django-nested-inline missing fields when adding new inline row - django

Question

In our project, i've been making use of the latest version of django-nested-inlines v0.3.7 with django 1.7
I have the following definition in my django admin to display the inlines
class SpecsGroupedContentInline(NestedStackedInline):
model = SpecificationGroupedContent
extra = 1
fk_name = "specification"
fields = ["field_unit"]
class SpecsContentInline(NestedStackedInline):
model = SpecificationListContent
extra = 1
fk_name = "specification"
fields = ["content"]
class SpecsInline(NestedStackedInline):
model = Specification
inlines = [SpecsContentInline, SpecsGroupedContentInline]
extra = 1
fk_name = "product"
class ProductAdmin(NestedModelAdmin):
inlines = [
SpecsInline
]
list_display = ('name', 'sku')
form = ProductAdminForm
When the page loads, the page looks like this
Initial product page load
It's a bit hard to see but the specs section has a title, an inline for Listed Contents and an inline for Grouped Contents. Afterwards, there's an empty Specs section with an empty title, empty Listed Contents, and empty Grouped Contents.
When I press the "Add another Specification" button at the bottom of the Specification inline to add a new row, the result of the new entry looks like this
New Specification entry image
As you can see, the Grouped Content field "Field Unit" is missing. I'm not sure if my setup is incorrect, but i found this stack overflow entry with a similar setup to mine
Django nested inlines not working?
It is for a different error though but we have a similar inline setup so i was thinking this setup is ok for django-nested-inlines.
Also, I'm sure if it's related but is django-nested-inlines affected if a nested inline model is a foreign key of another model? The SpecificationsGroupedContent model is a foreign key of another model unlike the SpecificationsListContent. I did a quick test where the SpecsInline inlines contained either SpecsGroupedContentInline only or SpecsContentInline only. It was working perfectly when using only SpecsContentInline but the error occurs when using SpecsGroupedContentInline.
For reference, here are the models I'm using with the related model for SpecsGroupedContent
class Product(AuthorStampedModel):
name = models.CharField(max_length=100)
sku = models.CharField(unique=True, max_length=100, verbose_name='SKU')
summary = models.TextField(blank=True, default="")
def __unicode__(self):
return self.return_product_details()
def return_product_details(self):
return '%s: %s' % (self.sku, self.name)
class Specification(models.Model):
product = models.ForeignKey('Product', related_name='specs')
title = models.CharField(max_length=100)
def __unicode__(self):
return self.return_spec_string()
def return_spec_string(self):
return '%s: %s' % (self.product.return_product_details(), self.title)
class SpecificationListContent(models.Model):
specification = models.ForeignKey('Specification', related_name='list_content')
content = models.CharField(max_length=255)
class Meta:
verbose_name_plural = 'Specification Listed Contents'
def __unicode__(self):
return self.specification.return_spec_string()
class SpecificationGroupedContent(models.Model):
specification = models.ForeignKey('Specification', related_name='group_content')
field_unit = models.CharField(max_length=255)
class Meta:
verbose_name_plural = 'Specification Grouped Contents'
def __unicode__(self):
return self.specification.return_spec_string()
class SpecificationGroupedContentValue(models.Model):
specification_grouped_content = models.ForeignKey(
'SpecificationGroupedContent',
related_name='group_content_value'
)
value = models.CharField(max_length=255)
class Meta:
verbose_name_plural = 'Specification Grouped Content Values'
def __unicode__(self):
return self.specification_grouped_content.specification.return_spec_string()
Thanks