How to use RelatedFieldWidgetWrapper in django 3

Question

What should I put in rel and admin site? This is the field in my form:

tutor_temporal = forms.ModelChoiceField(
    queryset=Tutor_temporal.objects.all(),
    label='Tutor No Registrado', 
    required=False,
    widget=RelatedFieldWidgetWrapper(
        widget=forms.Select(attrs={'class': 'input is-small is-rounded'}),
        rel=Tutor_temporal._meta.get_field('id').rel,
        admin_site= admin_site
    )
)

The problem is that when I try that, throws this AttributeError: 'AutoField' object has no attribute 'rel', because apparently is deprecated.

user_10499867 · Answer

from django.contrib.admin import site as admin_site

def __init__(self, *args, **kwargs):
        super(TesisForm, self).__init__(*args, **kwargs)
      
        self.fields['tutor_temporal'].widget = (
           RelatedFieldWidgetWrapper( 
               self.fields['tutor_temporal'].widget,
               self.instance._meta.get_field('tutor_temporal').remote_field,            
               admin_site,
           )
       )

user_5322871 · Answer

I was stuck in a scenario which I overrode some fields in a ModelForm :

class VariationsForm(forms.ModelForm):
    """ Variations admin form """

    color = forms.ModelChoiceField(
        required=True,
        queryset=mdl.Color.objects.filter(
            is_active=True,),
        label='Color',
        empty_label="-----",
    )
    size = forms.ModelChoiceField(
        required=True,
        queryset=mdl.Size.objects.filter(
            is_active=True,),
        label='Talla / Medida',
        empty_label="-----"
    )

And the "add action button" never was displayed, so I started to search on the net about how to enable this feature and I found out that usually all generated fields are wrapped by the class: RelatedFieldWidgetWrapper https://github.com/django/django/blob/master/django/contrib/admin/widgets.py#L224,

As a part of the solution as previously shared above, I applied the wrapper to the fields that I early overrode :

    from django.contrib.admin import (
      widgets,
      site as admin_site
    )
    .....
    .....
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        # personalize choices
        for field in ["color", "size"]:
            self.fields[field].widget = widgets.RelatedFieldWidgetWrapper(
                self.fields[field].widget,
                self.instance._meta.get_field(field).remote_field,
                admin_site
            )

finally :

Best regards,

How to use RelatedFieldWidgetWrapper in django 3

2 Answers