Django形式与对象列表

Question

I have a problem to get back an object from a django form after submission.

I have an object list (filled with MyObject , not a django model) filled by another python package.

In models.py , I have :

class MyObjectForm(forms.Form):

    def __init__(self, *args, **kwargs):
        # Get the list
        myobjects = kwargs.pop('myobjects')
        super(MyObjectForm, self).__init__(*args, **kwargs)
        choices = [(o, o.name) for o in myobjects]
        self.fields["my_objects"] = forms.TypedChoiceField(choices=choices)

For information, the HTML looks OK.

In views.py , form.is_valid() is always False when I click on the submit button. Is there a problem ?

When I change models.py with :

self.fields["my_objects"] = forms.TypedChoiceField(choices=choices, required=False)

In views.py , form.is_valid() is True but I can't get back my objet MyObject (I get an empty value). Is that possible ? And if yes, how can I do that ?

Answer 1

Look at what you used as choices... MyObject instances, really ? How is a MyObject instance supposed to be sent to a browser as part of a HTML form and then back to your server thru a POST request body ?

If you have some persistant unique identifier for each of your MyObject instances, use this for your choices, ie

choices = [(o.some_stable_and_unique_id, o.name) for o in myobjects]

Note that it won't solve all of your issues... You'll then have to subclass TypedChoiceField to retrieve the object based on its "id" etc.