Actions¶
Actions are defined to work on a single view type. Currently, actions are only implemented against the ModelListView
. This view contains the default DeleteSelectedAction
method, which in end functionality mirrors django.contrib.admin.delete_selected
.
However, under the hood, django-admin2’s actions work very differently. Instead of functions with assigned attributes, they can either be functions or full fledged objects. Which means you can more easily extend them to suit your needs.
The documentation works off a simple set of models, as listed below:
# blog/models.py
from django.db import models
STATUS_CHOICES = (
('d', 'Draft'),
('p', 'Published'),
('w', 'Withdrawn'),
)
class Post(models.Model):
title = models.CharField(max_length=255)
body = models.TextField()
status = models.CharField(max_length=1, choices=STATUS_CHOICES)
def __unicode__(self):
return self.title
class Comment(models.Model):
post = models.ForeignKey(Post)
body = models.TextField()
def __unicode__(self):
return self.body
Writing List Actions¶
The basic workflow of Django’s admin is, in a nutshell, “select an object, then change it.” This works well for a majority of use cases. However, if you need to make the same change to many objects at once, this workflow can be quite tedious.
In these cases, Django’s admin lets you write and register “actions” – simple functions that get called with a list of objects selected on the change list page.
If you look at any change list in the admin, you’ll see this feature in action; Django ships with a “delete selected objects” action available to all models. Using our sample models, let’s pretend we wrote a blog article about Django and our mother put in a whole bunch of embarressing comments. Rather than cherry-pick the comments, we want to delete the whole batch.
In our blog/admin.py module we write:
from djadmin2.actions import BaseListAction
from djadmin2.site import djadmin2_site
from djadmin2.types import ModelAdmin2
from .models import Post, Comment
class DeleteAllComments(BaseListAction):
description = 'Delete selected items'
default_template_name = 'actions/delete_all_comments_confirmation.html'
success_message = 'Successfully deleted %d %s' # first argument - items count, second - verbose_name[_plural]
def process_queryset(self):
"""Every action must provide this method"""
self.get_queryset().delete()
def custom_function_action(request, queryset):
print(queryset.count())
custom_function_action.description = 'Do other action'
class PostAdmin(ModelAdmin2):
actions = [DeleteAllComments, custom_function_action]
djadmin2_site.register(Post, PostAdmin)
djadmin2_site.register(Comment)
Warning
The “delete selected objects” action uses QuerySet.delete() for efficiency reasons, which has an important caveat: your model’s delete() method will not be called.
If you wish to override this behavior, simply write a custom action which accomplishes deletion in your preferred manner – for example, by calling Model.delete()
for each of the selected items.
For more background on bulk deletion, see the documentation on object deletion.
Read on to find out how to add your own actions to this list.