I know there isn't MultipleChoiceField for a Model, you can only use it on Forms.

Today I face an issue when analyzing a new project related with Multiple Choices.

I would like to have a field like a CharField with choices with the option of multiple choice.

I solved this issue other times by creating a CharField and managed the multiple choices in the form with a forms.MultipleChoiceField and store the choices separated by commas.

In this project, due to configuration, I cannot do it as I mention above, I need to do it in the Models, and I prefer NOT to edit the Django admin form neither use forms. I need a Model Field with multiple choices option

• Have someone solved anything like this via Models ?

Maybe overriding some of the models function or using a custom widget... I don't know, I'm kinda lost here.

Edit

I'm aware off simple choices, I would like to have something like:

class MODEL(models.Model):
    MY_CHOICES = (
        ('a', 'Hola'),
        ('b', 'Hello'),
        ('c', 'Bonjour'),
        ('d', 'Boas'),
    )
    ...
    ...
    my_field = models.CharField(max_length=1, choices=MY_CHOICES)
    ...

but with the capability of saving multiple choices not only 1 choice.

Solution 1:

You need to think about how you are going to store the data at a database level. This will dictate your solution.

Presumably, you want a single column in a table that is storing multiple values. This will also force you to think about how you will serialize - for example, you can't simply do comma separated if you need to store strings that might contain commas.

However, you are probably best off using a solution like django-multiselectfield

Solution 2:

In case You are using Postgres consider using ArrayField.

from django.db import models
from django.contrib.postgres.fields import ArrayField

class WhateverModel(models.Model):
    WHATEVER_CHOICE = u'1'
    SAMPLE_CHOICES = (
        (WHATEVER_CHOICE, u'one'),
    )
    choices = ArrayField(
        models.CharField(choices=SAMPLE_CHOICES, max_length=2, blank=True, default=WHATEVER_CHOICE),
    )

Solution 3:

From the two, https://pypi.python.org/pypi/django-select-multiple-field/ looks more well rounded and complete. It even has a nice set of unittests.

The problem I found is that it throws a Django 1.10 deprecation warning in the class that implements the model field.

I fixed this and sent a PR. The latest code, until they merge my PR (if they ever decide to hehe) is in my fork of the repo, here: https://github.com/matiasherranz/django-select-multiple-field

Cheers!

M.-

Solution 4:

In Your Case, I used ManyToManyField

It Will be something like that:

class MY_CHOICES(models.Model)
    choice = models.CharField(max_length=154, unique=True)

class MODEL(models.Model):
    ...
    ...
    my_field = models.ManyToManyField(MY_CHOICES)

So, now you can select multiple choices