Let say I have a taxonomy name Flavor and the terms have Vanilla, Chocolate and Green Tea.
I also have a content type name ice-cream with flavor field under 'Flavor' taxonomy which can multiple select.
I create a ice-cream page name Baskin Robin and I tick 'Vanilla' and 'Chocolate' under flavor field.
How to list all 'Flavor' terms in node.html.twig and add a class for 'Vanilla' and 'Chocolate'?
For example:
<div class="field-item active">Vanilla</div>
<div class="field-item active">Chocolate</div>
<div class="field-item">Green Tea</div>
You need a block or a views to do that.
You can also use a hook_preprocess_node to inject all flavors in the ice-cream template.
Here the documentation to create a custom block.
Here the documentation to create a views block.
Here the documentation to place a block (custom or views).
I will explain the easiest & fastest, but most dirty one, to achieve your goal - using the hook_preprocess_node.
I recommend to use the custom block or the views for scalability & maintainability. The code below is a working example, you could use it in a custom block.
Here the code using the preprocess way.
In your template.theme file:
/**
* Implements hook_preprocess_node.
*/
function template_preprocess_node(&$variables) {
$node = $variables['node'];
if($node->bundle() == 'ice-cream') {
// Should be injected.
$termStorage = \Drupal::entityManager()->getStorage('taxonomy_term');
// Load all flavors taxonomy term.
$variables['flavors'] = $termStorage->loadTree('flavors', 0, NULL, TRUE);
}
}
In your node.html.twig or node--ice-cream.html.twig:
{% for flavor in flavors %}
{% set classes = ['field-item'] %}
{% for node_flavor in node.field_flavors if node_flavor.target_id == flavor.id %}
{% set classes = classes|merge(['active'])%}
{% endfor %}
<div class="{{ classes|join(' ') }}">{{ flavor.name.value }}</div>
{% endfor %}
Hope it will help you !
Related
How can I make the for product in products loop break after the if condition is fulfilled 3 times. I have been trying to set up a counter but that isn't working... because set is not accepted inside of for loops. Though testing it out a bit more it isn't being accepted anywhere.
When I use set it throws this exception or a variation of it: Invalid block tag on line 11: 'set', expected 'endblock'. Did you forget to register or load this tag?
I am aware that I should put all the logic I'm using Templates for inside of the view and then pass it through the dictionary but it would take too much time to research everything about that and i just want to be done with this.
Honestly I am really tired it is 6am and idk what to do. Thank you for your help in advance. :)
Edit: I know I have to use namespace() for set to be able to propagate across scopes. But set itself is still raising the same exception as above.
Edit2: I thought that django uses jinja2 as it's templating language but it seems like that is not the case. I fixed the mentions of jinja2 as I haven't changed any of the defaults that come with a fresh install of django.
HTML
{% for category in categories %}
<div>
<h5 class="text-line"><span>{{category.name}}</span></h5>
</div>
<!-- Cards Container -->
<div class="shop-cards">
{% set counter = 0 %}
{% for product in products %}
{% if product.category.categoryID == category.categoryID %}
<!-- CARD 1 -->
<div class="card">
<image class="product-image" src="{% static 'images/product-4.png' %}"></image>
<div class="card-category-price">
<h3 class="product-name">{{product.name}}</h3>
<h3 class="product-price">{{product.price}}</h3>
</div>
</div>
{% endif %}
{% endfor %}
</div>
{% endfor %}
You can't (by design).Django is opinionated by design, and the template language is intended for display and not for logic.
You can use Jinja instead.
Or, you can do the complicated stuff in Python and feed the results to the template language through the context. Bear in mind that appending arbitrary objects to a list in Python is a cheap operation. So (in a CBV) something like
context['first_three'] = self.get_first_three( whatever)
...
def get_first_three(self, whatever):
first_three = []
for obj in ...:
if complicated stuff ...
first_three.append( obj)
if len(first_three) == 3:
break
return first_three
BTW you can't (easily?) implement break in Django templating, but you can easily give it the ability to count:
class Counter( object):
def __init__(self):
self.n = 0
def value(self):
return self.n
def incr(self):
self.n += 1
return ''
In the context pass context['counter'] = Counter()
In the template refer to {{counter.value}} as much as you want, and in a conditional where you want to count occurences, use {{counter.incr}}. But, it's hacky, and probably best avoided.
The problem seems to arise due to a misconception of the templating functionality. It is to be used mainly for display purposes and not filtering purposes, and you are facing a filtering problem:
I want to filter the 3 first elements of a list that fulfill a specific condition
is your main issue and templating frameworks will be poor at solving your issue, whereas this is exactly what python and Django's ORM are good at.
Why don't you first filter in Django, then display in template? For example as follows:
...
products = queryset.filter(abc=condition)[:3]
context = Context({ 'products': products })
return HttpResponse(template.render(context))
This seems to me like a very simple question, but I can't seem to find the answer.
All I need to do is determine the number of objects returned by a database query.
The specific circumstance is this: I have a model named Student. This model has a ManyToManyField member named courses_current, which relates to a table of Course models. When I pass my Student instance to a template, I want to be able to do something like the following (the syntax may not be exact, but you'll get the basic idea):
<div id="classes">
{% if student.classes_current.all.size == 0 %}
<h1> HEY! YOU AREN'T TAKING ANY CLASSES! REGISTER NOW!
{% else %}
Here are your courses:
<!-- ... -->
{% endif %}
</div>
Now, I'm fairly certain that X_set.all.size is not a real thing. In the manage.py shell I can just use len(student.classes_current.all()), but I don't know of any way to use built-in functions, and "dictionary-like objects" don't have .size() functions, so I'm at a loss. I'm sure there's a very simple solution (or at least I hope there is), but I can't seem to find it.
{{ student.classes_current.all.count }} but be warned that it doesn't fetch the objects so you will need to do a separate query if you want to loop over them.
If you need loop over the classes for tag has way to get what you need.
{% for cl in student.current_classes.all %}
{{ cl }}
{% empty %}
<h1>Hey! ...</h1>
{% endfor %}
Documentation https://docs.djangoproject.com/en/dev/ref/templates/builtins/?from=olddocs#for-empty
I need a javascript templating system and i think handlebars.js does an excellent job in this case.
I'm having syntax conflicts with handlebars templates inside a django template because django tries to render handlebars variables.
Is there a tag in django templates to stop rendering a block with curly braces?
Something like:
{{ django_context_varable }} #works
{{% raw %}}
<script id="restaurants-tpl" type="text/x-handlebars-template">
<ul>
{{#restaurants}} #not rendered by django, plain text
<li>{{name}}</li>
{{/restaurants}}
</ul>
</script>
{{% endraw %}}
Edit
Likely i found this. It works fine.
Update
Django 1.5 supports verbatim tag natively.
I use a custom template tag for another js templating system, here:
https://gist.github.com/629508
Use in template:
{% load mytags %}
{% verbatim %}
{{ This won't be touched by {% django's %} template system }}
{% endverbatim %}
Edit: This custom template tag is no longer necessary, as Django's template language now supports the {% verbatim %} template tag.
Is there a tag in django templates to stop rendering a block with curly braces?
OLD Answer for Django 1.0-1.4: No, though you could though you could put the block in a separate file and include it without rendering or use a different templating engine.
New Answer: The answer above was correct in August 2011 when the question was asked and answered. Starting in Django 1.5 (released Feb 2013, though alpha/beta versions in late 2012), they introduced the {% verbatim %} and {% endverbatim %} which will prevent the django template engine from processing the content in the block.
So for the question asked the following will work in django 1.5+ out of the box:
{{ django_context_varable }} #works
{% verbatim %}
<script id="restaurants-tpl" type="text/x-handlebars-template">
<ul>
{{#restaurants}} #not rendered by django, plain text
<li>{{name}}</li>
{{/restaurants}}
</ul>
</script>
{% endverbatim %}
The documentation on verbatim is here. Yes, this was noted by others earlier, but as this is the accepted answer I should list the easiest solution.
I wrote a very small django application : django-templatetag-handlebars exactly for that purpose.
{% load templatetag_handlebars %}
{% tplhandlebars "tpl-infos" %}
{{total}} {% trans "result(s)." %}
<p>{% trans "Min" %}: {{min}}</p>
<p>{% trans "Max" %}: {{max}}</p>
{% endtplhandlebars %}
Render your block as usual using Handlebars.js API :
var properties = {
total: 10,
min: 5,
max: 4
};
var template = Handlebars.compile($('#tpl-infos').html()),
rendered = template(properties);
I wrote it the day #chrisv published its package, with a KISS approach in mind. It is mainly based on Miguel Araujo's gist : https://gist.github.com/893408.
for a deeper integration between handlebars and Django (including optional on-the-fly precompilation) check out my project at
https://bitbucket.org/chrisv/django-handlebars/
It basically works like this:
create HB template under
appdirectory/hbtemplates/myapp/template.html
(just like Django template)
in your app, use
{% handlebars myapp %}
template tag and render template like so:
Handlebars.templates["myapp.template.html"]({context:"value"});
Compile your handlebars first!
From handlebars precompiling documentation:
In addition to reducing the download size, eliminating client-side compilation will significantly speed up boot time, as compilation is the most expensive part of Handlebars.
You can compile templates in your build environment using handlebars npm module, or integrate it with a build tool like gulp with gulp-handlebars.
After compiling, your handlebars templates can be served as static resources and bypass server side rendering altogether. Makes it easier on caching too :)
Typical usage would look like this:
<div id="restaurants-tpl">
Waiting for content...
</div>
<script src="{% static 'js/handlebars.runtime.js' %}"></script>
<script src="{% static 'js/templates.js' %}"></script>
<script>
// Let django render this as a json string
properties = {{ properties }};
// Use Handlebars compiled template imported above
rendered_html = Handlebars.templates["restaurants-tpl"](properties);
// Set element content
document.getElementById("restaurants-tpl").innerHTLM = rendered_html;
</script>
Django's templating system doesn't support escaping blocks at a time. It would be easy to work around were it not for the fact that when templates are processed the tokenizer doesn't keep exact information on what the tokens looked like before they got tokenized.
I have used the following work-around which is ugly, but (sort of) works. Use different tag delimiters in your templates and a django template tag that translates those back to what you actually want:
#register.tag(name="jstemplate")
def do_jstemplate(parser, token):
while self.tokens:
token = self.next_token()
if token.token_type == TOKEN_BLOCK and token.contents == endtag:
return
self.unclosed_block_tag([endtag])
nodelist = parser.parse( ('endjstemplate',) )
parser.delete_first_token()
s = token.split_contents()
tmpl_id = Variable( s[1] ) if (len(s) == 2 and s[1]) else ''
return JsTemplateNode( nodelist, tmpl_id )
class JsTemplateNode(template.Node):
def __init__(self, nodelist, tmpl_id=''):
self.tmpl_id = tmpl_id
self.nodelist = nodelist
def render(self, context):
content = self.nodelist.render(context)
return u'<script id="%s" type="text/x-handlebars-template">%s</script>' % (
self.tmpl_id.resolve(context),
re.sub( ur'{\$(.*?)\$}', u'{{\\1}}', content ), )
For bonus points you can leverage Django's templates within your templates ...
which will probably cook your brain trying to untangle later:
{% jstemplate "restaurants-tpl" %}
{$#restaurants$}
<div id="<$name$<" class="{$type$}">
<ul class="info">
{$#if info/price_range$}<li><em>{{ trans "Price Range" }}:</em> {$info/price_range$}</li>{$/if$}
{$#if info/awards$}<li><em>{{ trans "Awards" }}:</em> {$info/awards$}{$/if$}
</ul>
<div class="options">
<button>{% trans "Reservation" %}</button>
</div>
</div>
{$/restaurants$}
{% jstemplate %}
Actually I wrote a custom template filter which goes like this:
from django import template
register = template.Library()
def handlebars(value):
return '{{%s}}' % value
register.filter('handlebars', handlebars)
and use it in a template like so:
{{"this.is.a.handlebars.variable"|handlebars}}
It's the simplest thing I could think of. You just have to put your handlebars variable name in quotes. I regret I hadn't got this idea before I struggled with ssi. It works also with keywords:
{{"#each items"|handlebars}}
Why not use jinja2 instead? IMO, they're both elegant to use. Here's an excellent article about it: Using Jinja2 with Django
I'm looking how to do the best something like a UserControl in ASP.NET in Django.
For example:
1) There's a Book model defined
2) There's a regular representation of the book which I want to use all over my site (called "book_template.html").
Now let's say I want to use this one representation from 2 views: recent_books_view, popular_books_view. It can be done directly like
from django import template
t = template.Template('My name is {{ name }}.')
book1_context = template.Context({'book': Book1})
book2_context = template.Context({'book': Book2})
book3_context = template.Context({'book': Book3})
...
render_to_response('recent_books.html',
{'content': t.render(book1_context) + t.render(book2_context) + t.render(book3_context)})
render_to_response('popular_books.html',
{'content': t.render(book4_context) + t.render(book5_context) + t.render(book6_context)})
But I'm sure there's a better way...
For example, in ASP.NET you can say in template file "apply for array 'Books' this shared template", and then in the backend you just specify variable 'Books'. Is that possible in Django?
In your python code:
context['books'] = blah blah # Make a list of books somehow.
return render_to_response('popular_books.html', context)
In popular_books.html:
<p>Look, books:</p>
{% for book in books %}
{% include "book.html" %}
{% endfor %}
Finally, in book.html:
<p>I am a book, my name is {{book.name}}</p>
There are more interesting ways to modularize, such as creating a custom tag, so that you could, for example:
<p>Look, books:</p>
{% for b in books %}
{% book b %}
{% endfor %}
I think you're looking for this tutorial Chapter 4 of the Django book: The Django Template System.
See block tags and template inheritance.
I have a base.html template that contains a list of links.
Example:
<div id="sidebar1">
<ul>
<li>Index</li>
<li>Stuff</li>
<li>About Me</li>
<li>Contact Me</li>
</div>
Then I have in my views.py a definition for each of index.html, stuff.html, about.html and contact.html. Each of those templates simply derive from a base.html template and set their own respective titles and contents.
My question is about the above /stuff I have a class="current".
I'd like to make the current page that I'm on have that class attribute.
I could set a different variable in each view like current_page="about" and then do a compare in the template with {% ifequal %} in each class element of each link , but that seems like duplicating work (because of the extra view variable).
Is there a better way? Maybe if there is a way to get the view function name that the template was filled from automatically I would not need to set the extra variable? Also it does seem like a lot of ifequals.
Here's an elegant way to do this, which I copied from somewhere and I only wish I could remember where, so I could give them the credit. 8-)
I assign an id to each of my pages (or all the pages within a section) like this:
In index.html: <body id='section-intro'>...
In faq.html: <body id='section-faq'>...
In download.html: <body id='section-download'>...
And then an id for the corresponding links:
<li id='nav-intro'>Introduction</li>
<li id='nav-faq'>FAQ</li>
<li id='nav-download'>Download</li>
And the in the CSS I set a rule like this:
#section-intro #nav-intro,
#section-faq #nav-faq,
#section-download #nav-download {
font-weight: bold;
/* And whatever other styles the current link should have. */
}
So this works in a mostly declarative way to control the style of the link that the current page belongs in. You can see it in action here: http://entrian.com/source-search/
It's a very clean and simple system once you've set it up, because:
You don't need to mess about with template markup in your links
You don't end up using big ugly switch statements or if / else / else statements
Adding pages to a section Just Works [TM]
Changing the way things look only ever means changing the CSS, not the markup.
I'm not using Django, but this system works anywhere. In your case, where you "set their own respective titles and contents" you also need to set the body id, and there's no other Django markup required.
This idea extends easily to other situations as well, eg. "I want a download link in the sidebar on every page except the download pages themselves." You can do that in CSS like this:
#section-download #sidebar #download-link {
display: none;
}
rather than having to put conditional template markup in the sidebar HTML.
Haven't used Django, but I've dealt with the same issue in Kohana (PHP) and Rails.
What I do in Kohana:
<li><a href="/admin/dashboard" <?= (get_class($this) == 'Dashboard_Controller') ? "class=\"active\"" : NULL ?>>Dashboard</a></li>
<li><a href="/admin/campaigns" <?= (get_class($this) == 'Campaigns_Controller') ? "class=\"active\"" : NULL ?>>Campaigns</a></li>
<li><a href="/admin/lists" <?= (get_class($this) == 'Lists_Controller') ? "class=\"active\"" : NULL ?>>Lists</a></li>
What I do in Rails:
<li><a href="/main" <%= 'class="active"' if (controller.controller_name == 'main') %>>Overview</a></li>
<li><a href="/notifications" <%= 'class="active"' if (controller.controller_name == 'notifications') %>>Notifications</a></li>
<li><a href="/reports" <%= 'class="active"' if (controller.controller_name == 'reports') %>>Reports</a></li>
I see only a couple of ways of doing it, while avoiding repeated ifequals:
Javascript. Something along the lines of (jQuery):
var parts = window.location.pathname.split('/');
var page = parts[parts.length-1];
$('#sidebar1 a[href*=' + page + ']').addClass('current');
Change your views to contain a list of pages with their associated titles and URLs and create a {% for %} loop in your template, which will go through that list, and add a single {% ifequal %}.
Option 2 being the favorite from where I stand. If the logic for all of your pages is the same, and only the templates differ, you might consider using the FlatPages model for each of your pages. If the logic is different, and you need different models, you might consider using a menuing app of some sort. A shameless plug: I have a menuing app of my own
If you add the request context processor, it's pretty straightforward:
settings.py:
TEMPLATE_CONTEXT_PROCESSORS = (
'django.core.context_processors.request',
'django.contrib.auth.context_processors.auth' # admin app wants this too
)
Now you have access to the HttpRequest, which contains the request path. Highlighting the current page is a simple matter of checking if the path matches the link's destination, i.e., you're already there:
<li><a class="{% if request.path == '/' %}current{% endif %}" href="/">Index</a></li>
<li><a class="{% if request.path == '/stuff/' %}current{% endif %}" href="/stuff/">Stuff</a></li>
<li><a class="{% if request.path == '/about/' %}current{% endif %}" href="/about/">About Me</a></li>
<li><a class="{% if request.path == '/contact/' %}current{% endif %}" href="/contact/">Contact Me</a></li>