I have a for loop in Django template. After that, I check for coincidences. But in some cases, there are might be 3 coincidences. I need to show only the first coincidence. Now, my code returns the name for 3 times, because, there are 3 coincidences
{% for ip in ips %}
{% if d.name == ip.name %}
<strong>{{ d.name}} </strong>
{% endif %}
{% endfor %}
SOLUTION
It is impossible to break forloop in django template, so I decided to change in views.py through queryset distinction of similar names
ips = Point.objects.defer('point').order_by('name').distinct('name')
I don't recommend doing this in Django Template , but in views itself. But if you can't then you can use {{ forloop|break }}.
Something like this :
{% for ip in ips %}
{% if d.name == ip.name %}
{{ forloop|break }}
<strong>{{ d.name}} </strong>
{% endif %}
{% endfor %}
Check the small snippet example here...
I have few instances of model.
my model:
class Record(models.Model):
name = models.ForeignKey(Car)
image = models.ImageField(upload_to='images/')
created = models.DateTimeField(
default=timezone.now)
view:
def allrecords(request):
records = Record.objects.all().order_by('created')
return render(request, 'mycar/allrecords.html', {'records' : records})
I want show it on my website. In my template i have:
{% for record in records %}
<img src={{ record.image.url}}/>
<div>
{{record.name}}
</div>
{% endfor %}
Now i get list of my records, but i would like put the newest record to first div, next to second etc. How can i do that?
I show simple screen how i would like have that (if someone will create new record, it will go to first div and other records will change place. Is any possibility to do something like that?
edit:
<div>
{% for record in records %}
{% if forloop.counter == 1 %}
<img src={{ record.image.url}}/>
<div>
{{record.name}}
</div>
{% endif %}
{% endfor %}
</div>
<div>
{% for record in records %}
{% if forloop.counter == 2 %}
<img src={{ record.image.url}}/>
<div>
{{record.name}}
</div>
{% endif %}
{% endfor %}
</div>
.
.
# till your 5th image
You can use forloop.counter to get the iteration number and check what is the iteration the loop and handle data accordingly.
In addition you can use CSS to make the layout work as you want.
Here is the information for Django template counter
Edit :
{% for record in records %}
<div>
{% if forloop.counter == 1 %}
# Here you can get your first images
<img src={{ record.image.url}}/>
<div>
{{record.name}}
</div>
{% endif %}
</div>
<div>
{% if forloop.counter == 2 %}
# Here you can get your first images
<img src={{ record.image.url}}/>
<div>
{{record.name}}
</div>
{% endif %}
</div>
.
.
# till your 5th image
{% endfor %}
There are two ways to do this. If you want to set this option for a single view then:
def all_records(request):
records = Record.objects.all().order_by('-created')
return render(request, 'mycar/allrecords.html', {'records' : records})
You're almost correct but order_by('created') leads to asceding order while order_by('-created') leads to descending order which is what you require.
Alternatively, if you want to have this setting to apply to all views then set class Meta in your models.py which will ensure that wherever you use Record.objects.all() it returns Records in descending order of created field:
class Record(models.Model):
name = models.ForeignKey(Car)
image = models.ImageField(upload_to='images/')
created = models.DateTimeField(
default=timezone.now)
class Meta:
ordering = ('-created')
It's Django design pattern to make all logical decisions in models and views and only just plugin formatted data in templates. You shouldn't add any complex logic in templates.
I'm assuming the question means that the model might have more than 5 records. If so, a more generic solution would be
<div class='row'>
<div class='firstimage'>
<img src={{ records[0].image.url}}/>
{{record.name}}
</div>
{% for record in records %}
{% if forloop.counter > 1 %}
<div class='subsequentimage'>
<img src={{ record.image.url}}/>
{{record.name}}
</div>
{% endif %}
{% cycle "" "</div><div class='row'>" "" %}
{% endfor %}
</div>
Note the use of the 'cycle' tag to begin a new row div every third cell div.
I don't know what your CSS classes are to distinguish between rows and cells so I used 'row', 'firstimage' (which might be defined to take up twice as much width) and 'subsequentimage' as example classes.
I recommend you to use the context variables:
def all_records(request):
records = Record.objects.all().order_by('-created')
newest = records[:5]
oldest = records[5:]
return render(request, 'mycar/allrecords.html', {'newst' : newest,
'oldest': oldest })
In your template :
{% for new in newst %}
<div>what you want with news</div>
{% endfor %}
{% for old in oldest %}
<div>what you want with olds</div>
{% endfor %}
In the template I get the whole DropDown correctly shown with something like this:
{{form.deal_type}}
But what if I wanted just the text of the selected dropdown shown?
This shows me just a foreignkey.
{{form.deal_type.value}}
I don't know why you want to do this exactly, but try this.
TO LOOP:
{% for value, text in form.deal_type.field.choices %}
{{ value }}: {{ text }}
{% if value == form.deal_type.value %}
<strong>{{ text }}</strong> <!-- THIS IS THE SELECTED ONE... -->
{% endif %}
{% endfor %}
EDIT:
I meant the above code as an illustration, not that you should use it verbatim. This code will do more like what you want.
{{ form.deal_type.label_tag }}
{% for value, text in form.deal_type.field.choices %}
{% if value == form.deal_type.value %}
{{ text }}
<input type="hidden" name="deal_type" value="{{ value }}" />
{% endif %}
{% endfor %}
I had a similar issue. To solve it I just passed the value to the template directly from the view. So in your view you presumably have something in the way of
data = {'form' :form,}
return render_to_response('destination.html', data, context_instance = RequestContext)
In data you are passing the form that includes deal_type. Add to
data a variable deal_type set equal to Object.deal_type.display_value with
data = {'form' :form,}
if Object.deal_type: data['deal_type'] = Object.deal_type.display_value
return render_to_response('destination.html', data, context_instance = RequestContext)
Then on your template you can just use
{% if condition_to_show_just_text %}
{{deal_type}} {{form.deal_type.as_hidden}}
{% else %}
{{form.deal_type}}
{% endif %}
It may be insiginificant in this case, but it seemed to me that if the list was long, iterating with the for loop on the template would be less efficient than pulling directly from the object
It is able to write {{ myval.add:5 }}, {{ myval|add:value }} and even {{ myval|add:-5 }}.
However, I can't find out what I should type to add value * -1 like {{ myval|add:-value }}. This doesn't work, sadly.
You need to use double quotes:
{{ myval|add:"-5" }}
This subtracts five from myval.
The built-in Django template tags/filters aren't all-encompassing, but it's super easy to write your own custom template tags: https://docs.djangoproject.com/en/dev/howto/custom-template-tags/
You could make your own subtract template tag pretty easily:
#register.filter
def subtract(value, arg):
return value - arg
Use django-mathfilters from PyPI: https://pypi.python.org/pypi/django-mathfilters
To install :
$ pip install django-mathfilters
Then add mathfilters in your INSTALLED_APPS.
In template:
{% load mathfilters %}
<ul>
<li>8 + 3 = {{ 8|add:3 }}</li>
<li>13 - 17 = {{ 13|sub:17 }}</li>
{% with answer=42 %}
<li>42 * 0.5 = {{ answer|mul:0.5 }}</li>
{% endwith %}
{% with numerator=12 denominator=3 %}
<li>12 / 3 = {{ numerator|div:denominator }}</li>
{% endwith %}
<li>|-13| = {{ -13|abs }}</li>
</ul>
I recently started working with Django and stumbled upon this one as well: I needed a very simple template loop that stops printing after n times and shows a "more" link to toggle the rest of the items.
With great interest I read the struggle of people trying to understand why this is not being added to the Django default filters (since before 2013). I didn't feel like creating a custom template tag and I kind of found a way to subtract 2 variables using strings and add in combination with with and stringformat
Let's say I have a list of items where I want to print the first 2 and hide the rest, showing how many hidden items are there, eg.
John, Anna and 5 others like this (when given a list of 7 items)
As long as the number of visible items is harcoded in the template (eg. 2), it's possible to add the negative 2 |add:"-2", but I wanted the number of visible items to be a variable as well. The Math-filter library as suggested above doesn't seem up to date (I haven't tested it with Django 2.x).
The trick seems to be to use the add helper to concat the strings "-" with the integer as string, so it can be coerced back to a negative integer in a any consecutive calls to the add helper. This doesn't work however if the value is not a string, so that's where the stringformat helper comes in.
With string value
template posts.html (note how visible is explicitely passed as string - alternative below)
{% for post in posts %}
<h4>{{ post.title }}</h4>
...
{% include 'show_likes.html' with likes=post.likes visible="3" %}
{% endfor %}
template show_likes.html (note the add:0 to make the boolean operator work)
{% with show=visible|default:"2" %}
{% for like in likes %}
{% if forloop.counter <= show|add:0 %}
{% if not forloop.first %},{% endif %}
{{ like.username }}
{% endif %}
{% endfor %}
{% if likes|length > show|add:0 %}
{% with rest="-"|add:show %}
and {{ likes|length|add:rest }} more
{% endwith %}
{% endif %}
like this
{% endwith %}
Alternative with integer
You could just convert your integer to a string in the calling template using |stringformat:"d"
If however the number of visible items you want to show is an integer, you'll have to add a call to stringformat:"d" to have it converted to string
template posts.html
{% for post in posts %}
<h4>{{ post.title }}</h4>
...
{% include 'show_likes.html' with likes=post.likes visible=3 %}
{% endfor %}
template show_likes.html
{% with show=visible|default:2 %}
{% with show_str=show|stringformat:"d" %}
{% for like in likes %}
{% if forloop.counter <= show %}
{% if not forloop.first %},{% endif %}
{{ like.username }}
{% endif %}
{% endfor %}
{% if likes|length > show|add:0 %}
{% with rest="-"|add:show_str %}
and {{ likes|length|add:rest }} more
{% endwith %}
{% endif %}
{% endwith %}
{% endwith %}
Since I'm a very beginner with Django and Python, I'm pretty sure this approach is far worse than actually creating a custom helper! So I'm not suggesting anyone should be using this. This was just my attempt on trying to solve this with the available template helpers and without any custom stuff.
Hope this helps
Lo primero es multiplicar por -1 para convertirlo en una valor negativo y guardarlo en una variable y posterior a usar la suma
The first thing is to multiply by -1 to turn it into a negative value
and save it in a variable and then use the add
{% widthratio val2 1 -1 as result %}
{{result|add:val1}}
After search I found that I can make {% with var=value %} with filters to make the arithmetic operations "with other variables or not"
For example: I have x = 5 and y = 3 and need to add the y's value to x value, all what I need is these steps:
1- Create variable x : {% with x=5 %}
2- Create variable y : {% with y=3 %}
3- In my HTML tags, say <h1>, write that : <h1>{{ x|add:y }}</h1>
4- Close the y's with : {% endwith %}
5- Close the x's with : {% endwith %}
Hope it works with you, it worked with me.
{% with i=3 %}
{% with x=1 %}
<h1>{{i|add:x}}</h1> <!-- result is 4 -->
{% endwith %}
{% endwith %}
How do I write a numeric for loop in a Django template? I mean something like
for i = 1 to n
I've used a simple technique that works nicely for small cases with no special tags and no additional context. Sometimes this comes in handy
{% for i in '0123456789'|make_list %}
{{ forloop.counter }}
{% endfor %}
{% with ''|center:n as range %}
{% for _ in range %}
{{ forloop.counter }}
{% endfor %}
{% endwith %}
Unfortunately, that's not supported in the Django template language. There are a couple of suggestions, but they seem a little complex. I would just put a variable in the context:
...
render_to_response('foo.html', {..., 'range': range(10), ...}, ...)
...
and in the template:
{% for i in range %}
...
{% endfor %}
My take on this issue, i think is the most pythonic. Create a my_filters.py in your apps templatetags directory.
#register.filter(name='times')
def times(number):
return range(number)
Usage in your template:
{% load my_filters %}
{% for i in 15|times %}
<li>Item</li>
{% endfor %}
You can pass a binding of
{'n' : range(n) }
to the template, then do
{% for i in n %}
...
{% endfor %}
Note that you'll get 0-based behavior (0, 1, ... n-1).
(Updated for Python3 compatibility)
Maybe like this?
{% for i in "x"|rjust:"100" %}
...
{% endfor %}
I'm just taking the popular answer a bit further and making it more robust. This lets you specify any start point, so 0 or 1 for example. It also uses python's range feature where the end is one less so it can be used directly with list lengths for example.
#register.filter(name='range')
def filter_range(start, end):
return range(start, end)
Then in your template just include the above template tag file and use the following:
{% load myapp_filters %}
{% for c in 1|range:6 %}
{{ c }}
{% endfor %}
Now you can do 1-6 instead of just 0-6 or hard coding it. Adding a step would require a template tag, this should cover more uses cases so it's a step forward.
You can pass :
{ 'n' : range(n) }
To use template :
{% for i in n %}
...
{% endfor %}
I tried very hard on this question, and I find the best answer here:
(from how to loop 7 times in the django templates)
You can even access the idx!
views.py:
context['loop_times'] = range(1, 8)
html:
{% for i in loop_times %}
<option value={{ i }}>{{ i }}</option>
{% endfor %}
You don't pass n itself, but rather range(n) [the list of integers from 0 to n-1 included], from your view to your template, and in the latter you do {% for i in therange %} (if you absolutely insist on 1-based rather than the normal 0-based index you can use forloop.counter in the loop's body;-).
Just incase anyone else comes across this question… I've created a template tag which lets you create a range(...): http://www.djangosnippets.org/snippets/1926/
Accepts the same arguments as the 'range' builtin and creates a list containing
the result of 'range'.
Syntax:
{% mkrange [start,] stop[, step] as context_name %}
For example:
{% mkrange 5 10 2 as some_range %}
{% for i in some_range %}
{{ i }}: Something I want to repeat\n
{% endfor %}
Produces:
5: Something I want to repeat
7: Something I want to repeat
9: Something I want to repeat
You should use "slice" in template, a example like this:
in views.py
contexts = {
'ALL_STORES': Store.objects.all(),
}
return render_to_response('store_list.html', contexts, RequestContext(request, processors=[custom_processor]))
in store_list.html:
<ul>
{% for store in ALL_STORES|slice:":10" %}
<li class="store_item">{{ store.name }}</li>
{% endfor %}
</ul>
This method supports all the functionality of the standard range([start,] stop[, step]) function
<app>/templatetags/range.py
from django import template
register = template.Library()
#register.filter(name='range')
def _range(_min, args=None):
_max, _step = None, None
if args:
if not isinstance(args, int):
_max, _step = map(int, args.split(','))
else:
_max = args
args = filter(None, (_min, _max, _step))
return range(*args)
Usage:
{% load range %}
<p>stop 5
{% for value in 5|range %}
{{ value }}
{% endfor %}
</p>
<p>start 5 stop 10
{% for value in 5|range:10 %}
{{ value }}
{% endfor %}
</p>
<p>start 5 stop 10 step 2
{% for value in 5|range:"10,2" %}
{{ value }}
{% endfor %}
</p>
Output
<p>stop 5
0 1 2 3 4
</p>
<p>start 5 stop 10
5 6 7 8 9
</p>
<p>start 5 stop 10 step 2
5 7 9
</p>
This essentially requires a range function. A Django feature ticket was raised (https://code.djangoproject.com/ticket/13088) for this but closed as "won't fix" with the following comment.
My impression of this idea is that it is trying to lead to programming in the template. If you have a list of options that need to be rendered, they should be computed in the view, not in the template. If that's as simple as a range of values, then so be it.
They have a good point - Templates are supposed to be very simple representations of the view. You should create the limited required data in the view and pass to the template in the context.
{% for _ in ''|center:13 %}
{{ forloop.counter }}
{% endfor %}
If the number is coming from a model, I found this to be a nice patch to the model:
def iterableQuantity(self):
return range(self.quantity)
You can use:
{% with ''|center: i as range %}
For those who are looking to simple answer, just needing to display an amount of values, let say 3 from 100 posts for example just add {% for post in posts|slice:"3" %} and loop it normally and only 3 posts will be added.
This shows 1 to 20 numbers:
{% for i in "x"|rjust:"20"|make_list %}
{{ forloop.counter }}
{% endfor %}
also this can help you:
(count_all_slider_objects come from views)
{% for i in "x"|rjust:count_all_slider_objects %}
{{ forloop.counter }}
{% endfor %}
or
{% with counter=count_all_slider_objects %}
{% if list_all_slider_objects %}
{% for slide in list_all_slider_objects %}
{{forloop.counter|add:"-1"}}
{% endfor%}
{% endif %}
{% endwith %}
You can pass range(n) instead of n in the context in views.py. This will give you an iterable list.
context['range']= range(n)
Then you can iterate in your template this way:
{% for i in range %}
<!-- your code -->
{% endfor %}
{% for i in range(10) %}
{{ i }}
{% endfor %}