts,
        'show_delete_link': (
            not is_popup and context['has_delete_permission'] and
            change and context.get('show_delete', True)
        ),
        'show_save_as_new': change and save_as,
        'show_save_and_add_another': (
            context['has_add_permission'] and not is_popup and
            (not save_as or context['add'])
        ),
        'show_save_and_continue': not is_popup and context['has_change_permission'],
        'is_popup': is_popup,
        'show_save': True,
        'preserved_filters': context.get('preserved_filters'),
    }
    if context.get('original') is not None:
        new_context['original'] = context['original']
    return new_context