how to limit foreign key choices in the form page?

Question

below are my models, I want to display only those groups in post form in which the user is joined in. Example: if I joined in "mcu" group then only that group should be displayed, how should I do that??

GROUP MODEL

class Group(models.Model):
    name = models.CharField(max_length=200, unique=True)
    description = models.TextField(blank=True, default='')
    members = models.ManyToManyField(User, through='GroupMember')


class GroupMember(models.Model):
    group = models.ForeignKey(Group, related_name='memberships',on_delete=models.CASCADE)
    user = models.ForeignKey(User, related_name='user_groups',on_delete=models.CASCADE)

    class Meta:
        unique_together = ('group', 'user')

POST MODEL

User = get_user_model()

class Post(models.Model):
    user = models.ForeignKey(User, related_name='posts',on_delete=models.CASCADE)
    created_at = models.DateTimeField(auto_now=True)
    title = models.CharField(max_length=250,default='')
    message = RichTextField()
    group = models.ForeignKey(Group, related_name='posts', null=True, blank=True,on_delete=models.CASCADE)


    class Meta:
        ordering = ['-created_at']
        unique_together = ['user', 'message']

In views.py

class CreatePost(LoginRequiredMixin, SelectRelatedMixin, generic.CreateView):
    model = models.Post
    form_class = forms.PostForm

    def form_valid(self, form):
        self.object = form.save(commit=False)
        self.object.user = self.request.user
        self.object.save()
        return super().form_valid(form)

In forms.py

class PostForm(forms.ModelForm):
    class Meta:
        model = models.Post
        fields = ('title', 'message', 'group')
        widgets = {
            'message': forms.Textarea(attrs={'class': 'form-control mb-3'}),
            'title': forms.TextInput(attrs={'class': 'form-control mb-3'}),
            'group': forms.Select(attrs={'class': 'form-control'}),
        }

Please add the view and form class you have to the question. — Abdul Aziz Barkat
– Abdul Aziz Barkat, Commented Apr 7, 2021 at 12:39

F A · Accepted Answer · 2021-04-07 13:02:29Z

4

If would've been good if you would've published the views.py of the above form and forms.py where the form is created.

Without seeing the above two files, you would need to perform something like the following.

In your forms.py file, you would have a similar form as below. You need to add def __init__ to add the logic.

Example of the forms.py file-

from django import forms
from django.forms import ModelForm

class PostForm(ModelForm):
    class Meta:
        model = Post
        fields = ['title', 'message', 'group']

    def __init__(self, bundle_seller, *args, **kwargs):
        super(PostForm, self).__init__(*args, **kwargs)
        self.fields['group'].queryset = Group.objects.all().filter(members=loggedin_user)

The reference loggedin_user that you have referred in the last line above needs to be referred in the views.py file for Posts. I'm assuming you're using function-based view in the below example-

def new_post(request):
    ....
    loggedin_user = request.user
    form = PostForm(data=request.POST or None, loggedin_user=loggedin_user)
    if request.method == 'POST':
        ....
    else:
        form = PostForm(loggedin_user=loggedin_user)

Let me know in comments if the above helps.

answered Apr 7, 2021 at 13:02

F A

3482 silver badges12 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

pavan kumar Over a year ago

I've updated the question please check the question once again

pavan kumar Over a year ago

What is "bundle_seller" in init function of forms.py and What is self.fields['group'].queryset in forms.py

Collectives™ on Stack Overflow

how to limit foreign key choices in the form page?

1 Answer 1

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related