Django Class Based Views

Django Class-Based Views (CBVs) are Python classes that handle web requests and return web responses. They provide a more organized and reusable way to define logic for a specific URL.

Features of CBVs:

• Separation of Logic: Each HTTP method (like GET or POST) is handled in its own method, keeping the code organized.
• Reusable Components: Common functionality can be written once in base classes or mixins and reused in multiple views using object-oriented techniques like multiple inheritance.
• Built-in Generic Views: Django provides ready-made CBVs like CreateView, ListView, and DetailView for common tasks, saving time and effort.

Using Class based view in Django

Let's Create a Class-based view list view to display instances of a model and a model of which we will be creating instances through our view.

In geeks/models.py:

from django.views.generic.list import ListView
from .models import GeeksModel

class GeeksList(ListView):

    # specify the model for list view
    model = GeeksModel

Now, create a URL path to map the view. In geeks/urls.py:

from django.urls import path

# importing views from views..py
from .views import GeeksList
urlpatterns = [
    path('', GeeksList.as_view()),
]

Create a template in templates/geeks/geeksmodel_list.html:

<ul>
    <!-- Iterate over object_list -->
    {% for object in object_list %}
    <!-- Display Objects -->
    <li>{{ object.title }}</li>
    <li>{{ object.description }}</li>

    <hr/>
    <!-- If objet_list is empty  -->
    {% empty %}
    <li>No objects yet.</li>
    {% endfor %}
</ul>

Visit development server: http://localhost:8000/

Similarly, class based views can be implemented with logics for create, update, retrieve and delete views.

Django Class Based Views - CRUD Operations

Django Class-Based Views (CBVs) make it easier to implement CRUD operations (Create, Read, Update, Delete) by providing built-in generic views. These views save time by handling common patterns with minimal code.

• CreateView: create or add new entries in a table in the database. 
• Retrieve Views: read, retrieve, search, or view existing entries as a list(ListView) or retrieve a particular entry in detail (DetailView) 
• UpdateView: update or edit existing entries in a table in the database 
• DeleteView: delete, deactivate, or remove existing entries in a table in the database 
• FormView: render a form to template and handle data entered by user

These operations power common features like user management, blog posts, and product catalogs, making Class-Based Views a powerful and reusable way to build dynamic web applications