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Python Customizing the Django Admin Customizing the List View Building Custom Filters

Guy Scorpion
Guy Scorpion
11,053 Points

How would I create a custom filter based on the created date of an item?

The video shows how to create a filter using years but it doesn't get this info from entries in the database.

Method shown in the video:

    def lookups(self, request, model_admin):
        return (
            ('2015', '2015'),
            ('2016', '2016'),
        )

    def queryset(self, request, queryset):
        years = [2015, 2016]
        for year in years:
            if self.value() == str(year):
                return queryset.filter(created_at__gte=date(year, 1, 1),
                                       created_at__lte=date(year, 12, 31))

How would I go about checking for entries, retrieving the year they were created, then using that as the lookup?

Steven Parker
Steven Parker
229,982 Points

:mailbox_with_mail: Hi, I got your message.

But I don't know Django (yet). I'll have to leave this one for someone else.

:bulb: The resource recommendation mechanism could be improved by checking for people who have answered questions on a particular topic before and/or have completed courses on those topics. Clearly, it needs to be more specific about the "topic" than just the language.

1 Answer

Alex Koumparos
seal-mask
.a{fill-rule:evenodd;}techdegree
Alex Koumparos
Python Development Techdegree Student 36,887 Points

Hi Guy,

You've probably figured this out for yourself by now, but for anyone else wondering the same thing. Here is a simple way you could achieve what you're looking for.

(I'm just replacing your lookups method, everything else is the same):

def lookups(self, request, model_admin):

        # 1. make a queryset of all the records in the DB
        objs = model_admin.model.objects.all()

        # 2. get just the created_at field
        dates = objs.values_list('created_at', flat=True)

        # 3. get just the years
        years = [d.year for d in dates]

        # 4. get the unique years
        years = set(years)

        # 5. sort it
        years = sorted(years)

        # 6. format as a valid lookup (the example is a tuple of tuples, but a list of tuples is valid too)
        lookup = [(y, y) for y in years]

        return lookup

Cheers,

Alex