Use ExtensibleForm from mixins.py

aleksis/core/forms.py

@@ -5,65 +5,16 @@ from django import forms
 from django.contrib.auth import get_user_model
 from django.contrib.contenttypes.models import ContentType
 from django.core.exceptions import ValidationError
-from django.forms.models import ModelFormMetaclass
 from django.utils import timezone
 from django.utils.translation import ugettext_lazy as _
 
 from django_select2.forms import ModelSelect2MultipleWidget, Select2Widget
 from material import Layout, Fieldset, Row
-from material.base import LayoutNode
 
+from .mixins import ExtensibleForm
 from .models import Group, Person, School, SchoolTerm, Announcement, AnnouncementRecipient
 
 
-class ExtensibleFormMetaclass(ModelFormMetaclass):
-     def __new__(mcs, name, bases, dct):
-        x = super().__new__(mcs, name, bases, dct)
-
-        if hasattr(x, "layout"):
-            base_layout = x.layout.elements
-        else:
-            base_layout = []
-
-        x.base_layout = base_layout
-        x.layout = Layout(*base_layout)
-
-        return x
-
-
-class ExtensibleForm(forms.ModelForm, metaclass=ExtensibleFormMetaclass):
-    """ Base model for extensible forms
-
-    This mixin adds functionality which allows
-    - apps to add layout nodes to the layout used by django-material
-
-    Add layout nodes
-    ================
-
-    ```
-    from material import Fieldset
-
-    from aleksis.core.forms import ExampleForm
-
-    node = Fieldset("field_name")
-    ExampleForm.add_node_to_layout(node)
-    ```
-
-    """
-
-    @classmethod
-    def add_node_to_layout(cls, node: LayoutNode):
-        """
-        Add a node to `layout` attribute
-
-        :param node: django-material layout node (Fieldset, Row etc.)
-        :type node: LayoutNode
-        """
-
-        cls.base_layout.append(node)
-        cls.layout = Layout(*cls.base_layout)
-
-
 class PersonAccountForm(forms.ModelForm):
     class Meta:
         model = Person