How to show data in django template filtered by user criteria?

Question

Django

I learn django (and the web in general) by trial and error on a home project.
There is a simple model:

class CrArchive(models.Model):
    cr_id = models.IntegerField(primary_key=True)
    type = models.ForeignKey(CrType, db_index=True)   
    cr_description = models.TextField(blank=True)
    latitude = models.FloatField(blank=True)
    longitude = models.FloatField(blank=True)

    class Meta:
        managed = False
        db_table = 'cr_archive'

For reference, I wrote a view for her:

def index(request):
    latest_crime_list = CrArchive.objects.order_by('-cr_id')[:5]
    context = {'latest_crime_list': latest_crime_list, }
    return render(request, 'archive/archive.html', context)

And part of the template below it:

<div class="row">
        {% if latest_crime_list %}
            {% for crime in latest_crime_list %}
            <div class="col-md-12">
            	<div class="bs-callout bs-callout-warning">
            		<h4>{{ crime.latitude }} | {{ crime.longitude }}  | {{ crime.type }}</h4>
            		<p>{{ crime.cr_description }}</p>
            	</div>
            </div>
            {% endfor %}
        {% endif %}
  </div>

The last 5 records from cr_archive are displayed fine.
Now I decided to complicate the task. Suppose the user decides to display all records where latitude = 34.567 (the latitude value, for example, is entered in some component on the page). Here I have a plug. I don't really understand how to pass this filter to the model and filter the values ​​and how to remake the view. And how not to display anything if the filter search is not running? Please help.

Answer 1

Familiarize yourself with forms
https://docs.djangoproject.com/en/dev/topics/forms/
Get data, validate, then you can use this data as you like.
For example:
latest_crime_list = CrArchive.objects.filter(latitude=latitude).order_by('-cr_id')[:5]
As an option, if the coordinates are saved and you can choose from the existing ones instead of forcing the user to enter, then extract the parameter from the address:
url(r'^/places/latitude/(.+)', places_views.show_latitude),
and in views use this option.
Examples and docks shaft, write in detail vlom. If you want, put the project on bitbucket or github - it will be faster to show the code than to explain :)