在 django 中使用表单集时，如何在内联中包含内联

Question

我想在我的表单集中应用具有表单案例 model 的情况，并在具有报价的内联中- 提供内联的 model也，游艇 - 游艇 Z20F35E630DAF44DBFA4C3F68F539 。

模型.py

class Case(models.Model):
    client=models.ForeignKey(Client,null=True,verbose_name="Client",on_delete = models.CASCADE)
    date_created = models.DateTimeField("Date of Case Creation", null=True,blank=True, default=datetime.datetime.now)
    comment = models.CharField("Comments",max_length=500, blank=True, null=True)

class Offer(models.Model):
    date_created = models.DateTimeField("Date of Offer creation", null=True,blank=True, default=datetime.datetime.now)
    notes=models.CharField("Offer Notes",max_length=100, blank=True)
    case=models.ForeignKey(Case,verbose_name="Case",on_delete = models.CASCADE)

class Yacht(models.Model):
    name = models.CharField(max_length=50, verbose_name="Name")
    price_per_day=models.DecimalField("Price(€) / Day", max_digits=8, decimal_places=2, default=0,blank=True)
    passengers = models.IntegerField("Passengers",blank=True,null=True)

class OfferHasYacht(models.Model):
    offer=models.ForeignKey(Offer,null=True,verbose_name="Offer",on_delete = models.CASCADE)
    yacht=models.ForeignKey(Yacht,null=True,verbose_name="Yacht",on_delete = models.CASCADE)

在 forms.py 中：

OfferOfferHasYachtFormSet=inlineformset_factory(Offer,OfferHasYacht,form=OfferHasYachtForm,extra=1)

以报价形式和内联报价HasYacht（不包括来自OfferHasYachtForm的报价）

class OfferHasYachtForm(ModelForm):

    yacht = ModelChoiceField(required=True,queryset=Yacht.objects.all(),widget=autocomplete.ModelSelect2(url='yacht-autocomplete'))

    class Meta:
        model = OfferHasYacht
        fields = ['yacht']


    def __init__(self, *args, **kwargs):
            super(OfferHasYachtForm, self).__init__(*args, **kwargs)
            self.fields['yacht'].label = "Choose Yacht"

但是在尝试声明表单集时：

CaseOfferHasYachtFormSet=inlineformset_factory(Case,OfferHasYacht,form=OfferHasYachtForm,extra=1)

django 抱怨说：

ValueError: 'intranet.OfferHasYacht' has no ForeignKey to 'intranet.Case'.

如何解决这个问题，以便我可以创建或更新具有报价（如内联）和每个报价都有游艇（如内联）的案例。