Use SVG icon instead of font icon in modeladmin index view

- This uses the same classes and tags than 'wagtailadmin/shared/header.html'
- constructs the <header> element and its children and blocks to that convention

CHANGELOG.txt

@@ -40,7 +40,7 @@ Changelog
  * Added the ability to customise the pre-filled Image title on upload and it now defaults to the filename without the file extension (LB Johnston)
  * Add support for Python 3.10 (Matt Westcott)
  * Introduce, `autocomplete`, a separate method which performs partial matching on specific autocomplete fields. This is useful for suggesting pages to the user in real-time as they type their query. (Karl Hobley, Matt Westcott)
- * Use SVG icons in StreamField buttons and headers (Jérôme Lebleu)
+ * Use SVG icons in modeladmin headers and StreamField buttons/headers (Jérôme Lebleu)
  * Add tags to existing Django registered checks (LB Johnston)
  * Upgrade admin frontend JS libraries jQuery to 3.6.0 and Modernizr to 2.8.3 (Fabien Le Frapper)
  * Fix: Delete button is now correct colour on snippets and modeladmin listings (Brandon Murch)

docs/releases/2.15.rst

@@ -56,7 +56,7 @@ Other features
  * Added the ability to customise the pre-filled Image title on upload and it now defaults to the filename without the file extension (LB Johnston)
  * Add support for Python 3.10 (Matt Westcott)
  * Introduce, ``autocomplete``, a separate method which performs partial matching on specific autocomplete fields. This is useful for suggesting pages to the user in real-time as they type their query. (Karl Hobley, Matt Westcott)
- * Use SVG icons in StreamField buttons and headers (Jérôme Lebleu)
+ * Use SVG icons in modeladmin headers and StreamField buttons/headers (Jérôme Lebleu)
  * Add tags to existing Django registered checks (LB Johnston)
  * Upgrade admin frontend JS libraries jQuery to 3.6.0 and Modernizr to 2.8.3 (Fabien Le Frapper)
 

wagtail/contrib/modeladmin/templates/modeladmin/index.html

@@ -15,15 +15,18 @@
 
 {% block content %}
     {% block header %}
-        <header class="nice-padding hasform">
-            <div class="row">
+        <header class="hasform">
+            {% block breadcrumb %}{% endblock %}
+            <div class="row nice-padding">
                 <div class="left header-left">
                     <div class="col header-title">
                         {% block h1 %}
-                        <h1 {% if view.header_icon %}class="icon icon-{{ view.header_icon }}"{% endif %}>
-                            {{ view.get_page_title }}
-                            {% include 'modeladmin/includes/result_count.html' %}
-                        </h1>
+                            <h1>
+                                {% if view.header_icon %}{% icon name=view.header_icon class_name="header-title-icon" %}{% endif %}
+                                {{ view.get_page_title }}
+                                {% if view.get_page_subtitle %} <span>{{ view.get_page_subtitle }}</span> {% endif %}
+                                {% include 'modeladmin/includes/result_count.html' %}
+                            </h1>
                         {% endblock %}
                     </div>
                     {% block search %}{% search_form %}{% endblock %}
@@ -47,6 +50,7 @@
                     </div>
                 {% endblock %}
             </div>
+            {% block extra_rows %}{% endblock %}
         </header>
     {% endblock %}