Django custom forms for Admin deleting fields dynamically

Question

The problem is I have a model called Gift. And it has a boolean field 'giftbought' that I want to hide in admin interface when the object is being created and show it when it is being updated.

I tryed making a form, overriding init method like:

class GiftForm(forms.ModelForm):
    giftbought = forms.BooleanField(label=u"Bought?", required=False)

    class Meta:
        model = Gift

    def __init__(self, *args, **kwargs):
        super(GiftForm, self).__init__(*args, **kwargs)
        if not self.instance.pk:
            del self.fields['giftbought']

But it doesn't work for admin, like it is being said in: Remove fields from ModelForm

I thing I needed to make a class ModelAdmin, overriding get_form method, but I don't know how to check if I is_instance or not...

It would be something like:

class GiftAdmin(admin.ModelAdmin):
    model = Gift

    def get_form(self, request, obj=None, **kwargs):
        # that IF doesnt work!!!
        if not self.instance.pk:
            self.exclude = ('giftbought',)
        return super(GiftAdmin, self).get_form(request, obj=None, **kwargs)

admin.site.register(Gift, GiftAdmin)

Any hint?

Paulo Bu · Accepted Answer · 2013-07-10T02:51:02.450

0

Definitely your best bet is ModelAdmin. I think you got it right except for the if test.

You should be able to do it like this:

class GiftAdmin(admin.ModelAdmin):
    model = Gift

    def get_form(self, request, obj=None, **kwargs):
        self.exclude = []
        # self.instance.pk should be None if the object hasn't yet been persisted
        if obj is None:
            self.exclude.append('giftbought')
        return super(GiftAdmin, self).get_form(request, obj, **kwargs)

admin.site.register(Gift, GiftAdmin)

Notice there are minor changes to the method code. You should check the docs, I'm sure you'll find everything you need there.

Hope this helps!

edited Jul 10 '13 at 02:51

answered Jul 09 '13 at 02:18

Paulo Bu

29,294
6
74
73

Hello Paulo.. I tried that, and both inserting and updating, I get the error: 'GiftAdmin' object has no attribute 'pk' – staticdev Jul 09 '13 at 09:33
It makes sense, how about the way you got it first? self.instance.pk? – Paulo Bu Jul 09 '13 at 12:42
It worked just changing to "if obj is None"! self.instance doesn't exist either. – staticdev Jul 10 '13 at 01:07
I see, great, I'll modify the answer. – Paulo Bu Jul 10 '13 at 02:50

Django custom forms for Admin deleting fields dynamically

1 Answers1