admin: parameterise generic from's base template

passbook/admin/templates/generic/create.html

@@ -1,4 +1,4 @@
-{% extends "generic/form.html" %}
+{% extends base_template|default:"generic/form.html" %}
 
 {% load utils %}
 {% load i18n %}

passbook/admin/templates/generic/form.html

@@ -30,12 +30,12 @@
   <div class="">
     <form action="" method="post" class="form-horizontal">
       {% include 'partials/form.html' with form=form %}
+      {% block beneath_form %}
+      {% endblock %}
       <a class="btn btn-default" href="{% back %}">{% trans "Cancel" %}</a>
       <input type="submit" class="btn btn-primary" value="{% block action %}{% endblock %}" />
     </form>
   </div>
-  {% block beneath_form %}
-  {% endblock %}
   <script>
     const attributes = document.getElementsByName('attributes');
     if (attributes.length > 0) {

passbook/admin/templates/generic/update.html

@@ -1,4 +1,4 @@
-{% extends "generic/form.html" %}
+{% extends base_template|default:"generic/form.html" %}
 
 {% load utils %}
 {% load i18n %}

passbook/admin/views/property_mapping.py

@@ -66,6 +66,9 @@ class PropertyMappingCreateView(
             if x.__name__ == property_mapping_type
         )
         kwargs["type"] = model._meta.verbose_name
+        form_cls = self.get_form_class()
+        if hasattr(form_cls, "template_name"):
+            kwargs["base_template"] = form_cls.template_name
         return kwargs
 
     def get_form_class(self):
@@ -92,6 +95,12 @@ class PropertyMappingUpdateView(
     success_url = reverse_lazy("passbook_admin:property-mappings")
     success_message = _("Successfully updated Property Mapping")
 
+    def get_context_data(self, **kwargs):
+        form_cls = self.get_form_class()
+        if hasattr(form_cls, "template_name"):
+            kwargs["base_template"] = form_cls.template_name
+        return kwargs
+
     def get_form_class(self):
         form_class_path = self.get_object().form
         form_class = path_to_class(form_class_path)