Question

 15 class Profile(models.Model):
 16     """
 17     User profile model
 18     """
 19     user = models.ForeignKey(User, unique=True)
 20     country = models.CharField('Country', blank=True, null=True, default='',\
 21                                max_length=50, choices=country_list())
 22     is_active = models.BooleanField("Email Activated")

I have a model like above with country set to blank=True, null=True.

However, in the form that is presented to the end user, I required the country field to be completed.

So I redefine the field in the Model Form like this to ‘force’ it to become required:

 77 class ProfileEditPersonalForm(forms.ModelForm):
 78 
 79     class Meta:
 80         model = Profile
 81         fields = ('email',
 82                   'sec_email',  
 83                   'image',
 84                   'first_name',
 85                   'middle_name',
 86                   'last_name',
 87                   'country',
 88                   'number',
 89                   'fax',)
 90 
 98     country =  forms.ChoiceField(label='Country', choices = country_list())

So the country field is just an example (there are tons of them). Is there a better more DRY way of doing this?

Answer 1

You can modify the fields in __init__ in the form. This is DRY since the label, queryset and everything else will be used from the model. This can also be useful for overriding other things (e.g. limiting querysets/choices, adding a help text, changing a label, …).

class ProfileEditPersonalForm(forms.ModelForm):    
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.fields['country'].required = True

    class Meta:
        model = Profile
        fields = (...)

Here is a blog post that describes the same "technique": http://collingrady.wordpress.com/2008/07/24/useful-form-tricks-in-django/