The reason I ask is that I'm parsing a large List into a Django template, we're talking about 100,000 items being rendered into a table and it's painfully slow at loading!
or is there a method that I've completely missed?
I'm currently using {% regroup %} to group headers together.
with the Paginator class
from django.views.generic import ListView
from myapp.models import Contact
class ContactList(ListView):
paginate_by = 2
model = Contact
and the template
{% for contact in page_obj %}
{# Each "contact" is a Contact model object. #}
{{ contact.full_name|upper }}<br>
...
{% endfor %}
<div class="pagination">
<span class="step-links">
{% if page_obj.has_previous %}
« first
previous
{% endif %}
<span class="current">
Page {{ page_obj.number }} of {{ page_obj.paginator.num_pages }}.
</span>
{% if page_obj.has_next %}
next
last »
{% endif %}
</span>
</div>
https://docs.djangoproject.com/en/3.1/topics/pagination/
Related
book_list.html
{% extends "base.html" %}
{% block content %}
<h3> Available books </h3>
{% if book_list %}
<ul>
{% for book in book_list %}
<li> {{book.title }} <small> by {{book.author }}</small></li>
<p>{{ book.summary }}
{% endfor %}
<ul>
{% endif %}
{% if is_paginated %}
<div class="pagination">
<span class="page-links">
{% if page_obj.has_previous %}
previous
{% endif %}
<span class="page-current">
Page {{ page_obj.number }} of {{ page_obj.paginator.num_pages }}.
</span>
{% if page_obj.has_next %}
next
{% endif %}
</span>
</div>
{% else %}
<h4> pagination not working</h4>
{% endif %}
{% endblock %}
class in views.py :
class BookListView(generic.ListView):
model = Book
paginate_by = 2
queryset =Book.objects.all()
urls.py :
urlpatterns =[
url('^$',views.index, name ='index'), # matching with an empty string
url('^books/$',views.BookListView.as_view(),name ='books'), #the one to which I am adding the paginator
url('^book/(?P<pk>\d+)/$',views.BookDetailView.as_view(),name='book-detail'),
]
Book model :
class Book(models.Model):
title=models.CharField(max_length=100)
author = models.ForeignKey('Author',on_delete=models.SET_NULL,null = True)
summary = models.TextField(max_length=200,help_text="Enter the description")
isbn = models.CharField('ISBN',max_length=13 ,help_text='13 Character ISBN number' )
genre = models.ManyToManyField(Genre,help_text = 'selct a genre for this book')
class Meta:
ordering =["title"]
def __str__(self):
return self.title
def get_absolute_url(self):
return reverse('book-detail',args=[str(self.id)] )
The book_list gets rendered perfectly, the problem is with the paginator, the is_paginated condition is not working and it executes the else statement, I have been trying for more than 3 hours, but couldn't find a solution, What Am I missing here ?
Django version : 1.11.2
Python : 3.5
Edit :
update 1: The problem was the paginate_by value was two, and the total items to display was also two hence it didn't initiate the is_paginated tag,It worked fine when I added one item more than paginate_by value.
use this, you had some problem with the if condition
{% extends "base.html" %}
{% block content %}
<h3> Available books </h3>
{% if object_list %}
<ul>
{% for book in object_list %}
<li> {{book.title }} <small> by {{book.author }}</small></li>
<p>{{ book.summary }}
{% endfor %}
<ul>
{% if is_paginated %}
<div class="pagination">
<span class="page-links">
{% if page_obj.has_previous %}
previous
{% endif %}
<span class="page-current">
Page {{ page_obj.number }} of {{ page_obj.paginator.num_pages }}.
</span>
{% if page_obj.has_next %}
next
{% endif %}
</span>
</div>
{% else %}
<h4> pagination not working</h4>
{% endif %}
{% else %}
<h4> No book</h4>
{% endif %}
{% endblock %}
I'm building a simple blog app using Django.
This app has a main template blog.html which is shared between the following views:
blog (url: /blog/[page number])
Main page of the blog, displays the last articles
search (url: /search/<query>/[page number])
Will display the articles who match the query
category (url: /category/<category name>/[page number])
Will display the articles from the given category
Each a this views provides the template blog.html with an object page obtained using the function Paginator each time with a different objects list (depending on the view).
Here is my problem:
The template blog.html contains a pager
<ul class="pager">
{% if page.has_previous %}
<li class="previous">
<a href="{{ url_previous_page }}" class="btn btn-primary" >← Older</a>
</li>
{% endif %}
{% if page.has_next %}
<li class="next">
<a href="{{ url_next_page }}" class="btn btn-primary" >Newer →</a>
</li>
{% endif %}
</ul>
How can I define in an elegant way the values of url_next_page and url_previous_page in all the views?
You shouldn't really need to supply the links for the next and previous buttons like that. I would suggest changing your pagination code to be something like this:
<div class="pagination-wrap">
<span class="pagination-links">
{% if page_obj.has_previous %}
{% endif %}
<span class="current">
{{ page_obj.number }} of {{ page_obj.paginator.num_pages }}
</span>
{% if page_obj.has_next %}
{% endif %}
</span>
<div>{{ page_obj.start_index }} to {{ page_obj.end_index }} of {{ page_obj.paginator.count }}</div>
</div>
In your views, all you need to specify is the number of objects to paginate by with paginate_by = 15.
If you really want to, you could create a mixin for your list views to use which has a method that could return the url you want.
I cannot get the contents of an inclusion_tag to display. I am not getting an errors so i know that the tag is registering and I am almost certain that it is loading correctly. The tag is created in crudapp/templatetags/crudapp_tags.py
from django import template
register = template.Library()
#register.inclusion_tag("forum.html")
def results(poll):
form = 'blah'
return {'form': form}
templates/forum.html
{% extends 'index.html' %}
{% load crudapp_tags %}
{% results poll %}
<p>aaa</p>
{% block homepage %}
<p>bbb</p> <!-- Only this displays -->
{% if form %}
<p>Form exists</p>
{% endif %}
{% for item in form %}
<p>This is {{ item }}</p>
{% endfor %}
<div>
<p>{% if user.is_authenticated %}Add a New Topic: <span class="glyphicon glyphicon-plus"></span>{% endif %}</p>
</div>
<div>
<p>{{ totalposts.count }} posts, {{ totaltopics.count }} topics, {{ totalusers.count }} users, {{ totalviews.numviews}} views</p>
</div>
{% endblock %}
The file set up is as follows,
If you are using an inclusion tag, then the tag renders another template. You need to move the code that uses form out of forum.html and into a new template, e.g. results.html
results.html
{% if form %}
<p>Form exists</p>
{% endif %}
{% for item in form %}
<p>This is {{ item }}</p>
{% endfor %}
Then change your tag to use this template
#register.inclusion_tag("results.html")
def results(poll):
form = 'blah'
return {'form': form}
Finally, since you are extending a template, you need to move then tag into a block, otherwise the result won't be used.
{% block homepage %}
{% results poll %}
...
{% endblock %}
If you want to add an item to the template context instead of rendering another template, then you want a simple tag instead.
#register.simple_tag
def fetch_result():
result = ['foo', 'bar']
return result
Then in your template:
{% fetch_result as result %}
{% for item in result %}
<p>This is {{ item }}</p>
{% endfor %}
The {% fetch_result as result %} works for simple tags in Django 1.9+. In earlier versions, you want an assignment tag.
So I'm attempting to implement the pagination for a website that i'm working on, but it seems not to work completely.
class ExampleListView(FormMixin, ListView):
model = Example
template_name = "example.html"
paginate_by = 3
context_object_name = "example_list"
allow_empty = True
page_kwarg = 'page'
paginate_orphans = 0
form_class = ExampleForm
Then in the html I have the following
<tbody>
{% for formset_form in formset %}
...
{% endfor %}
...
{% if is_paginated %}
<div class="pagination">
<span class="page-links">
{% if page_obj.has_previous %}
Previous
{% endif %}
<span class="page-current">
Page {{ page_obj.number }} of {{ page_obj.paginator.num_pages }}
</span>
{% if page_obj.has_next %}
Next
{% endif %}
</span>
</div>
{% else %}
<p></p>
{% endif %}
I currently have 5 forms there in the table, and paginated it by 3. What it does is that is displays Page 1 of 2 Next, like it should, but it displays all of the forms on the pages.
The Django ListView is meant to render 'A page representing a list of objects.'. You try to display a paginated list of formsets. Interesting thought, but not what ListView does.
This answer to a previous question may help you to achieve what you want.
I am using Flask, mongoengine for a project and I am trying to get basic stuff working from http://docs.mongodb.org/manual/tutorial/write-a-tumblelog-application-with-flask-mongoengine/
After implementing everything from above link I added a new field for "tags" in Post and when I try to create a post, my tags doesn't show a input box.
Any help is appreciated.
My code and screenshot below
class Post(db.DynamicDocument):
created_at = db.DateTimeField(default=datetime.datetime.now, required=True)
title = db.StringField(max_length=255, required=True)
slug = db.StringField(max_length=255, required=True)
comments = db.ListField(db.EmbeddedDocumentField('Comment'))
tags = db.ListField(db.StringField(max_length=30)) # New field I added
template form
{% macro render(form) -%}
<fieldset>
{% for field in form %}
{% if field.type in ['CSRFTokenField', 'HiddenField'] %}
{{ field() }}
{% else %}
<div class="clearfix {% if field.errors %}error{% endif %}">
{{ field.label }}
<div class="input">
{% if field.name == "body" %}
{{ field(rows=10, cols=40) }}
{% else %}
{{ field() }}
{% endif %}
{% if field.errors or field.help_text %}
<span class="help-inline">
{% if field.errors %}
{{ field.errors|join(' ') }}
{% else %}
{{ field.help_text }}
{% endif %}
</span>
{% endif %}
</div>
</div>
{% endif %}
{% endfor %}
</fieldset>
{% endmacro %}
rendering form code
{% extends "admin/base.html" %}
{% import "_forms.html" as forms %}
{% block content %}
<h2>
{% if create %}
Add new Post
{% else %}
Edit Post
{% endif %}
</h2>
<form action="?{{ request.query_string }}" method="post">
{{ forms.render(form) }}
<div class="actions">
<input type="submit" class="btn primary" value="save">
Cancel
</div>
</form>
{% endblock %}
From what I can gather, your problem is you're telling WTF to render the tags field, but WTForms doesn't know how to handle that information.
From looking at the Flask-MongoEngine documentation, it seems the ListField is just a FieldList as WTForms refers to it.
Currently you're not actually defining the form independently in WTForms, you're just using the magic included in Flask-MongoEngine, so my first attempt would be to add some more logic to your macro, add a {% elif field.type == 'ListField' %} and try and discover what's contained in there to iterate through to produce your form. From having a quick look at the source-code, something like the following might work.
{% elif field.type == 'ListField %}
{# render_the_group_label #}
{% for subfield in field.entries %}
{% if subfield.type == 'StringField' %}
{# render_the_subfield #}
{% endif %}
{% endfor %}
...
That code will need to be worked on, but hopefully it'll point you in the right direction. Otherwise, I'd actually define the form seperately in WTForms to give you a bit more control on the code-side. Luckily they provide a csv tag example which should help you if you need to go that route. I wrote a guide that takes a different route using #property decorators to achieve a similar effect, which again, might at least point you towards the finish line.