Django web 开发入门教程 （三）

Philosophy

Generating admin sites for your staff or clients to add, change and delete content is tedious work that doesn’t require much creativity. 
For that reason, Django entirely automates creation of admin interfaces for models.

Django was written in a newsroom environment, with a very clear separation between “content publishers” and the “public” site. Site 
managers use the system to add news stories, events, sports scores, etc., and that content is displayed on the public site. Django solves 
the problem of creating a unified interface for site administrators to edit content.

The admin isn’t intended to be used by site visitors. It’s for site managers.

Creating an admin user

First we’ll need to create a user who can login to the admin site. Run the following command:

$ python manage.py createsuperuser

Enter your desired username and press enter.

Username: admin

You will then be prompted for your desired email address:

Email address: admin@example.com

The final step is to enter your password. You will be asked to enter your password twice, the second time as a confirmation of the first.

Password: **********
Password (again): *********
Superuser created successfully.

Start the development server

The Django admin site is activated by default. Let’s start the development server and explore it.

Recall from Tutorial 1 that you start the development server like so:

$ python manage.py runserver

Now, open a Web browser and go to “/admin/” on your local domain – e.g., http://127.0.0.1:8000/admin/. You should see the admin’s login screen:

Doesn’t match what you see?

If at this point, instead of the above login page, you get an error page reporting something like:

ImportError at /admin/
cannot import name patterns
...

Enter the admin site

Now, try logging in with the superuser account you created in the previous step. You should see the Django admin index page:

Make the poll app modifiable in the admin

But where’s our poll app? It’s not displayed on the admin index page.

from django.contrib import admin

from .models import Question

admin.site.register(Question)

Explore the free admin functionality

Now that we’ve registered Question, Django knows that it should be displayed on the admin index page:

• The form is automatically generated from the Question model.
• The different model field types (DateTimeField, CharField) correspond to the appropriate HTML input widget. Each type of field knows how to display itself in the Django admin.
• Each DateTimeField gets free JavaScript shortcuts. Dates get a “Today” shortcut and calendar popup, and times get a “Now” shortcut and a convenient popup that lists commonly entered times.

• Save – Saves changes and returns to the change-list page for this type of object.
• Save and continue editing – Saves changes and reloads the admin page for this object.
• Save and add another – Saves changes and loads a new, blank form for this type of object.
• Delete – Displays a delete confirmation page.

Customize the admin form

Take a few minutes to marvel at all the code you didn’t have to write. By registering the Question model with

admin.site.register(Question), Django was able to construct a default form representation. Often, you’ll want to customize how the admin

form looks and works. You’ll do this by telling Django the options you want when you register the object.

Let’s see how this works by re-ordering the fields on the edit form. Replace the admin.site.register(Question) line with:

from django.contrib import admin

from .models import Question


class QuestionAdmin(admin.ModelAdmin):
    fields = [‘pub_date‘, ‘question_text‘]

admin.site.register(Question, QuestionAdmin)

You’ll follow this pattern – create a model admin object, then pass it as the second argument to admin.site.register() – any time you need to

change the admin options for an object.