Is Wagtail's InlinePanel Compatible w/ a Non Page Model? - wagtail

Question

I have a wagtail non-Page model that I'd like to use an InlinePanel for so that I can edit multiple items inline in the parent form.
class Parent(ClusterableModel):
panels = [...,
InlinePanel('child_items')
]
class Child(Orderable):
value = models...
parent_value = ParentalKey('.Parent', on_delete=models.CASCADE, related_name='child_items')
But unfortunately the inline panel is not rendering in the wagtail admin UI.
From a quick glance at the code it seems like the InlinePanel requires a Page object/editor, so I thought I'd ask here if there is a way to use an InlinePanel on a non-Page object, or if there is a better way to achieve inline editing of objects (like django's StackedInline) in the wagtail admin for non-page objects.

Answer 1

InlinePanel does work on non-Page models if they are registered as snippets or through ModelAdmin. A working version of your code is (tested on a newly-created Wagtail project with home/models.py replaced with the code below):
from django.db import models
from modelcluster.fields import ParentalKey
from modelcluster.models import ClusterableModel
from wagtail.admin.edit_handlers import FieldPanel, InlinePanel
from wagtail.core.models import Page, Orderable
from wagtail.snippets.models import register_snippet
class HomePage(Page):
pass
#register_snippet
class Parent(ClusterableModel):
title = models.CharField(max_length=255)
panels = [
FieldPanel('title'),
InlinePanel('child_items', label='Child items'),
]
class Child(Orderable):
parent_value = ParentalKey(Parent, on_delete=models.CASCADE, related_name='child_items')
value = models.CharField(max_length=255)
panels = [
FieldPanel('value'),
]