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Pagination in Django ListView when using get_context_data

I am currently facing this problem with Django ListView. Basically, I need to filter some questions per topic and I would like to paginate the results.
My code is working perfectly about the queryset part (the results are showed correctly) but I am facing a problem with pagination.
Let's say I have so far 8 items in my query, if I choose to paginate_by = 10, it shows me just one page. If, otherwise, I choose to paginate by, let's say, 3, it shows me 3 pages to choose in the template (which is correct) but it shows me ALL the results of the query in my page.
I post some code to be more clear
models.py:
class Tag(models.Model):
name = models.CharField(max_length=300, unique=True)
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(auto_now=True)
def clean(self):
self.name = self.name.capitalize()
def __str__(self):
return self.name
class Question(models.Model):
post_owner = models.ForeignKey(User, on_delete=models.CASCADE)
title = models.CharField(max_length=5000, default='')
body = tinymce_models.HTMLField()
tags = models.ManyToManyField(
Tag, related_name='tags')
viewers = models.ManyToManyField(
User, related_name='viewed_posts', blank=True)
views.py:
class TagQuestionsListView(ListView):
template_name = 'main/tag_questions.html'
paginate_by = 20
def get_queryset(self, **kwargs):
tag = Tag.objects.get(name=self.kwargs['name'])
questions = Question.objects.filter(tags=tag)
return questions
def get_contextdata(self, **kwargs):
context = super().get_context_data(**kwargs)
context['tag'] = Tag.objects.get(name=self.kwargs['name'])
context['questions'] = Question.objects.filter(
tags=context['tag'], is_deleted=False)
return context
template:
{% extends 'base.html' %}
{% load humanize %}
{% block title %}Domande su {{tag.name}}{% endblock title %}
{% block content %}
<style>
.text {
overflow: hidden;
text-overflow: ellipsis;
display: -webkit-box;
-webkit-line-clamp: 2; /* number of lines to show */
line-clamp: 2;
-webkit-box-orient: vertical;
}
</style>
<div class="card">
<div class="mt-3">
<h3 class="ms-2" style="display: inline;">Ultime {{ questions.count }} Domande</h3>
{% if request.user.is_authenticated %}
Fai una domanda
{% else %}
Fai una domanda
{% endif %}
</div>
<h5 class="ms-2">{{ total_questions.count }} domande totali </h5>
<hr>
{% for question in questions %}
<div class="row">
<div class="col-2 ms-2">
<p>{{ question.count_all_the_votes }} Voti</p>
<p>{{ question.count_answers }} Risposte</p>
<p>{{ question.calculate_viewers }} Visualizzazioni</p>
</div>
<div class="col-9">
<h5>{{question.title}}</h5>
<div class="text">
{{ question.body|striptags }}
</div>
{% for tag in question.tags.all %}
<a class="btn btn-sm btn-outline-primary m-1" href="{% url 'main:tag_questions' name=tag.name %}">{{tag.name}}</a>
{% endfor %}
<div class="float-end">
<a style="display: inline;" href="">{{question.post_owner}}</a>
{% if question.is_edited == False %}
<span style="display:inline;">creata {{question.created_at | naturaltime}}</span>
{% else %}
<span style="display:inline;"> modificata {{question.edited_time | naturaltime}} da <a style="display: inline;" href="">{{question.edited_by.username}}</a></span>
{% endif %}
</div>
</div>
</div>
<hr>
{% endfor %}
</div>
<div class="row mt-3">
<div class="col-lg-12">
<div class="card">
<div class="card-body">
<nav aria-label="Page navigation example">
<ul class="pagination">
{% if page_obj.has_previous %}
<li class="page-item"><a class="page-link" href="{% url 'main:tag_questions' name=tag.name %}?filter={{ filter }}&orderby={{ orderby }}&page={{ page_obj.previous_page_number }}">Precedente</a></li>
{% else %}
<li class="page-item disabled"><a class="page-link" href="#">Precedente</a></li>
{% endif %}
{% for i in paginator.page_range %}
<li class="page-item {% if page_obj.number == i%} active {% endif %} %} "><a class="page-link" href="?filter={{ filter }}&orderby={{ orderby }}&page={{ i }}">{{i}}</a></li>
{% endfor %}
{% if page_obj.has_next %}
<li class="page-item"><a class="page-link" href="{% url 'main:tag_questions' name=tag.name %}?filter={{ filter }}&orderby={{ orderby }}&page={{ page_obj.next_page_number }}">Prossima</a></li>
{% else %}
<li class="page-item disabled"><a class="page-link" href="#">Prossima</a></li>
{% endif %}
</ul>
</nav>
</div>
</div>
</div>
{% endblock content %}

With this I want my comment converter to answer.
You have to use page_obj instead questions in your template.
<--! ⬇️⬇️⬇️ -->
{% for question in page_obj %}
<div class="row">
<div class="col-2 ms-2">
<p>{{ question.count_all_the_votes }} Voti</p>
<p>{{ question.count_answers }} Risposte</p>
<p>{{ question.calculate_viewers }} Visualizzazioni</p>
</div>
<div class="col-9">
<h5>{{question.title}}</h5>
<div class="text">
{{ question.body|striptags }}
</div>
{% for tag in question.tags.all %}
<a class="btn btn-sm btn-outline-primary m-1" href="{% url 'main:tag_questions' name=tag.name %}">{{tag.name}}</a>
{% endfor %}
<div class="float-end">
<a style="display: inline;" href="">{{question.post_owner}}</a>
{% if question.is_edited == False %}
<span style="display:inline;">creata {{question.created_at | naturaltime}}</span>
{% else %}
<span style="display:inline;"> modificata {{question.edited_time | naturaltime}} da <a style="display: inline;" href="">{{question.edited_by.username}}</a></span>
{% endif %}
</div>
</div>
</div>
<hr>
{% endfor %}
So, if you define attribute paginate_by , than ListView(django docs) adds a paginator and page_obj to the context. To allow the users to navigate between pages, add links to the next and previous page, in your template.

Django pagination not working. Object list is rendering items but not dividing into pages

I'm currently working on an e-commerce site and I'm trying to create a product list page that spans into another page after 4 items have been displayed. rendering the page doesn't produce any error but all items in the database are displayed on the same page and remains the same even after switching to another page.
Here's my views.py:
from django.shortcuts import render, get_object_or_404
from .models import Category, Item
from django.core.paginator import Paginator
def item_list(request, category_slug=None):
category = None
categories = Category.objects.all()
items = Item.objects.filter(available=True)
if category_slug:
category = get_object_or_404(Category, slug=category_slug)
items = items.filter(category=category)
paginator = Paginator(items, 4)
page_number = request.GET.get('page')
page_obj = paginator.get_page(page_number)
return render(request,
'item/list.html',
{'category': category,
'categories': categories,
'page_obj': page_obj,
'items': items})
my urls.py file:
from django.urls import path
from . import views
app_name = 'shop'
urlpatterns = [
path('', views.item_list, name='item_list'),
path('<slug:category_slug>/', views.item_list, name='item_list'),
path('<int:id>/<slug:slug>/', views.item_detail, name='item_detail'),
]
pagination snippet from the template
<nav class="d-flex justify-content-center wow fadeIn">
<ul class="pagination pg-blue">
<!--Arrow left-->
{% if page_obj.has_previous %}
Previous
{% endif %}
<span class="current">
Page {{ page_obj.number }} of {{ page_obj.paginator.num_pages }}.
</span>
{% if page_obj.has_next %}
Next
{% endif %}
</ul>
</nav>
and the logic that displays the products
<div class="row wow fadeIn">
<!--Grid column-->
{% for item in items %}
<div class="col-lg-3 col-md-6 mb-4">
<!--Card-->
<div class="card" style="width: 16rem; height: 25rem">
<!--Card image-->
<div class="view overlay">
<a href="{{ item.get_absolute_url }}">
{% if item.tags and item.label %}
<div class="imgHolder">
<img src="{{ item.image.url }}" class="img-fluid">
<span class="badge badge-pill {{ item.get_label_display }}-color">{{ item.tags }}</span>
</div>
{% else %}
<img src="{{ item.image.url }}" class="img-fluid">
{% endif %}
</a>
<a href="{{ item.get_absolute_url }}">
<div class="mask rgba-white-slight"></div>
</a>
</div>
<!--Card image-->
<!--Card content-->
<div class="card-body text-center" style="height: 9rem;">
<!--Category & Title-->
<a href="{{ item.category.get_absolute_url }}" class="grey-text">
<h5>{{ item.category.name|truncatechars:20 }}</h5>
</a>
<h5>
<strong style="color:red">
{{ item.name }}
</strong>
</h5>
<h6 class="font-weight-bold">
{% if item.discount_price %}
<strong><del>${{ item.price}}</del></strong>
<strong>${{ item.discount_price }}</strong>
{% else %}
<strong>${{ item.price }}</strong>
{% endif %}
</h6>
</div>
<!--Card content-->
</div>
<!--Card-->
</div>
{% endfor %}
</div>
I'd really like to know what I'm doing wrong and I'm also open to alternative means of solving the same problem. Thanks

You are using all the queryset that you are passing to the paginator. You must iterate over the page_obj.object_list.
page_obj = paginator.get_page(page_number)
page_obj_items = page_obj.object_list

you need to loop throw {% for item in page_obj %}

Problems with get_gueryset method in Django

I have a problem with filtering a queryset that after filtering should be paginated, I am using get_queryset to filter the queryset of objects but on the page nothing is displayed. I have a blog page where I have all the post in a list, and are paginated, on the page I have the most common tags and whenever I click on a tag it redirects the user on the page with posts that have that tag and I want them to be displayed in a list and to be paginated like in the initial page but it's not working.
my view:
class TaggedPostListView(ListView):
model = Post
template_name = 'blog/blog.html'
context_object_name = 'posts'
paginate_by = 2
def get(self, request, *args, **kwargs):
context = self.get_context_data(**kwargs)
tags = Post.tags.most_common()[:8]
context['banner_page_title'] = 'Blog'
context['page_location'] = 'home / blog'
context['tags'] = tags
return render(request, self.template_name, context)
def get_context_data(self, **kwargs):
context = {}
return context
def get_queryset(self):
tag = get_object_or_404(Tag, slug=self.kwargs.get('slug'))
return Post.objects.filter(tags=tag).order_by('-published_date')
model:
class Post(models.Model):
class PostCategory(models.TextChoices):
FAMILY = 'FAMILY', _('Family')
BUSINESS = 'BUSINESS', _('Business')
MWRKETING = 'MARKETING', _('Marketing')
SPENDINGS = 'SPENDINGS', _('Spendings')
author = models.ForeignKey(User, on_delete=models.CASCADE)
title = models.CharField(_('Title'), max_length=200, unique=True)
content = models.TextField(_('Content'))
category = models.CharField(_('Category'), max_length=9, choices=PostCategory.choices, default=PostCategory.BUSINESS)
slug = models.SlugField(_('Slug'), max_length=200, blank=True, null=False, unique=True)
tags = TaggableManager(_('Tags'))
published_date = models.DateTimeField(_('Published Date/Time'), auto_now_add=True)
updated_date = models.DateTimeField(_('Updated Date/Time'), auto_now=True)
def __str__(self):
return self.title
def save(self, *args, **kwargs):
if not self.slug:
self.slug = slugify(self.title)
super().save(*args, **kwargs)
#property
def comments_count(self):
return self.comments.count()
url:
path('tag/<slug:slug>/', TaggedPostListView.as_view(), name='tag'),
{% extends 'home/base.html' %}
{% load static %}
{% block content %}
<!--================Blog Area =================-->
<section class="blog_area section-margin">
<div class="container">
<div class="row">
<div class="col-lg-8 mb-5 mb-lg-0">
<div class="blog_left_sidebar">
{% for post in posts %}
<article class="blog_item">
<div class="blog_item_img">
<img class="card-img rounded-0" src="{% static 'img/blog/m-blog-1.jpg' %}" alt="Post Image">
<a href="{% url 'post' post.slug %}" class="blog_item_date">
<h3>{{ post.published_date|date:"d" }}</h3>
<p>{{ post.published_date|date:"M" }}</p>
</a>
</div>
<div class="blog_details">
<a class="d-inline-block" href="{% url 'post' post.slug %}">
<h2>{{ post.title }}</h2>
</a>
<p>{{ post.content|truncatechars:200 }}</p>
<ul class="blog-info-link">
<li><i class="ti-user"></i></li>
{% if post.comments_count %}
<li><i class="ti-comments"></i>{{ post.comments_count }} - Comments</li>
{% else %}
<li><i class="ti-comments"></i>0 Comments</li>
{% endif %}
</ul>
</div>
</article>
{% endfor %}
{% if is_paginated %}
<nav class="blog-pagination justify-content-center d-flex">
<ul class="pagination">
{% if page_obj.has_previous %}
<li class="page-item">
<a href="?page={{ page_obj.previous_page_number }}" class="page-link" aria-label="Previous">
<span aria-hidden="true">
<span class="ti-arrow-left"></span>
</span>
</a>
</li>
{% endif %}
{% for num in page_obj.paginator.page_range %}
{% if page_obj.number == num %}
<li class="page-item active">
{{ num }}
</li>
{% elif num > page_obj.number|add:'-3' and num < page_obj.number|add:'3' %}
<li class="page-item">
{{ num }}
</li>
{% endif %}
{% endfor %}
{% if page_obj.has_next %}
<li class="page-item">
<a href="?page={{ page_obj.next_page_number }}" class="page-link" aria-label="Next">
<span aria-hidden="true">
<span class="ti-arrow-right"></span>
</span>
</a>
</li>
{% endif %}
</ul>
</nav>
{% endif %}
</div>
</div>
<div class="col-lg-4">
<div class="blog_right_sidebar">
<aside class="single_sidebar_widget search_widget">
<form action="#">
<div class="form-group">
<div class="input-group mb-3">
<input type="text" class="form-control" placeholder="Search Keyword">
<div class="input-group-append">
<button class="btn" type="button"><i class="ti-search"></i></button>
</div>
</div>
</div>
<button class="button rounded-0 w-100" type="submit">Search</button>
</form>
</aside>
<aside class="single_sidebar_widget post_category_widget">
<h4 class="widget_title">Category</h4>
<ul class="list cat-list">
<li>
<a href="#" class="d-flex">
<p>Resaurant food</p>
<p>(37)</p>
</a>
</li>
<li>
<a href="#" class="d-flex">
<p>Travel news</p>
<p>(10)</p>
</a>
</li>
<li>
<a href="#" class="d-flex">
<p>Modern technology</p>
<p>(03)</p>
</a>
</li>
<li>
<a href="#" class="d-flex">
<p>Product</p>
<p>(11)</p>
</a>
</li>
<li>
<a href="#" class="d-flex">
<p>Inspiration</p>
<p>21</p>
</a>
</li>
<li>
<a href="#" class="d-flex">
<p>Health Care (21)</p>
<p>09</p>
</a>
</li>
</ul>
</aside>
<aside class="single_sidebar_widget popular_post_widget">
<h3 class="widget_title">Recent Post</h3>
{% for post in recent_posts %}
<div class="media post_item">
<img src="img/blog/popular-post/post1.jpg" alt="post">
<div class="media-body">
<a href="single-blog.html">
<h3>{{ post.title }}</h3>
</a>
<p>{{ post.date_posted|date:"F m, Y" }}</p>
</div>
</div>
{% endfor %}
</aside>
<aside class="single_sidebar_widget tag_cloud_widget">
<h4 class="widget_title">Post Tags</h4>
<ul class="list">
{% for tag in tags %}
<li>
{{ tag }}
</li>
{% endfor %}
</ul>
</aside>
<aside class="single_sidebar_widget instagram_feeds">
<h4 class="widget_title">Instagram Feeds</h4>
<ul class="instagram_row flex-wrap">
<li>
<a href="#">
<img class="img-fluid" src="img/instagram/widget-i1.png" alt="">
</a>
</li>
<li>
<a href="#">
<img class="img-fluid" src="img/instagram/widget-i2.png" alt="">
</a>
</li>
<li>
<a href="#">
<img class="img-fluid" src="img/instagram/widget-i3.png" alt="">
</a>
</li>
<li>
<a href="#">
<img class="img-fluid" src="img/instagram/widget-i4.png" alt="">
</a>
</li>
<li>
<a href="#">
<img class="img-fluid" src="img/instagram/widget-i5.png" alt="">
</a>
</li>
<li>
<a href="#">
<img class="img-fluid" src="img/instagram/widget-i6.png" alt="">
</a>
</li>
</ul>
</aside>
<aside class="single_sidebar_widget newsletter_widget">
<h4 class="widget_title">Newsletter</h4>
<form action="" method="POST">
{% csrf_token %}
<div class="form-group">
<input type="email" class="form-control" name="newsletter_email" placeholder="Enter email" required>
</div>
<button class="button rounded-0 w-100" type="submit">Subscribe</button>
</form>
</aside>
</div>
</div>
</div>
</div>
</section>
<!--================Blog Area =================-->
{% endblock %}

The problem is not get_queryset, the problem is that get_context_data, the method that is supposed to produce a dictionary that contains the context variables, no longer can work properly because you let it return an empty dictionary. You simply should override it, and add the items you want to pass to the template:
class TaggedPostListView(ListView):
model = Post
template_name = 'blog/blog.html'
context_object_name = 'posts'
paginate_by = 2
def get_context_data(self, **kwargs):
context = super().get_context_data(**kwargs)
tags = Post.tags.most_common()[:8]
context['banner_page_title'] = 'Blog'
context['page_location'] = 'home / blog'
context['tags'] = tags
return context
def get_queryset(self):
tag = get_object_or_404(Tag, slug=self.kwargs.get('slug'))
return Post.objects.filter(tags=tag).order_by('-published_date')
In the template, you need to enumerate over the page_obj if you want to paginate, so:
{% for post in page_obj %}
# …
{% endfor %}

Django paginator issue

I am currently working on a django blog and I've coded a search bar where you type something and, if there's any post that contains what you've typed in the title, it should appear all the posts. This part is perfectly well-written. However, there's an error with the pagination. As you'll see in the views.py. The maximum num of posts per page is 3. However, you can see there's four. However, the paginator detects there should be another page for the fourth posts. Here's an image that shows that.
Here's the views.py:
class ElementSearchView(View):
elements_list = Element.objects.all()
def get(self, request, *args, **kwargs):
paginator = Paginator(self.elements_list, 3)
page_request_var = 'page'
page = request.GET.get(page_request_var)
try:
paginated_queryset = paginator.page(page)
except PageNotAnInteger:
paginated_queryset = paginator.page(1)
except EmptyPage:
paginated_queryset = paginator.page(paginator.num_pages)
queryset = Element.objects.all()
query = request.GET.get('q')
if query:
queryset = queryset.filter(
Q(title__icontains=query)
).distinct()
context = {
'query': queryset,
'queryset': paginated_queryset,
'page_request_var': page_request_var,
}
return render(request, 'periodic/search_results_table.html', context)
And here's the html template: The pagination is at the end of the template.
{% load static %}
<html>
{% include 'periodic/head_search.html' %}
<body>
{% include 'periodic/header.html' %}
<br>
<br>
<div class="container">
<div class="row">
<!-- Latest Posts -->
<main class="posts-listing col-lg-8">
<div class="container">
<div class="row">
<!-- post -->
{% for element in query %}
<div class="post col-xl-6 wrap-login100">
<div class="post-thumbnail"><img src="{{ element.thumbnail.url }}" alt="..." class="img-fluid"></div>
<div class="post-details">
<a href="{{ element.get_absolute_url }}">
<h3 class="h4">{{ element.title }}</h3></a>
</div>
</div>
{% endfor %}
</div>
<!-- Pagination -->
<nav aria-label="Page navigation example">
<ul class="pagination pagination-template d-flex justify-content-center">
{% if queryset.has_previous %}
<li class="page-item"> <i class="fa fa-angle-left"></i></li>
{% endif %}
<li class="page-item">{{ queryset.number }}</li>
{% if queryset.has_next %}
<li class="page-item"> <i class="fa fa-angle-right"></i></li>
{% endif %}
</ul>
</nav>
{% if is_paginated %}
<nav aria-label="Page navigation example">
<ul class="pagination pagination-template d-flex justify-content-center">
{% if page_obj.has_previous %}
<li class="page-item"> <i class="fa fa-angle-left"></i></li>
{% endif %}
<li class="page-item">{{ page_obj.number }}</li>
{% if page_obj.has_next %}
<li class="page-item"> <i class="fa fa-angle-right"></i></li>
{% endif %}
</ul>
</nav>
{% endif %}
</div>
</main>
</body>
{% include 'periodic/scripts_search.html' %}
</html>

As the user #ikilnac mentioned,
you are looping over the original queryset and not the paged one in your template
That simply means that in your loop, you do this
{% for element in query %}
<div class="post col-xl-6 wrap-login100">
<div class="post-thumbnail"><img src="{{ element.thumbnail.url }}" alt="..." class="img-fluid"></div>
<div class="post-details">
<a href="{{ element.get_absolute_url }}">
<h3 class="h4">{{ element.title }}</h3></a>
</div>
</div>
{% endfor %}
And then after that, you are using the tag in the form of {% if queryset.has_previous %} with the original queryset rather than the paged one in the template (the query).
There's a good example of it here - Paginate with Django

Keep getting Server Error - 500

Every time I request a blog post on my website, I receive a server error 500. I have been trying to debug it for the past 3 days, and I have not been able to figure out what is going on. Here is the views.py for the blog detail:
def blog_detail():
post = Post.objects.get(request_post)
try:
Next_Post_id = (post.id + 1)
Next_Post = Post.objects.get(id=Next_Post_id)
Next_Post = Next_Post.id
except ObjectDoesNotExist:
Next_Post = None
# Previous Post
try:
Previous_Post_id = (post.id - 1)
Previous_Post = Post.objects.get(id=Previous_Post_id)
Previous_Post = Previous_Post.id
except ObjectDoesNotExist:
Previous_Post = None
context = {'post': post, 'Next_Post': Next_Post, 'Previous_Post': Previous_Post}
return render(request, "BlogHome/pages/post.html", context)
and here is the post.html template:
{% extends "BlogHome/includes/WELL.html" %}
{% block content %}
<script>
document.title = "Pike Dzurny | {{post.title}}"
</script>
<div class="container-fluid text-center">
<center>
<div class="well" id="WellPost">
<div class="container-fluid">
<h2 align="center" id="TitleText">{{post.title}}</h2>
<h3 align="center" id="BodyText">{{ post.date|date:"m-d"}}</h3>
<h3 align="left">{{ post.body|safe }}</h3>
{% if post.id == 1 %}
<ul class="pager">
<li class="previous disabled"><a href="/blog/{{ Previous_Post.id }}"><span
aria-hidden="true">←</span> Older</a></li>
<li class="next "><a href="/blog/{{ Next_Post.id }}">Newer <span
aria-hidden="true">→</span></a></li>
<h1>hi 1</h1>
</ul>
{% if Next_Post is defined %}
<ul class="pager">
<li class="previous disabled"><span aria-hidden="true">←</span> Older</li>
<li class="next">Newer <span aria-hidden="true">→</span>
</li>
</ul>
<h1>2</h1>
{% Previous_Post is defined %}
<ul class="pager">
<li class="previous"><a href="/blog/{{ Previous_Post.id }}"><span aria-hidden="true">←</span>
Older</a></li>
<li class="next disabled">Newer <span aria-hidden="true">→</span></li>
</ul>
<h1>3</h1>
{% else %}
<ul class="pager">
<li class="previous disabled"><span aria-hidden="true">←</span> Older</li>
<li class="next disabled">Newer <span aria-hidden="true">→</span></li>
</ul>
<h1>4</h1>
{% endif %}
</div>
<div class="container-fluid">
</div>
</center>
</div>
{% endblock %}
Post is the model that contains the blog post. I have not been able to find the reasong why when I request a blog page it throws an error. Does anyone know why?

I figured out what happened. After #Tnerual's comment, I checked my urls.py and realized request_post wasn't defined.