Typo fix

2023-04-12 16:28:12 +02:00 · 2023-04-12 16:26:21 +02:00 · 2023-04-12 16:26:13 +02:00 · 2023-04-12 16:22:37 +02:00 · 2023-04-12 15:57:10 +02:00 · 2023-04-12 14:36:50 +02:00
40 changed files with 3962 additions and 706 deletions
--- a/demos/gtk-demo/listview_settings.c
+++ b/demos/gtk-demo/listview_settings.c
@@ -29,6 +29,7 @@ struct _SettingsKey
 enum {
  PROP_0,
  PROP_NAME,
+  PROP_SETTINGS,
  PROP_SUMMARY,
  PROP_DESCRIPTION,
  PROP_VALUE,
@@ -89,6 +90,10 @@ settings_key_get_property (GObject    *object,
      }
      break;

+    case PROP_SETTINGS:
+      g_value_set_object (value, self->settings);
+      break;
+
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
      break;
@@ -118,6 +123,8 @@ settings_key_class_init (SettingsKeyClass *klass)
    g_param_spec_string ("description", NULL, NULL, NULL, G_PARAM_READABLE);
  properties[PROP_NAME] =
    g_param_spec_string ("name", NULL, NULL, NULL, G_PARAM_READABLE);
+  properties[PROP_SETTINGS] =
+    g_param_spec_object ("settings", NULL, NULL, G_TYPE_SETTINGS, G_PARAM_READABLE);
  properties[PROP_SUMMARY] =
    g_param_spec_string ("summary", NULL, NULL, NULL, G_PARAM_READABLE);
  properties[PROP_VALUE] =
@@ -147,6 +154,23 @@ settings_key_new (GSettings          *settings,
  return result;
 }

+static char *
+settings_key_get_search_string (SettingsKey *self)
+{
+  char *schema, *result;
+
+  g_object_get (self->settings, "schema-id", &schema, NULL);
+
+  result = g_strconcat (g_settings_schema_key_get_name (self->key), " ",
+                        g_settings_schema_key_get_summary (self->key), " ",
+                        schema,
+                        NULL);
+
+  g_free (schema);
+
+  return result;
+}
+
 static void
 item_value_changed (GtkEditableLabel  *label,
                    GParamSpec        *pspec,
@@ -203,28 +227,16 @@ strvcmp (gconstpointer p1,
  return strcmp (*s1, *s2);
 }

-static GtkFilter *current_filter;
-
-static gboolean
-transform_settings_to_keys (GBinding     *binding,
-                            const GValue *from_value,
-                            GValue       *to_value,
-                            gpointer      data)
+static gpointer
+map_settings_to_keys (gpointer item,
+                      gpointer unused)
 {
-  GtkTreeListRow *treelistrow;
-  GSettings *settings;
+  GSettings *settings = item;
  GSettingsSchema *schema;
  GListStore *store;
-  GtkSortListModel *sort_model;
-  GtkFilterListModel *filter_model;
-  GtkFilter *filter;
  char **keys;
  guint i;

-  treelistrow = g_value_get_object (from_value);
-  if (treelistrow == NULL)
-    return TRUE;
-  settings = gtk_tree_list_row_get_item (treelistrow);
  g_object_get (settings, "settings-schema", &schema, NULL);

  store = g_list_store_new (SETTINGS_TYPE_KEY);
@@ -244,16 +256,7 @@ transform_settings_to_keys (GBinding     *binding,
  g_settings_schema_unref (schema);
  g_object_unref (settings);

-  sort_model = gtk_sort_list_model_new (G_LIST_MODEL (store),
-                                        g_object_ref (gtk_column_view_get_sorter (GTK_COLUMN_VIEW (data))));
-
-  filter = GTK_FILTER (gtk_string_filter_new (gtk_property_expression_new (SETTINGS_TYPE_KEY, NULL, "name")));
-  g_set_object (&current_filter, filter);
-  filter_model = gtk_filter_list_model_new (G_LIST_MODEL (sort_model), filter);
-
-  g_value_take_object (to_value, gtk_no_selection_new (G_LIST_MODEL (filter_model)));
-
-  return TRUE;
+  return store;
 }

 static GListModel *
@@ -310,24 +313,11 @@ search_enabled (GtkSearchEntry *entry)
  gtk_editable_set_text (GTK_EDITABLE (entry), "");
 }

-static void
-search_changed (GtkSearchEntry *entry,
-                gpointer data)
-{
-  const char *text = gtk_editable_get_text (GTK_EDITABLE (entry));
-
-  if (current_filter)
-    gtk_string_filter_set_search (GTK_STRING_FILTER (current_filter), text);
-}
-
 static void
 stop_search (GtkSearchEntry *entry,
             gpointer data)
 {
  gtk_editable_set_text (GTK_EDITABLE (entry), "");
-
-  if (current_filter)
-    gtk_string_filter_set_search (GTK_STRING_FILTER (current_filter), "");
 }

 static GtkWidget *window = NULL;
@@ -337,94 +327,53 @@ do_listview_settings (GtkWidget *do_widget)
 {
  if (window == NULL)
    {
-      GtkWidget *listview, *columnview;
+      GtkListView *listview;
      GListModel *model;
      GtkTreeListModel *treemodel;
-      GtkSingleSelection *selection;
+      GtkNoSelection *selection;
      GtkBuilderScope *scope;
      GtkBuilder *builder;
-      GtkColumnViewColumn *name_column;
-      GtkColumnViewColumn *type_column;
-      GtkColumnViewColumn *default_column;
-      GtkColumnViewColumn *summary_column;
-      GtkColumnViewColumn *description_column;
-      GtkSorter *sorter;
-      GActionGroup *actions;
-      GAction *action;
+      GError *error = NULL;
+      GtkFilter *filter;

      g_type_ensure (SETTINGS_TYPE_KEY);

      scope = gtk_builder_cscope_new ();
      gtk_builder_cscope_add_callback (scope, search_enabled);
-      gtk_builder_cscope_add_callback (scope, search_changed);
      gtk_builder_cscope_add_callback (scope, stop_search);
+      gtk_builder_cscope_add_callback (scope, settings_key_get_search_string);
      gtk_builder_cscope_add_callback (scope, item_value_changed);

      builder = gtk_builder_new ();
      gtk_builder_set_scope (builder, scope);
      g_object_unref (scope);

-      gtk_builder_add_from_resource (builder, "/listview_settings/listview_settings.ui", NULL);
+      gtk_builder_add_from_resource (builder, "/listview_settings/listview_settings.ui", &error);
+      g_assert_no_error (error);

      window = GTK_WIDGET (gtk_builder_get_object (builder, "window"));
      gtk_window_set_display (GTK_WINDOW (window),
                              gtk_widget_get_display (do_widget));
      g_object_add_weak_pointer (G_OBJECT (window), (gpointer *) &window);

-      listview = GTK_WIDGET (gtk_builder_get_object (builder, "listview"));
-      columnview = GTK_WIDGET (gtk_builder_get_object (builder, "columnview"));
-      type_column = GTK_COLUMN_VIEW_COLUMN (gtk_builder_get_object (builder, "type_column"));
-      default_column = GTK_COLUMN_VIEW_COLUMN (gtk_builder_get_object (builder, "default_column"));
-      summary_column = GTK_COLUMN_VIEW_COLUMN (gtk_builder_get_object (builder, "summary_column"));
-      description_column = GTK_COLUMN_VIEW_COLUMN (gtk_builder_get_object (builder, "description_column"));
-
-      actions = G_ACTION_GROUP (g_simple_action_group_new ());
-
-      action = G_ACTION (g_property_action_new ("show-type", type_column, "visible"));
-      g_action_map_add_action (G_ACTION_MAP (actions), action);
-      g_object_unref (action);
-
-      action = G_ACTION (g_property_action_new ("show-default", default_column, "visible"));
-      g_action_map_add_action (G_ACTION_MAP (actions), action);
-      g_object_unref (action);
-
-      action = G_ACTION (g_property_action_new ("show-summary", summary_column, "visible"));
-      g_action_map_add_action (G_ACTION_MAP (actions), action);
-      g_object_unref (action);
-
-      action = G_ACTION (g_property_action_new ("show-description", description_column, "visible"));
-      g_action_map_add_action (G_ACTION_MAP (actions), action);
-      g_object_unref (action);
-
-      gtk_widget_insert_action_group (columnview, "columnview", actions);
-      g_object_unref (actions);
+      listview = GTK_LIST_VIEW (gtk_builder_get_object (builder, "listview"));
+      filter = GTK_FILTER (gtk_builder_get_object (builder, "filter"));

      model = create_settings_model (NULL, NULL);
      treemodel = gtk_tree_list_model_new (model,
-                                           FALSE,
+                                           TRUE,
                                           TRUE,
                                           create_settings_model,
                                           NULL,
                                           NULL);
-      selection = gtk_single_selection_new (G_LIST_MODEL (treemodel));
-      g_object_bind_property_full (selection, "selected-item",
-                                   columnview, "model",
-                                   G_BINDING_SYNC_CREATE,
-                                   transform_settings_to_keys,
-                                   NULL,
-                                   columnview, NULL);
+      model = G_LIST_MODEL (gtk_map_list_model_new (G_LIST_MODEL (treemodel), map_settings_to_keys, NULL, NULL));
+      model = G_LIST_MODEL (gtk_flatten_list_model_new (model));
+      model = G_LIST_MODEL (gtk_filter_list_model_new (model, g_object_ref (filter)));
+      selection = gtk_no_selection_new (model);
+
      gtk_list_view_set_model (GTK_LIST_VIEW (listview), GTK_SELECTION_MODEL (selection));
      g_object_unref (selection);

-      name_column = GTK_COLUMN_VIEW_COLUMN (gtk_builder_get_object (builder, "name_column"));
-      sorter = GTK_SORTER (gtk_string_sorter_new (gtk_property_expression_new (SETTINGS_TYPE_KEY, NULL, "name")));
-      gtk_column_view_column_set_sorter (name_column, sorter);
-      g_object_unref (sorter);
-
-      sorter = GTK_SORTER (gtk_string_sorter_new (gtk_property_expression_new (SETTINGS_TYPE_KEY, NULL, "type")));
-      gtk_column_view_column_set_sorter (type_column, sorter);
-      g_object_unref (sorter);
-
      g_object_unref (builder);
    }

--- a/demos/gtk-demo/listview_settings.ui
+++ b/demos/gtk-demo/listview_settings.ui
@@ -1,5 +1,11 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <interface>
+  <object class="GtkStringFilter" id="filter">
+    <property name="expression">
+      <closure type="gchararray" function="settings_key_get_search_string" />
+    </property>
+    <property name="search" bind-source="entry" bind-property="text" />
+  </object>
  <object class="GtkWindow" id="window">
    <property name="title" translatable="yes">Settings</property>
    <property name="default-width">640</property>
@@ -14,15 +20,26 @@
      </object>
    </child>
    <child>
-      <object class="GtkPaned">
-        <property name="position">300</property>
+      <object class="GtkBox">
+        <property name="orientation">vertical</property>
+        <child>
+          <object class="GtkSearchBar">
+            <property name="search-mode-enabled" bind-source="search_button" bind-property="active" bind-flags="bidirectional"/>
+            <signal name="notify::search-mode-enabled" handler="search_enabled" object="entry"/>
+            <child>
+              <object class="GtkSearchEntry" id="entry">
+                <signal name="stop-search" handler="stop_search"/>
+              </object>
+            </child>
+          </object>
+        </child>
        <child>
          <object class="GtkScrolledWindow">
            <child>
              <object class="GtkListView" id="listview">
-                <property name="tab-behavior">item</property>
+                <property name="vexpand">1</property>
                <style>
-                  <class name="navigation-sidebar"/>
+                  <class name="rich-list"/>
                </style>
                <property name="factory">
                  <object class="GtkBuilderListItemFactory">
@@ -31,20 +48,71 @@
 <interface>
  <template class="GtkListItem">
    <property name="child">
-      <object class="GtkTreeExpander" id="expander">
-        <binding name="list-row">
-          <lookup name="item">GtkListItem</lookup>
-        </binding>
-        <property name="child">
-          <object class="GtkLabel">
-            <property name="xalign">0</property>
-            <binding name="label">
-              <lookup name="schema" type="GSettings">
-                <lookup name="item">expander</lookup>
+      <object class="GtkBox">
+        <child>
+          <object class="GtkBox">
+            <property name="orientation">vertical</property>
+            <child>
+              <object class="GtkLabel">
+                <property name="xalign">0</property>
+                <binding name="label">
+                  <lookup name="name" type="SettingsKey">
+                    <lookup name="item">GtkListItem</lookup>
+                  </lookup>
+                </binding>
+              </object>
+            </child>
+            <child>
+              <object class="GtkLabel">
+                <style>
+                  <class name="dim-label"/>
+                </style>
+                <property name="xalign">0</property>
+                <property name="ellipsize">end</property>
+                <binding name="label">
+                  <lookup name="summary" type="SettingsKey">
+                    <lookup name="item">GtkListItem</lookup>
+                  </lookup>
+                </binding>
+              </object>
+            </child>
+          </object>
+        </child>
+        <child>
+          <object class="GtkEntry">
+            <property name="hexpand">1</property>
+            <property name="halign">end</property>
+            <binding name="text">
+              <lookup name="value" type="SettingsKey">
+                <lookup name="item">GtkListItem</lookup>
              </lookup>
            </binding>
+            <signal name="notify::label" handler="item_value_changed"/>
          </object>
-        </property>
+        </child>
+      </object>
+    </property>
+  </template>
+</interface>
+                    ]]></property>
+                  </object>
+                </property>
+                <property name="header-factory">
+                  <object class="GtkBuilderListItemFactory">
+                    <property name="bytes"><![CDATA[
+<?xml version="1.0" encoding="UTF-8"?>
+<interface>
+  <template class="GtkListHeader">
+    <property name="child">
+      <object class="GtkLabel">
+        <property name="xalign">0</property>
+        <binding name="label">
+          <lookup name="schema" type="GSettings">
+            <lookup name="settings" type="SettingsKey">
+              <lookup name="item">GtkListHeader</lookup>
+            </lookup>
+          </lookup>
+        </binding>
      </object>
    </property>
  </template>
@@ -56,232 +124,7 @@
            </child>
          </object>
        </child>
-        <child>
-          <object class="GtkBox">
-            <property name="orientation">vertical</property>
-            <child>
-              <object class="GtkSearchBar">
-                <property name="search-mode-enabled" bind-source="search_button" bind-property="active" bind-flags="bidirectional"/>
-                <signal name="notify::search-mode-enabled" handler="search_enabled" object="entry"/>
-                <child>
-                  <object class="GtkSearchEntry" id="entry">
-                    <signal name="search-changed" handler="search_changed"/>
-                    <signal name="stop-search" handler="stop_search"/>
-                  </object>
-                </child>
-              </object>
-            </child>
-            <child>
-              <object class="GtkScrolledWindow">
-                <property name="hexpand">1</property>
-                <property name="vexpand">1</property>
-                <child>
-                  <object class="GtkColumnView" id="columnview">
-                    <property name="tab-behavior">cell</property>
-                    <style>
-                      <class name="data-table"/>
-                    </style>
-                    <child>
-                      <object class="GtkColumnViewColumn" id="name_column">
-                        <property name="title">Name</property>
-                        <property name="header-menu">header_menu</property>
-                        <property name="factory">
-                          <object class="GtkBuilderListItemFactory">
-                            <property name="bytes"><![CDATA[
-<?xml version="1.0" encoding="UTF-8"?>
-<interface>
-  <template class="GtkColumnViewCell">
-    <property name="child">
-      <object class="GtkLabel">
-        <property name="xalign">0</property>
-        <binding name="label">
-          <lookup name="name" type="SettingsKey">
-            <lookup name="item">GtkColumnViewCell</lookup>
-          </lookup>
-        </binding>
-      </object>
-    </property>
-  </template>
-</interface>
-                        ]]></property>
-                          </object>
-                        </property>
-                      </object>
-                    </child>
-                    <child>
-                      <object class="GtkColumnViewColumn">
-                        <property name="title">Value</property>
-                        <property name="resizable">1</property>
-                        <property name="header-menu">header_menu</property>
-                        <property name="factory">
-                          <object class="GtkBuilderListItemFactory">
-                            <property name="bytes"><![CDATA[
-<?xml version="1.0" encoding="UTF-8"?>
-<interface>
-  <template class="GtkColumnViewCell">
-    <property name="child">
-      <object class="GtkEditableLabel">
-        <binding name="text">
-          <lookup name="value" type="SettingsKey">
-            <lookup name="item">GtkColumnViewCell</lookup>
-          </lookup>
-        </binding>
-        <signal name="notify::label" handler="item_value_changed"/>
-      </object>
-    </property>
-  </template>
-</interface>
-                        ]]></property>
-                          </object>
-                        </property>
-                      </object>
-                    </child>
-                    <child>
-                      <object class="GtkColumnViewColumn" id="type_column">
-                        <property name="title">Type</property>
-                        <property name="resizable">1</property>
-                        <property name="header-menu">header_menu</property>
-                        <property name="factory">
-                          <object class="GtkBuilderListItemFactory">
-                            <property name="bytes"><![CDATA[
-<?xml version="1.0" encoding="UTF-8"?>
-<interface>
-  <template class="GtkColumnViewCell">
-    <property name="child">
-      <object class="GtkLabel">
-        <property name="xalign">0</property>
-        <binding name="label">
-          <lookup name="type" type="SettingsKey">
-            <lookup name="item">GtkColumnViewCell</lookup>
-          </lookup>
-        </binding>
-      </object>
-    </property>
-  </template>
-</interface>
-                        ]]></property>
-                          </object>
-                        </property>
-                      </object>
-                    </child>
-                    <child>
-                      <object class="GtkColumnViewColumn" id="default_column">
-                        <property name="title">Default</property>
-                        <property name="resizable">1</property>
-                        <property name="expand">1</property>
-                        <property name="header-menu">header_menu</property>
-                        <property name="factory">
-                          <object class="GtkBuilderListItemFactory">
-                            <property name="bytes"><![CDATA[
-<?xml version="1.0" encoding="UTF-8"?>
-<interface>
-  <template class="GtkColumnViewCell">
-    <property name="child">
-      <object class="GtkLabel">
-        <property name="xalign">0</property>
-        <binding name="label">
-          <lookup name="default-value" type="SettingsKey">
-            <lookup name="item">GtkColumnViewCell</lookup>
-          </lookup>
-        </binding>
-      </object>
-    </property>
-  </template>
-</interface>
-                        ]]></property>
-                          </object>
-                        </property>
-                      </object>
-                    </child>
-                    <child>
-                      <object class="GtkColumnViewColumn" id="summary_column">
-                        <property name="title">Summary</property>
-                        <property name="resizable">1</property>
-                        <property name="visible">0</property>
-                        <property name="expand">1</property>
-                        <property name="header-menu">header_menu</property>
-                        <property name="factory">
-                          <object class="GtkBuilderListItemFactory">
-                            <property name="bytes"><![CDATA[
-<?xml version="1.0" encoding="UTF-8"?>
-<interface>
-  <template class="GtkColumnViewCell">
-    <property name="child">
-      <object class="GtkLabel">
-        <property name="xalign">0</property>
-        <property name="wrap">1</property>
-        <binding name="label">
-          <lookup name="summary" type="SettingsKey">
-            <lookup name="item">GtkColumnViewCell</lookup>
-          </lookup>
-        </binding>
-      </object>
-    </property>
-  </template>
-</interface>
-                        ]]></property>
-                          </object>
-                        </property>
-                      </object>
-                    </child>
-                    <child>
-                      <object class="GtkColumnViewColumn" id="description_column">
-                        <property name="title">Description</property>
-                        <property name="resizable">1</property>
-                        <property name="visible">0</property>
-                        <property name="expand">1</property>
-                        <property name="header-menu">header_menu</property>
-                        <property name="factory">
-                          <object class="GtkBuilderListItemFactory">
-                            <property name="bytes"><![CDATA[
-<?xml version="1.0" encoding="UTF-8"?>
-<interface>
-  <template class="GtkColumnViewCell">
-    <property name="child">
-      <object class="GtkLabel">
-        <property name="xalign">0</property>
-        <property name="wrap">1</property>
-        <binding name="label">
-          <lookup name="description" type="SettingsKey">
-            <lookup name="item">GtkColumnViewCell</lookup>
-          </lookup>
-        </binding>
-      </object>
-    </property>
-  </template>
-</interface>
-                        ]]></property>
-                          </object>
-                        </property>
-                      </object>
-                    </child>
-                  </object>
-                </child>
-              </object>
-            </child>
-          </object>
-        </child>
      </object>
    </child>
  </object>
-  <menu id="header_menu">
-    <section>
-      <item>
-        <attribute name="label" translatable="yes">Type</attribute>
-        <attribute name="action">columnview.show-type</attribute>
-      </item>
-      <item>
-        <attribute name="label" translatable="yes">Default value</attribute>
-        <attribute name="action">columnview.show-default</attribute>
-      </item>
-      <item>
-        <attribute name="label" translatable="yes">Summary</attribute>
-        <attribute name="action">columnview.show-summary</attribute>
-      </item>
-      <item>
-        <attribute name="label" translatable="yes">Description</attribute>
-        <attribute name="action">columnview.show-description</attribute>
-      </item>
-    </section>
-  </menu>
 </interface>
--- a/demos/gtk-demo/listview_ucd.c
+++ b/demos/gtk-demo/listview_ucd.c
@@ -63,6 +63,19 @@ ucd_item_get_name (UcdItem *item)
  return item->name;
 }

+static int
+compare_script (gconstpointer a, gconstpointer b, gpointer data)
+{
+  const UcdItem *ai = a;
+  const UcdItem *bi = b;
+  int s1, s2;
+
+  s1 = (int) g_unichar_get_script (ai->codepoint);
+  s2 = (int) g_unichar_get_script (bi->codepoint);
+
+  return s2 - s1;
+}
+
 static GListModel *
 ucd_model_new (void)
 {
@@ -72,6 +85,7 @@ ucd_model_new (void)
  GListStore *store;
  guint u;
  char *name;
+  GtkSortListModel *sortmodel;

  bytes = g_resources_lookup_data ("/listview_ucd_data/ucdnames.data", 0, NULL);
  v = g_variant_ref_sink (g_variant_new_from_bytes (G_VARIANT_TYPE ("a(us)"), bytes, TRUE));
@@ -93,7 +107,10 @@ ucd_model_new (void)
  g_variant_unref (v);
  g_bytes_unref (bytes);

-  return G_LIST_MODEL (store);
+  sortmodel = gtk_sort_list_model_new (G_LIST_MODEL (store), NULL);
+  gtk_sort_list_model_set_section_sorter (sortmodel, GTK_SORTER (gtk_custom_sorter_new (compare_script, NULL, NULL)));
+
+  return G_LIST_MODEL (sortmodel);
 }

 static void
@@ -223,6 +240,16 @@ bind_combining_class (GtkSignalListItemFactory *factory,
  gtk_label_set_label (GTK_LABEL (label), get_combining_class_name (g_unichar_combining_class (codepoint)));
 }

+static void
+setup_header (GtkSignalListItemFactory *factory,
+              GObject                  *listitem)
+{
+  GtkWidget *label;
+  label = gtk_label_new ("");
+  gtk_label_set_xalign (GTK_LABEL (label), 0);
+  gtk_list_header_set_child (GTK_LIST_HEADER (listitem), label);
+}
+
 static void
 bind_script (GtkSignalListItemFactory *factory,
             GObject                  *listitem)
@@ -232,8 +259,8 @@ bind_script (GtkSignalListItemFactory *factory,
  gunichar codepoint;
  GUnicodeScript script;

-  label = gtk_list_item_get_child (GTK_LIST_ITEM (listitem));
-  item = gtk_list_item_get_item (GTK_LIST_ITEM (listitem));
+  label = gtk_list_header_get_child (GTK_LIST_HEADER (listitem));
+  item = gtk_list_header_get_item (GTK_LIST_HEADER (listitem));
  codepoint = ucd_item_get_codepoint (UCD_ITEM (item));
  script = g_unichar_get_script (codepoint);

@@ -325,12 +352,10 @@ create_ucd_view (GtkWidget *label)
  g_object_unref (column);

  factory = gtk_signal_list_item_factory_new ();
-  g_signal_connect (factory, "setup", G_CALLBACK (setup_label), NULL);
+  g_signal_connect (factory, "setup", G_CALLBACK (setup_header), NULL);
  g_signal_connect (factory, "bind", G_CALLBACK (bind_script), NULL);
-  column = gtk_column_view_column_new ("Script", factory);
-  gtk_column_view_column_set_resizable (column, TRUE);
-  gtk_column_view_append_column (GTK_COLUMN_VIEW (cv), column);
-  g_object_unref (column);
+  gtk_column_view_set_header_factory (GTK_COLUMN_VIEW (cv), factory);
+  g_object_unref (factory);

  return cv;
 }
--- a/gtk/gtk.h
+++ b/gtk/gtk.h
@@ -174,6 +174,7 @@
 #include <gtk/gtklistbase.h>
 #include <gtk/gtklinkbutton.h>
 #include <gtk/gtklistbox.h>
+#include <gtk/gtklistheader.h>
 #include <gtk/gtklistitem.h>
 #include <gtk/gtklistitemfactory.h>
 #include <gtk/deprecated/gtkliststore.h>
@@ -225,6 +226,7 @@
 #include <gtk/gtkscrolledwindow.h>
 #include <gtk/gtksearchbar.h>
 #include <gtk/gtksearchentry.h>
+#include <gtk/gtksectionmodel.h>
 #include <gtk/gtkselectionfiltermodel.h>
 #include <gtk/gtkselectionmodel.h>
 #include <gtk/gtkseparator.h>
--- a/gtk/gtkcolumnview.c
+++ b/gtk/gtkcolumnview.c
@@ -220,6 +220,7 @@ enum
  PROP_COLUMNS,
  PROP_ENABLE_RUBBERBAND,
  PROP_HADJUSTMENT,
+  PROP_HEADER_FACTORY,
  PROP_HSCROLL_POLICY,
  PROP_MODEL,
  PROP_REORDERABLE,
@@ -628,6 +629,10 @@ gtk_column_view_get_property (GObject    *object,
      g_value_set_object (value, self->hadjustment);
      break;

+    case PROP_HEADER_FACTORY:
+      g_value_set_object (value, gtk_column_view_get_header_factory (self));
+      break;
+
    case PROP_HSCROLL_POLICY:
      g_value_set_enum (value, gtk_scrollable_get_hscroll_policy (GTK_SCROLLABLE (self->listview)));
      break;
@@ -711,6 +716,10 @@ gtk_column_view_set_property (GObject      *object,
        }
      break;

+    case PROP_HEADER_FACTORY:
+      gtk_column_view_set_header_factory (self, g_value_get_object (value));
+      break;
+
    case PROP_HSCROLL_POLICY:
      if (gtk_scrollable_get_hscroll_policy (GTK_SCROLLABLE (self->listview)) != g_value_get_enum (value))
        {
@@ -825,6 +834,18 @@ gtk_column_view_class_init (GtkColumnViewClass *klass)
                          FALSE,
                          G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY);

+  /**
+   * GtkColumnView:header-factory: (attributes org.gtk.Property.get=gtk_column_view_get_header_factory org.gtk.Property.set=gtk_column_view_set_header_factory)
+   *
+   * The factory used for creating section headers.
+   *
+   * Since: 4.12
+   */
+  properties[PROP_HEADER_FACTORY] =
+    g_param_spec_object ("header-factory", NULL, NULL,
+                         GTK_TYPE_LIST_ITEM_FACTORY,
+                         G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
  /**
   * GtkColumnView:model: (attributes org.gtk.Property.get=gtk_column_view_get_model org.gtk.Property.set=gtk_column_view_set_model)
   *
@@ -2018,6 +2039,49 @@ gtk_column_view_get_enable_rubberband (GtkColumnView *self)
  return gtk_list_view_get_enable_rubberband (self->listview);
 }

+/**
+ * gtk_column_view_set_header_factory: (attributes org.gtk.Method.set_property=header-factory)
+ * @self: a `GtkColumnView`
+ * @factory: (nullable): The header factory
+ *
+ * Sets the factory used for creating seciton headers.
+ *
+ * If this factory is not set - which is the default - then no headers will be used.
+ *
+ * Since: 4.12
+ */
+void
+gtk_column_view_set_header_factory (GtkColumnView      *self,
+                                    GtkListItemFactory *factory)
+{
+  g_return_if_fail (GTK_IS_COLUMN_VIEW (self));
+
+  if (factory == gtk_list_view_get_header_factory (self->listview))
+    return;
+
+  gtk_list_view_set_header_factory (self->listview, factory);
+
+  g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_HEADER_FACTORY]);
+}
+
+/**
+ * gtk_column_view_get_header_factory: (attributes org.gtk.Method.get_property=header-factory)
+ * @self: a `GtkColumnView`
+ *
+ * Gets the factory set via [method@Gtk.ColumnView.set_header_factory].
+ *
+ * Returns: (nullable) (transfer none): The factory
+ *
+ * Since: 4.12
+ */
+GtkListItemFactory *
+gtk_column_view_get_header_factory (GtkColumnView *self)
+{
+  g_return_val_if_fail (GTK_IS_COLUMN_VIEW (self), NULL);
+
+  return gtk_list_view_get_header_factory (self->listview);
+}
+
 /**
 * gtk_column_view_set_row_factory: (attributes org.gtk.Method.set_property=row-factory)
 * @self: a `GtkColumnView`
@@ -2060,7 +2124,7 @@ gtk_column_view_set_row_factory (GtkColumnView      *self,
 GtkListItemFactory *
 gtk_column_view_get_row_factory (GtkColumnView *self)
 {
-  g_return_val_if_fail (GTK_IS_COLUMN_VIEW (self), FALSE);
+  g_return_val_if_fail (GTK_IS_COLUMN_VIEW (self), NULL);

  return gtk_list_view_get_factory (self->listview);
 }
--- a/gtk/gtkcolumnview.h
+++ b/gtk/gtkcolumnview.h
@@ -122,5 +122,12 @@ GDK_AVAILABLE_IN_4_12
 GtkListItemFactory *
                gtk_column_view_get_row_factory                 (GtkColumnView          *self);

+GDK_AVAILABLE_IN_4_12
+void            gtk_column_view_set_header_factory              (GtkColumnView          *self,
+                                                                 GtkListItemFactory     *factory);
+GDK_AVAILABLE_IN_4_12
+GtkListItemFactory *
+                gtk_column_view_get_header_factory              (GtkColumnView          *self);
+
 G_END_DECLS

--- a/gtk/gtkfilterlistmodel.c
+++ b/gtk/gtkfilterlistmodel.c
@@ -23,6 +23,7 @@

 #include "gtkbitset.h"
 #include "gtkprivate.h"
+#include "gtksectionmodelprivate.h"

 /**
 * GtkFilterListModel:
@@ -135,8 +136,67 @@ gtk_filter_list_model_model_init (GListModelInterface *iface)
  iface->get_item = gtk_filter_list_model_get_item;
 }

+static void
+gtk_filter_list_model_get_section (GtkSectionModel *model,
+                                   guint            position,
+                                   guint           *out_start,
+                                   guint           *out_end)
+{
+  GtkFilterListModel *self = GTK_FILTER_LIST_MODEL (model);
+  guint n_items;
+  guint pos, start, end;
+
+  switch (self->strictness)
+    {
+    case GTK_FILTER_MATCH_NONE:
+      *out_start = 0;
+      *out_end = G_MAXUINT;
+      return;
+
+    case GTK_FILTER_MATCH_ALL:
+      gtk_list_model_get_section (self->model, position, out_start, out_end);
+      return;
+
+    case GTK_FILTER_MATCH_SOME:
+      n_items = gtk_bitset_get_size (self->matches);
+      if (position >= n_items)
+        {
+          *out_start = n_items;
+          *out_end = G_MAXUINT;
+          return;
+        }
+      if (!GTK_IS_SECTION_MODEL (self->model))
+        {
+          *out_start = 0;
+          *out_end = n_items;
+          return;
+        }
+      break;
+
+    default:
+      g_assert_not_reached ();
+    }
+
+  /* if we get here, we have a section model, and are MATCH_SOME */
+
+  pos = gtk_bitset_get_nth (self->matches, position);
+  gtk_section_model_get_section (GTK_SECTION_MODEL (self->model), pos, &start, &end);
+  if (start == 0)
+    *out_start = 0;
+  else
+    *out_start = gtk_bitset_get_size_in_range (self->matches, 0, start - 1);
+  *out_end = *out_start + gtk_bitset_get_size_in_range (self->matches, start, end - 1);
+}
+
+static void
+gtk_filter_list_model_section_model_init (GtkSectionModelInterface *iface)
+{
+  iface->get_section = gtk_filter_list_model_get_section;
+}
+
 G_DEFINE_TYPE_WITH_CODE (GtkFilterListModel, gtk_filter_list_model, G_TYPE_OBJECT,
-                         G_IMPLEMENT_INTERFACE (G_TYPE_LIST_MODEL, gtk_filter_list_model_model_init))
+                         G_IMPLEMENT_INTERFACE (G_TYPE_LIST_MODEL, gtk_filter_list_model_model_init)
+                         G_IMPLEMENT_INTERFACE (GTK_TYPE_SECTION_MODEL, gtk_filter_list_model_section_model_init))

 static gboolean
 gtk_filter_list_model_run_filter_on_item (GtkFilterListModel *self,
@@ -164,7 +224,7 @@ gtk_filter_list_model_run_filter (GtkFilterListModel *self,
  gboolean more;

  g_return_if_fail (GTK_IS_FILTER_LIST_MODEL (self));
-  
+
  if (self->pending == NULL)
    return;

@@ -355,7 +415,7 @@ gtk_filter_list_model_set_property (GObject      *object,
    }
 }

-static void 
+static void
 gtk_filter_list_model_get_property (GObject     *object,
                                    guint        prop_id,
                                    GValue      *value,
@@ -503,7 +563,7 @@ gtk_filter_list_model_refilter (GtkFilterListModel *self,
    case GTK_FILTER_MATCH_SOME:
      {
        GtkBitset *old, *pending;
-      
+
        if (self->matches == NULL)
          {
            if (self->strictness == GTK_FILTER_MATCH_ALL)
--- a/gtk/gtkflattenlistmodel.c
+++ b/gtk/gtkflattenlistmodel.c
@@ -21,8 +21,8 @@

 #include "gtkflattenlistmodel.h"

+#include "gtksectionmodel.h"
 #include "gtkrbtreeprivate.h"
-#include "gtkprivate.h"

 /**
 * GtkFlattenListModel:
@@ -200,8 +200,39 @@ gtk_flatten_list_model_model_init (GListModelInterface *iface)
  iface->get_item = gtk_flatten_list_model_get_item;
 }

+static void
+gtk_flatten_list_model_get_section (GtkSectionModel *model,
+                                    guint            position,
+                                    guint           *out_start,
+                                    guint           *out_end)
+{
+  GtkFlattenListModel *self = GTK_FLATTEN_LIST_MODEL (model);
+  FlattenNode *node;
+  guint model_pos;
+
+  node = gtk_flatten_list_model_get_nth (self->items, position, &model_pos);
+  if (node == NULL)
+    {
+      *out_start = gtk_flatten_list_model_get_n_items (G_LIST_MODEL (self));
+      *out_end = G_MAXUINT;
+      return;
+    }
+
+  *out_start = position - model_pos;
+  *out_end = position - model_pos + g_list_model_get_n_items (node->model);
+}
+
+static void
+gtk_flatten_list_model_section_model_init (GtkSectionModelInterface *iface)
+{
+  iface->get_section = gtk_flatten_list_model_get_section;
+}
+
 G_DEFINE_TYPE_WITH_CODE (GtkFlattenListModel, gtk_flatten_list_model, G_TYPE_OBJECT,
-                         G_IMPLEMENT_INTERFACE (G_TYPE_LIST_MODEL, gtk_flatten_list_model_model_init))
+                         G_IMPLEMENT_INTERFACE (G_TYPE_LIST_MODEL,
+                                                gtk_flatten_list_model_model_init)
+                         G_IMPLEMENT_INTERFACE (GTK_TYPE_SECTION_MODEL,
+                                                gtk_flatten_list_model_section_model_init))

 static void
 gtk_flatten_list_model_items_changed_cb (GListModel *model,
@@ -433,7 +464,7 @@ gtk_flatten_list_model_class_init (GtkFlattenListModelClass *class)
  properties[PROP_MODEL] =
      g_param_spec_object ("model", NULL, NULL,
                           G_TYPE_LIST_MODEL,
-                           GTK_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY);
+                           G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);

  /**
   * GtkFlattenListModel:n-items:
--- a/gtk/gtkgridview.c
+++ b/gtk/gtkgridview.c
@@ -886,7 +886,7 @@ gtk_grid_view_size_allocate (GtkWidget *widget,
    {
      GtkListTile *filler;
      tile = gtk_list_item_manager_get_last (self->item_manager);
-      filler = gtk_list_tile_split (self->item_manager, tile, tile->n_items);
+      filler = gtk_list_tile_append_filler (self->item_manager, tile);
      gtk_list_tile_set_area_position (self->item_manager,
                                       filler,
                                       column_start (self, xspacing, i),
--- a/gtk/gtklistbase.c
+++ b/gtk/gtklistbase.c
@@ -1954,11 +1954,25 @@ gtk_list_base_split_func (GtkWidget   *widget,
 }

 static GtkListItemBase *
-gtk_list_base_create_widget_func (GtkWidget *widget)
+gtk_list_base_create_list_widget_func (GtkWidget *widget)
 {
  return GTK_LIST_BASE_GET_CLASS (widget)->create_list_widget (GTK_LIST_BASE (widget));
 }

+static void
+gtk_list_base_prepare_section_func (GtkWidget   *widget,
+                                    GtkListTile *tile,
+                                    guint        pos)
+{
+  GTK_LIST_BASE_GET_CLASS (widget)->prepare_section (GTK_LIST_BASE (widget), tile, pos);
+}
+
+static GtkListHeaderBase *
+gtk_list_base_create_header_widget_func (GtkWidget *widget)
+{
+  return GTK_LIST_BASE_GET_CLASS (widget)->create_header_widget (GTK_LIST_BASE (widget));
+}
+
 static void
 gtk_list_base_init_real (GtkListBase      *self,
                         GtkListBaseClass *g_class)
@@ -1968,7 +1982,9 @@ gtk_list_base_init_real (GtkListBase      *self,

  priv->item_manager = gtk_list_item_manager_new (GTK_WIDGET (self),
                                                  gtk_list_base_split_func,
-                                                  gtk_list_base_create_widget_func);
+                                                  gtk_list_base_create_list_widget_func,
+                                                  gtk_list_base_prepare_section_func,
+                                                  gtk_list_base_create_header_widget_func);
  priv->anchor = gtk_list_item_tracker_new (priv->item_manager);
  priv->anchor_side_along = GTK_PACK_START;
  priv->anchor_side_across = GTK_PACK_START;
--- a/gtk/gtklistbaseprivate.h
+++ b/gtk/gtklistbaseprivate.h
@@ -37,6 +37,10 @@ struct _GtkListBaseClass
                                                                 GtkListTile            *tile,
                                                                 guint                   n_items);
  GtkListItemBase *    (* create_list_widget)                   (GtkListBase            *self);
+  void                 (* prepare_section)                      (GtkListBase            *self,
+                                                                 GtkListTile            *tile,
+                                                                 guint                   position);
+  GtkListHeaderBase *  (* create_header_widget)                 (GtkListBase            *self);

  gboolean             (* get_allocation)                       (GtkListBase            *self,
                                                                 guint                   pos,
--- a/gtk/gtklistheader.c
+++ b/gtk/gtklistheader.c
@@ -0,0 +1,381 @@
+/*
+ * Copyright © 2023 Benjamin Otte
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Benjamin Otte <otte@gnome.org>
+ */
+
+#include "config.h"
+
+#include "gtklistheaderprivate.h"
+
+/**
+ * GtkListHeader:
+ *
+ * `GtkListHeader` is used by list widgets to represent the headers they
+ * display.
+ *
+ * The `GtkListHeader`s are managed just like [class@gtk.ListItem]s via
+ * their factory, but provide a different set of properties suitable for
+ * managing the header instead of individual items.
+ *
+ * Since: 4.12
+ */
+
+enum
+{
+  PROP_0,
+  PROP_CHILD,
+  PROP_END,
+  PROP_ITEM,
+  PROP_N_ITEMS,
+  PROP_START,
+
+  N_PROPS
+};
+
+G_DEFINE_TYPE (GtkListHeader, gtk_list_header, G_TYPE_OBJECT)
+
+static GParamSpec *properties[N_PROPS] = { NULL, };
+
+static void
+gtk_list_header_dispose (GObject *object)
+{
+  GtkListHeader *self = GTK_LIST_HEADER (object);
+
+  g_assert (self->owner == NULL); /* would hold a reference */
+  g_clear_object (&self->child);
+
+  G_OBJECT_CLASS (gtk_list_header_parent_class)->dispose (object);
+}
+
+static void
+gtk_list_header_get_property (GObject    *object,
+                              guint       property_id,
+                              GValue     *value,
+                              GParamSpec *pspec)
+{
+  GtkListHeader *self = GTK_LIST_HEADER (object);
+
+  switch (property_id)
+    {
+    case PROP_CHILD:
+      g_value_set_object (value, self->child);
+      break;
+
+    case PROP_END:
+      if (self->owner)
+        g_value_set_uint (value, gtk_list_header_base_get_end (GTK_LIST_HEADER_BASE (self->owner)));
+      else
+        g_value_set_uint (value, GTK_INVALID_LIST_POSITION);
+      break;
+
+    case PROP_ITEM:
+      if (self->owner)
+        g_value_set_object (value, gtk_list_header_base_get_item (GTK_LIST_HEADER_BASE (self->owner)));
+      break;
+
+    case PROP_N_ITEMS:
+      g_value_set_uint (value, gtk_list_header_get_n_items (self));
+      break;
+
+    case PROP_START:
+      if (self->owner)
+        g_value_set_uint (value, gtk_list_header_base_get_start (GTK_LIST_HEADER_BASE (self->owner)));
+      else
+        g_value_set_uint (value, GTK_INVALID_LIST_POSITION);
+      break;
+
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
+      break;
+    }
+}
+
+static void
+gtk_list_header_set_property (GObject      *object,
+                              guint         property_id,
+                              const GValue *value,
+                              GParamSpec   *pspec)
+{
+  GtkListHeader *self = GTK_LIST_HEADER (object);
+
+  switch (property_id)
+    {
+    case PROP_CHILD:
+      gtk_list_header_set_child (self, g_value_get_object (value));
+      break;
+
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
+      break;
+    }
+}
+
+static void
+gtk_list_header_class_init (GtkListHeaderClass *klass)
+{
+  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
+
+  gobject_class->dispose = gtk_list_header_dispose;
+  gobject_class->get_property = gtk_list_header_get_property;
+  gobject_class->set_property = gtk_list_header_set_property;
+
+  /**
+   * GtkListHeader:child: (attributes org.gtk.Property.get=gtk_list_header_get_child org.gtk.Property.set=gtk_list_header_set_child)
+   *
+   * Widget used for display.
+   *
+   * Since: 4.12
+   */
+  properties[PROP_CHILD] =
+    g_param_spec_object ("child", NULL, NULL,
+                         GTK_TYPE_WIDGET,
+                         G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
+  /**
+   * GtkListHeader:end: (attributes org.gtk.Property.get=gtk_list_header_get_end)
+   *
+   * The first position no longer part of this section.
+   *
+   * Since: 4.12
+   */
+  properties[PROP_END] =
+    g_param_spec_uint ("end", NULL, NULL,
+                       0, G_MAXUINT, GTK_INVALID_LIST_POSITION,
+                       G_PARAM_READABLE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
+  /**
+   * GtkListHeader:item: (attributes org.gtk.Property.get=gtk_list_header_get_item)
+   *
+   * The item at the start of the section.
+   *
+   * Since: 4.12
+   */
+  properties[PROP_ITEM] =
+    g_param_spec_object ("item", NULL, NULL,
+                         G_TYPE_OBJECT,
+                         G_PARAM_READABLE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
+  /**
+   * GtkListHeader:n-items: (attributes org.gtk.Property.get=gtk_list_header_get_n_items)
+   *
+   * Number of items in this section.
+   *
+   * Since: 4.12
+   */
+  properties[PROP_N_ITEMS] =
+    g_param_spec_uint ("n-items", NULL, NULL,
+                       0, G_MAXUINT, 0,
+                       G_PARAM_READABLE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
+  /**
+   * GtkListHeader:start: (attributes org.gtk.Property.get=gtk_list_header_get_start)
+   *
+   * First position of items in this section.
+   *
+   * Since: 4.12
+   */
+  properties[PROP_START] =
+    g_param_spec_uint ("start", NULL, NULL,
+                       0, G_MAXUINT, GTK_INVALID_LIST_POSITION,
+                       G_PARAM_READABLE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
+  g_object_class_install_properties (gobject_class, N_PROPS, properties);
+}
+
+static void
+gtk_list_header_init (GtkListHeader *self)
+{
+}
+
+GtkListHeader *
+gtk_list_header_new (void)
+{
+  return g_object_new (GTK_TYPE_LIST_HEADER, NULL);
+}
+
+void
+gtk_list_header_do_notify (GtkListHeader *list_header,
+                           gboolean notify_item,
+                           gboolean notify_start,
+                           gboolean notify_end,
+                           gboolean notify_n_items)
+{
+  GObject *object = G_OBJECT (list_header);
+
+  if (notify_item)
+    g_object_notify_by_pspec (object, properties[PROP_ITEM]);
+  if (notify_start)
+    g_object_notify_by_pspec (object, properties[PROP_START]);
+  if (notify_end)
+    g_object_notify_by_pspec (object, properties[PROP_END]);
+  if (notify_n_items)
+    g_object_notify_by_pspec (object, properties[PROP_N_ITEMS]);
+}
+
+/**
+ * gtk_list_header_get_item: (attributes org.gtk.Method.get_property=item)
+ * @self: a `GtkListHeader`
+ *
+ * Gets the model item at the start of the section.
+ * This is the item that occupies the list model at position
+ * [property@Gtk.ListHeader:start].
+ *
+ * If @self is unbound, this function returns %NULL.
+ *
+ * Returns: (nullable) (transfer none) (type GObject): The item displayed
+ *
+ * Since: 4.12
+ **/
+gpointer
+gtk_list_header_get_item (GtkListHeader *self)
+{
+  g_return_val_if_fail (GTK_IS_LIST_HEADER (self), NULL);
+
+  if (self->owner)
+    return gtk_list_header_base_get_item (GTK_LIST_HEADER_BASE (self->owner));
+  else
+    return NULL;
+}
+
+/**
+ * gtk_list_header_get_child: (attributes org.gtk.Method.get_property=child)
+ * @self: a `GtkListHeader`
+ *
+ * Gets the child previously set via gtk_list_header_set_child() or
+ * %NULL if none was set.
+ *
+ * Returns: (transfer none) (nullable): The child
+ *
+ * Since: 4.12
+ */
+GtkWidget *
+gtk_list_header_get_child (GtkListHeader *self)
+{
+  g_return_val_if_fail (GTK_IS_LIST_HEADER (self), NULL);
+
+  return self->child;
+}
+
+/**
+ * gtk_list_header_set_child: (attributes org.gtk.Method.set_property=child)
+ * @self: a `GtkListHeader`
+ * @child: (nullable): The list item's child or %NULL to unset
+ *
+ * Sets the child to be used for this listitem.
+ *
+ * This function is typically called by applications when
+ * setting up a header so that the widget can be reused when
+ * binding it multiple times.
+ *
+ * Since: 4.12
+ */
+void
+gtk_list_header_set_child (GtkListHeader *self,
+                           GtkWidget   *child)
+{
+  g_return_if_fail (GTK_IS_LIST_HEADER (self));
+  g_return_if_fail (child == NULL || gtk_widget_get_parent (child) == NULL);
+
+  if (self->child == child)
+    return;
+
+  g_clear_object (&self->child);
+
+  if (child)
+    {
+      g_object_ref_sink (child);
+      self->child = child;
+    }
+
+  if (self->owner)
+    gtk_list_header_widget_set_child (self->owner, child);
+
+  g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_CHILD]);
+}
+
+/**
+ * gtk_list_header_get_start: (attributes org.gtk.Method.get_property=start)
+ * @self: a `GtkListHeader`
+ *
+ * Gets the start position in the model of the section that @self is
+ * currently the header for.
+ *
+ * If @self is unbound, %GTK_INVALID_LIST_POSITION is returned.
+ *
+ * Returns: The start position of the section
+ *
+ * Since: 4.12
+ */
+guint
+gtk_list_header_get_start (GtkListHeader *self)
+{
+  g_return_val_if_fail (GTK_IS_LIST_HEADER (self), GTK_INVALID_LIST_POSITION);
+
+  if (self->owner)
+    return gtk_list_header_base_get_start (GTK_LIST_HEADER_BASE (self->owner));
+  else
+    return GTK_INVALID_LIST_POSITION;
+}
+
+/**
+ * gtk_list_header_get_end: (attributes org.gtk.Method.get_property=end)
+ * @self: a `GtkListHeader`
+ *
+ * Gets the end position in the model of the section that @self is
+ * currently the header for.
+ *
+ * If @self is unbound, %GTK_INVALID_LIST_POSITION is returned.
+ *
+ * Returns: The end position of the section
+ *
+ * Since: 4.12
+ */
+guint
+gtk_list_header_get_end (GtkListHeader *self)
+{
+  g_return_val_if_fail (GTK_IS_LIST_HEADER (self), GTK_INVALID_LIST_POSITION);
+
+  if (self->owner)
+    return gtk_list_header_base_get_end (GTK_LIST_HEADER_BASE (self->owner));
+  else
+    return GTK_INVALID_LIST_POSITION;
+}
+
+/**
+ * gtk_list_header_get_n_items: (attributes org.gtk.Method.get_property=n-items)
+ * @self: a `GtkListHeader`
+ *
+ * Gets the the number of items in the section.
+ *
+ * If @self is unbound, 0 is returned.
+ *
+ * Returns: The number of items in the section
+ *
+ * Since: 4.12
+ */
+guint
+gtk_list_header_get_n_items (GtkListHeader *self)
+{
+  g_return_val_if_fail (GTK_IS_LIST_HEADER (self), GTK_INVALID_LIST_POSITION);
+
+  if (self->owner)
+    return gtk_list_header_base_get_end (GTK_LIST_HEADER_BASE (self->owner)) -
+           gtk_list_header_base_get_start (GTK_LIST_HEADER_BASE (self->owner));
+  else
+    return 0;
+}
+
--- a/gtk/gtklistheader.h
+++ b/gtk/gtklistheader.h
@@ -0,0 +1,50 @@
+/*
+ * Copyright © 2023 Benjamin Otte
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Benjamin Otte <otte@gnome.org>
+ */
+
+#pragma once
+
+#if !defined (__GTK_H_INSIDE__) && !defined (GTK_COMPILATION)
+#error "Only <gtk/gtk.h> can be included directly."
+#endif
+
+#include <gtk/gtktypes.h>
+
+G_BEGIN_DECLS
+
+#define GTK_TYPE_LIST_HEADER (gtk_list_header_get_type ())
+GDK_AVAILABLE_IN_4_12
+GDK_DECLARE_INTERNAL_TYPE (GtkListHeader, gtk_list_header, GTK, LIST_HEADER, GObject)
+
+GDK_AVAILABLE_IN_4_12
+gpointer        gtk_list_header_get_item                        (GtkListHeader          *self);
+GDK_AVAILABLE_IN_4_12
+guint           gtk_list_header_get_start                       (GtkListHeader          *self) G_GNUC_PURE;
+GDK_AVAILABLE_IN_4_12
+guint           gtk_list_header_get_end                         (GtkListHeader          *self) G_GNUC_PURE;
+GDK_AVAILABLE_IN_4_12
+guint           gtk_list_header_get_n_items                     (GtkListHeader          *self) G_GNUC_PURE;
+
+GDK_AVAILABLE_IN_4_12
+void            gtk_list_header_set_child                       (GtkListHeader          *self,
+                                                                 GtkWidget              *child);
+GDK_AVAILABLE_IN_4_12
+GtkWidget *     gtk_list_header_get_child                       (GtkListHeader          *self);
+
+G_END_DECLS
+
--- a/gtk/gtklistheaderbase.c
+++ b/gtk/gtklistheaderbase.c
@@ -0,0 +1,112 @@
+/*
+ * Copyright © 2023 Benjamin Otte
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Benjamin Otte <otte@gnome.org>
+ */
+
+#include "config.h"
+
+#include "gtklistheaderbaseprivate.h"
+
+typedef struct _GtkListHeaderBasePrivate GtkListHeaderBasePrivate;
+struct _GtkListHeaderBasePrivate
+{
+  GObject *item;
+  guint start;
+  guint end;
+};
+
+G_DEFINE_TYPE_WITH_PRIVATE (GtkListHeaderBase, gtk_list_header_base, GTK_TYPE_WIDGET)
+
+static void
+gtk_list_header_base_default_update (GtkListHeaderBase *self,
+                                     gpointer           item,
+                                     guint              start,
+                                     guint              end)
+{
+  GtkListHeaderBasePrivate *priv = gtk_list_header_base_get_instance_private (self);
+
+  g_set_object (&priv->item, item);
+  priv->start = start;
+  priv->end = end;
+}
+
+static void
+gtk_list_header_base_dispose (GObject *object)
+{
+  GtkListHeaderBase *self = GTK_LIST_HEADER_BASE (object);
+  GtkListHeaderBasePrivate *priv = gtk_list_header_base_get_instance_private (self);
+
+  g_clear_object (&priv->item);
+
+  G_OBJECT_CLASS (gtk_list_header_base_parent_class)->dispose (object);
+}
+
+static void
+gtk_list_header_base_class_init (GtkListHeaderBaseClass *klass)
+{
+  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
+
+  klass->update = gtk_list_header_base_default_update;
+
+  gobject_class->dispose = gtk_list_header_base_dispose;
+}
+
+static void
+gtk_list_header_base_init (GtkListHeaderBase *self)
+{
+}
+
+void
+gtk_list_header_base_update (GtkListHeaderBase *self,
+                             gpointer           item,
+                             guint              start,
+                             guint              end)
+{
+  GtkListHeaderBasePrivate *priv = gtk_list_header_base_get_instance_private (self);
+
+  if (priv->item == item &&
+      priv->start == start && 
+      priv->end == end)
+    return;
+
+  GTK_LIST_HEADER_BASE_GET_CLASS (self)->update (self, item, start, end);
+}
+
+guint
+gtk_list_header_base_get_start (GtkListHeaderBase *self)
+{
+  GtkListHeaderBasePrivate *priv = gtk_list_header_base_get_instance_private (self);
+
+  return priv->start;
+}
+
+guint
+gtk_list_header_base_get_end (GtkListHeaderBase *self)
+{
+  GtkListHeaderBasePrivate *priv = gtk_list_header_base_get_instance_private (self);
+
+  return priv->end;
+}
+
+gpointer
+gtk_list_header_base_get_item (GtkListHeaderBase *self)
+{
+  GtkListHeaderBasePrivate *priv = gtk_list_header_base_get_instance_private (self);
+
+  return priv->item;
+}
+
--- a/gtk/gtklistheaderbaseprivate.h
+++ b/gtk/gtklistheaderbaseprivate.h
@@ -0,0 +1,63 @@
+/*
+ * Copyright © 2023 Benjamin Otte
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Benjamin Otte <otte@gnome.org>
+ */
+
+#pragma once
+
+#include "gtkwidget.h"
+
+G_BEGIN_DECLS
+
+#define GTK_TYPE_LIST_HEADER_BASE         (gtk_list_header_base_get_type ())
+#define GTK_LIST_HEADER_BASE(o)           (G_TYPE_CHECK_INSTANCE_CAST ((o), GTK_TYPE_LIST_HEADER_BASE, GtkListHeaderBase))
+#define GTK_LIST_HEADER_BASE_CLASS(k)     (G_TYPE_CHECK_CLASS_CAST ((k), GTK_TYPE_LIST_HEADER_BASE, GtkListHeaderBaseClass))
+#define GTK_IS_LIST_HEADER_BASE(o)        (G_TYPE_CHECK_INSTANCE_TYPE ((o), GTK_TYPE_LIST_HEADER_BASE))
+#define GTK_IS_LIST_HEADER_BASE_CLASS(k)  (G_TYPE_CHECK_CLASS_TYPE ((k), GTK_TYPE_LIST_HEADER_BASE))
+#define GTK_LIST_HEADER_BASE_GET_CLASS(o) (G_TYPE_INSTANCE_GET_CLASS ((o), GTK_TYPE_LIST_HEADER_BASE, GtkListHeaderBaseClass))
+
+typedef struct _GtkListHeaderBase GtkListHeaderBase;
+typedef struct _GtkListHeaderBaseClass GtkListHeaderBaseClass;
+
+struct _GtkListHeaderBase
+{
+  GtkWidget parent_instance;
+};
+
+struct _GtkListHeaderBaseClass
+{
+  GtkWidgetClass parent_class;
+
+  void                  (* update)                              (GtkListHeaderBase      *self,
+                                                                 gpointer                item,
+                                                                 guint                   start,
+                                                                 guint                   end);
+};
+
+GType                   gtk_list_header_base_get_type           (void) G_GNUC_CONST;
+
+void                    gtk_list_header_base_update             (GtkListHeaderBase      *self,
+                                                                 gpointer                item,
+                                                                 guint                   start,
+                                                                 guint                   end);
+
+guint                   gtk_list_header_base_get_start          (GtkListHeaderBase      *self);
+guint                   gtk_list_header_base_get_end            (GtkListHeaderBase      *self);
+gpointer                gtk_list_header_base_get_item           (GtkListHeaderBase      *self);
+
+G_END_DECLS
+
--- a/gtk/gtklistheaderprivate.h
+++ b/gtk/gtklistheaderprivate.h
@@ -0,0 +1,52 @@
+/*
+ * Copyright © 2023 Benjamin Otte
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Benjamin Otte <otte@gnome.org>
+ */
+
+#pragma once
+
+#include "gtklistheader.h"
+
+#include "gtklistheaderwidgetprivate.h"
+
+G_BEGIN_DECLS
+
+struct _GtkListHeader
+{
+  GObject parent_instance;
+
+  GtkListHeaderWidget *owner; /* has a reference */
+
+  GtkWidget *child;
+};
+
+struct _GtkListHeaderClass
+{
+  GObjectClass parent_class;
+};
+
+GtkListHeader * gtk_list_header_new                             (void);
+
+void            gtk_list_header_do_notify                       (GtkListHeader          *list_header,
+                                                                 gboolean                notify_item,
+                                                                 gboolean                notify_start,
+                                                                 gboolean                notify_end,
+                                                                 gboolean                notify_n_items);
+
+
+G_END_DECLS
+
--- a/gtk/gtklistheaderwidget.c
+++ b/gtk/gtklistheaderwidget.c
@@ -0,0 +1,295 @@
+/*
+ * Copyright © 2023 Benjamin Otte
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Benjamin Otte <otte@gnome.org>
+ */
+
+#include "config.h"
+
+#include "gtklistheaderwidgetprivate.h"
+
+#include "gtkbinlayout.h"
+#include "gtklistheaderprivate.h"
+#include "gtklistitemfactoryprivate.h"
+#include "gtklistbaseprivate.h"
+#include "gtkwidget.h"
+
+typedef struct _GtkListHeaderWidgetPrivate GtkListHeaderWidgetPrivate;
+struct _GtkListHeaderWidgetPrivate
+{
+  GtkListItemFactory *factory;
+
+  GtkListHeader *header;
+};
+
+enum {
+  PROP_0,
+  PROP_FACTORY,
+
+  N_PROPS
+};
+
+G_DEFINE_TYPE_WITH_PRIVATE (GtkListHeaderWidget, gtk_list_header_widget, GTK_TYPE_LIST_HEADER_BASE)
+
+static GParamSpec *properties[N_PROPS] = { NULL, };
+
+static void
+gtk_list_header_widget_setup_func (gpointer object,
+                                   gpointer data)
+{
+  GtkListHeaderWidget *self = GTK_LIST_HEADER_WIDGET (data);
+  GtkListHeaderWidgetPrivate *priv = gtk_list_header_widget_get_instance_private (self);
+  GtkListHeader *header = object;
+
+  priv->header = header;
+  header->owner = self;
+
+  gtk_list_header_widget_set_child (self, header->child);
+
+  gtk_list_header_do_notify (header,
+                             gtk_list_header_base_get_item (GTK_LIST_HEADER_BASE (self)) != NULL,
+                             gtk_list_header_base_get_start (GTK_LIST_HEADER_BASE (self)) != GTK_INVALID_LIST_POSITION,
+                             gtk_list_header_base_get_end (GTK_LIST_HEADER_BASE (self)) != GTK_INVALID_LIST_POSITION,
+                             gtk_list_header_base_get_start (GTK_LIST_HEADER_BASE (self)) != gtk_list_header_base_get_end (GTK_LIST_HEADER_BASE (self)));
+}
+
+static void
+gtk_list_header_widget_setup_factory (GtkListHeaderWidget *self)
+{
+  GtkListHeaderWidgetPrivate *priv = gtk_list_header_widget_get_instance_private (self);
+  GtkListHeader *header;
+
+  header = gtk_list_header_new ();
+
+  gtk_list_item_factory_setup (priv->factory,
+                               G_OBJECT (header),
+                               gtk_list_header_base_get_item (GTK_LIST_HEADER_BASE (self)) != NULL,
+                               gtk_list_header_widget_setup_func,
+                               self);
+
+  g_assert (priv->header == header);
+}
+
+static void
+gtk_list_header_widget_teardown_func (gpointer object,
+                                      gpointer data)
+{
+  GtkListHeaderWidget *self = GTK_LIST_HEADER_WIDGET (data);
+  GtkListHeaderWidgetPrivate *priv = gtk_list_header_widget_get_instance_private (self);
+  GtkListHeader *header = object;
+
+  header->owner = NULL;
+  priv->header = NULL;
+
+  gtk_list_header_widget_set_child (self, NULL);
+
+  gtk_list_header_do_notify (header,
+                             gtk_list_header_base_get_item (GTK_LIST_HEADER_BASE (self)) != NULL,
+                             gtk_list_header_base_get_start (GTK_LIST_HEADER_BASE (self)) != GTK_INVALID_LIST_POSITION,
+                             gtk_list_header_base_get_end (GTK_LIST_HEADER_BASE (self)) != GTK_INVALID_LIST_POSITION,
+                             gtk_list_header_base_get_start (GTK_LIST_HEADER_BASE (self)) != gtk_list_header_base_get_end (GTK_LIST_HEADER_BASE (self)));
+}
+
+static void
+gtk_list_header_widget_teardown_factory (GtkListHeaderWidget *self)
+{
+  GtkListHeaderWidgetPrivate *priv = gtk_list_header_widget_get_instance_private (self);
+  gpointer header = priv->header;
+
+  gtk_list_item_factory_teardown (priv->factory,
+                                  header,
+                                  gtk_list_header_base_get_item (GTK_LIST_HEADER_BASE (self)) != NULL,
+                                  gtk_list_header_widget_teardown_func,
+                                  self);
+
+  g_assert (priv->header == NULL);
+  g_object_unref (header);
+}
+
+typedef struct {
+  GtkListHeaderWidget *widget;
+  gpointer item;
+  guint start;
+  guint end;
+} GtkListHeaderWidgetUpdate;
+
+static void
+gtk_list_header_widget_update_func (gpointer object,
+                                    gpointer data)
+{
+  GtkListHeaderWidgetUpdate *update = data;
+  GtkListHeaderWidget *self = update->widget;
+  GtkListHeaderBase *base = GTK_LIST_HEADER_BASE (self);
+  /* Track notify manually instead of freeze/thaw_notify for performance reasons. */
+  gboolean notify_item, notify_start, notify_end, notify_n_items;
+
+  /* FIXME: It's kinda evil to notify external objects from here... */
+  notify_item = gtk_list_header_base_get_item (base) != update->item;
+  notify_start = gtk_list_header_base_get_start (base) != update->start;
+  notify_end = gtk_list_header_base_get_end (base) != update->end;
+  notify_n_items = gtk_list_header_base_get_end (base) - gtk_list_header_base_get_start (base) != update->end - update->start;
+
+  GTK_LIST_HEADER_BASE_CLASS (gtk_list_header_widget_parent_class)->update (base,
+                                                                            update->item,
+                                                                            update->start,
+                                                                            update->end);
+
+  if (object)
+    gtk_list_header_do_notify (object, notify_item, notify_start, notify_end, notify_n_items);
+}
+
+static void
+gtk_list_header_widget_update (GtkListHeaderBase *base,
+                               gpointer           item,
+                               guint              start,
+                               guint              end)
+{
+  GtkListHeaderWidget *self = GTK_LIST_HEADER_WIDGET (base);
+  GtkListHeaderWidgetPrivate *priv = gtk_list_header_widget_get_instance_private (self);
+  GtkListHeaderWidgetUpdate update = { self, item, start, end };
+
+  if (priv->header)
+    {
+      gtk_list_item_factory_update (priv->factory,
+                                    G_OBJECT (priv->header),
+                                    gtk_list_header_base_get_item (GTK_LIST_HEADER_BASE (self)) != NULL,
+                                    item != NULL,
+                                    gtk_list_header_widget_update_func,
+                                    &update);
+    }
+  else
+    {
+      gtk_list_header_widget_update_func (NULL, &update);
+    }
+}
+
+static void
+gtk_list_header_widget_set_property (GObject      *object,
+                                     guint         property_id,
+                                     const GValue *value,
+                                     GParamSpec   *pspec)
+{
+  GtkListHeaderWidget *self = GTK_LIST_HEADER_WIDGET (object);
+
+  switch (property_id)
+    {
+    case PROP_FACTORY:
+      gtk_list_header_widget_set_factory (self, g_value_get_object (value));
+      break;
+
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
+      break;
+    }
+}
+
+static void
+gtk_list_header_widget_clear_factory (GtkListHeaderWidget *self)
+{
+  GtkListHeaderWidgetPrivate *priv = gtk_list_header_widget_get_instance_private (self);
+
+  if (priv->factory == NULL)
+    return;
+
+  if (priv->header)
+    gtk_list_header_widget_teardown_factory (self);
+
+  g_clear_object (&priv->factory);
+}
+
+static void
+gtk_list_header_widget_dispose (GObject *object)
+{
+  GtkListHeaderWidget *self = GTK_LIST_HEADER_WIDGET (object);
+
+  gtk_list_header_widget_clear_factory (self);
+
+  G_OBJECT_CLASS (gtk_list_header_widget_parent_class)->dispose (object);
+}
+
+static void
+gtk_list_header_widget_class_init (GtkListHeaderWidgetClass *klass)
+{
+  GtkListHeaderBaseClass *base_class = GTK_LIST_HEADER_BASE_CLASS (klass);
+  GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (klass);
+  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
+
+  base_class->update = gtk_list_header_widget_update;
+
+  gobject_class->set_property = gtk_list_header_widget_set_property;
+  gobject_class->dispose = gtk_list_header_widget_dispose;
+
+  properties[PROP_FACTORY] =
+    g_param_spec_object ("factory", NULL, NULL,
+                         GTK_TYPE_LIST_ITEM_FACTORY,
+                         G_PARAM_WRITABLE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
+  g_object_class_install_properties (gobject_class, N_PROPS, properties);
+
+  gtk_widget_class_set_css_name (widget_class, I_("header"));
+  gtk_widget_class_set_accessible_role (widget_class, GTK_ACCESSIBLE_ROLE_ROW_HEADER);
+  gtk_widget_class_set_layout_manager_type (widget_class, GTK_TYPE_BIN_LAYOUT);
+}
+
+static void
+gtk_list_header_widget_init (GtkListHeaderWidget *self)
+{
+}
+
+void
+gtk_list_header_widget_set_factory (GtkListHeaderWidget *self,
+                                    GtkListItemFactory  *factory)
+{
+  GtkListHeaderWidgetPrivate *priv = gtk_list_header_widget_get_instance_private (self);
+
+  if (priv->factory == factory)
+    return;
+
+  gtk_list_header_widget_clear_factory (self);
+
+  if (factory)
+    {
+      priv->factory = g_object_ref (factory);
+
+      gtk_list_header_widget_setup_factory (self);
+    }
+
+  g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_FACTORY]);
+}
+
+GtkWidget *
+gtk_list_header_widget_new (GtkListItemFactory *factory)
+{
+  return g_object_new (GTK_TYPE_LIST_HEADER_WIDGET,
+                       "factory", factory,
+                       NULL);
+}
+
+void
+gtk_list_header_widget_set_child (GtkListHeaderWidget *self,
+                                  GtkWidget           *child)
+{
+  GtkWidget *cur_child = gtk_widget_get_first_child (GTK_WIDGET (self));
+
+  if (cur_child == child)
+    return;
+
+  g_clear_pointer (&cur_child, gtk_widget_unparent);
+
+  if (child)
+    gtk_widget_set_parent (child, GTK_WIDGET (self));
+}
+
--- a/gtk/gtklistheaderwidgetprivate.h
+++ b/gtk/gtklistheaderwidgetprivate.h
@@ -0,0 +1,61 @@
+/*
+ * Copyright © 2023 Benjamin Otte
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Benjamin Otte <otte@gnome.org>
+ */
+
+#pragma once
+
+#include "gtklistheaderbaseprivate.h"
+
+#include "gtklistitemfactory.h"
+
+G_BEGIN_DECLS
+
+#define GTK_TYPE_LIST_HEADER_WIDGET         (gtk_list_header_widget_get_type ())
+#define GTK_LIST_HEADER_WIDGET(o)           (G_TYPE_CHECK_INSTANCE_CAST ((o), GTK_TYPE_LIST_HEADER_WIDGET, GtkListHeaderWidget))
+#define GTK_LIST_HEADER_WIDGET_CLASS(k)     (G_TYPE_CHECK_CLASS_CAST ((k), GTK_TYPE_LIST_HEADER_WIDGET, GtkListHeaderWidgetClass))
+#define GTK_IS_LIST_HEADER_WIDGET(o)        (G_TYPE_CHECK_INSTANCE_TYPE ((o), GTK_TYPE_LIST_HEADER_WIDGET))
+#define GTK_IS_LIST_HEADER_WIDGET_CLASS(k)  (G_TYPE_CHECK_CLASS_TYPE ((k), GTK_TYPE_LIST_HEADER_WIDGET))
+#define GTK_LIST_HEADER_WIDGET_GET_CLASS(o) (G_TYPE_INSTANCE_GET_CLASS ((o), GTK_TYPE_LIST_HEADER_WIDGET, GtkListHeaderWidgetClass))
+
+typedef struct _GtkListHeaderWidget GtkListHeaderWidget;
+typedef struct _GtkListHeaderWidgetClass GtkListHeaderWidgetClass;
+
+struct _GtkListHeaderWidget
+{
+  GtkListHeaderBase parent_instance;
+};
+
+struct _GtkListHeaderWidgetClass
+{
+  GtkListHeaderBaseClass parent_class;
+};
+
+GType                   gtk_list_header_widget_get_type         (void) G_GNUC_CONST;
+
+GtkWidget *             gtk_list_header_widget_new              (GtkListItemFactory     *factory);
+
+void                    gtk_list_header_widget_set_factory      (GtkListHeaderWidget    *self,
+                                                                 GtkListItemFactory     *factory);
+GtkListItemFactory *    gtk_list_header_widget_get_factory      (GtkListHeaderWidget    *self);
+
+void                    gtk_list_header_widget_set_child        (GtkListHeaderWidget    *self,
+                                                                 GtkWidget              *child);
+
+
+G_END_DECLS
+
--- a/gtk/gtklistitembase.c
+++ b/gtk/gtklistitembase.c
@@ -81,6 +81,11 @@ gtk_list_item_base_update (GtkListItemBase *self,
  GtkListItemBasePrivate *priv = gtk_list_item_base_get_instance_private (self);
  gboolean was_selected;

+  if (priv->position == position &&
+      priv->item == item &&
+      priv->selected == selected)
+    return;
+
  was_selected = priv->selected;

  GTK_LIST_ITEM_BASE_GET_CLASS (self)->update (self, position, item, selected);
--- a/gtk/gtklistitemmanager.c
+++ b/gtk/gtklistitemmanager.c
--- a/gtk/gtklistitemmanagerprivate.h
+++ b/gtk/gtklistitemmanagerprivate.h
@@ -24,6 +24,7 @@
 #include "gtk/gtkenums.h"

 #include "gtk/gtklistitembaseprivate.h"
+#include "gtk/gtklistheaderbaseprivate.h"
 #include "gtk/gtklistitemfactory.h"
 #include "gtk/gtkrbtreeprivate.h"
 #include "gtk/gtkselectionmodel.h"
@@ -43,8 +44,20 @@ typedef struct _GtkListTile GtkListTile;
 typedef struct _GtkListTileAugment GtkListTileAugment;
 typedef struct _GtkListItemTracker GtkListItemTracker;

+typedef enum
+{
+  GTK_LIST_TILE_ITEM,
+  GTK_LIST_TILE_HEADER,
+  GTK_LIST_TILE_FOOTER,
+  GTK_LIST_TILE_UNMATCHED_HEADER,
+  GTK_LIST_TILE_UNMATCHED_FOOTER,
+  GTK_LIST_TILE_FILLER,
+  GTK_LIST_TILE_REMOVED,
+} GtkListTileType;
+
 struct _GtkListTile
 {
+  GtkListTileType type;
  GtkWidget *widget;
  guint n_items;
  /* area occupied by tile. May be empty if tile has no allcoation */
@@ -54,6 +67,10 @@ struct _GtkListTile
 struct _GtkListTileAugment
 {
  guint n_items;
+
+  guint has_header :1;
+  guint has_footer :1;
+
  /* union of all areas of tile and children */
  cairo_rectangle_int_t area;
 };
@@ -63,7 +80,9 @@ GType                   gtk_list_item_manager_get_type          (void) G_GNUC_CO

 GtkListItemManager *    gtk_list_item_manager_new               (GtkWidget              *widget,
                                                                 GtkListTile *           (* split_func) (GtkWidget *, GtkListTile *, guint),
-                                                                 GtkListItemBase *       (* create_widget) (GtkWidget *));
+                                                                 GtkListItemBase *       (* create_widget) (GtkWidget *),
+                                                                 void                    (* prepare_section) (GtkWidget *, GtkListTile *, guint),
+                                                                 GtkListHeaderBase *     (* create_header_widget) (GtkWidget *));

 void                    gtk_list_item_manager_get_tile_bounds   (GtkListItemManager     *self,
                                                                 GdkRectangle           *out_bounds);
@@ -97,12 +116,17 @@ void                    gtk_list_tile_set_area_size             (GtkListItemMana
 GtkListTile *           gtk_list_tile_split                     (GtkListItemManager     *self,
                                                                 GtkListTile            *tile,
                                                                 guint                   n_items);
+GtkListTile *           gtk_list_tile_append_filler             (GtkListItemManager     *self,
+                                                                 GtkListTile            *previous);
 GtkListTile *           gtk_list_tile_gc                        (GtkListItemManager     *self,
                                                                 GtkListTile            *tile);

 void                    gtk_list_item_manager_set_model         (GtkListItemManager     *self,
                                                                 GtkSelectionModel      *model);
 GtkSelectionModel *     gtk_list_item_manager_get_model         (GtkListItemManager     *self);
+void                    gtk_list_item_manager_set_has_sections  (GtkListItemManager     *self,
+                                                                 gboolean                has_sections);
+gboolean                gtk_list_item_manager_get_has_sections  (GtkListItemManager     *self);

 GtkListItemTracker *    gtk_list_item_tracker_new               (GtkListItemManager     *self);
 void                    gtk_list_item_tracker_free              (GtkListItemManager     *self,
--- a/gtk/gtklistview.c
+++ b/gtk/gtklistview.c
@@ -23,6 +23,7 @@

 #include "gtkbitset.h"
 #include "gtklistbaseprivate.h"
+#include "gtklistheaderwidgetprivate.h"
 #include "gtklistitemmanagerprivate.h"
 #include "gtklistitemwidgetprivate.h"
 #include "gtkmultiselection.h"
@@ -145,6 +146,7 @@ enum
  PROP_0,
  PROP_ENABLE_RUBBERBAND,
  PROP_FACTORY,
+  PROP_HEADER_FACTORY,
  PROP_MODEL,
  PROP_SHOW_SEPARATORS,
  PROP_SINGLE_CLICK_ACTIVATE,
@@ -163,29 +165,6 @@ G_DEFINE_TYPE (GtkListView, gtk_list_view, GTK_TYPE_LIST_BASE)
 static GParamSpec *properties[N_PROPS] = { NULL, };
 static guint signals[LAST_SIGNAL] = { 0 };

-static void G_GNUC_UNUSED
-dump (GtkListView *self)
-{
-  GtkListTile *tile;
-  guint n_widgets, n_list_rows;
-
-  n_widgets = 0;
-  n_list_rows = 0;
-  //g_print ("ANCHOR: %u - %u\n", self->anchor_start, self->anchor_end);
-  for (tile = gtk_list_item_manager_get_first (self->item_manager);
-       tile;
-       tile = gtk_rb_tree_node_get_next (tile))
-    {
-      if (tile->widget)
-        n_widgets++;
-      n_list_rows++;
-      g_print ("  %4u%s %d,%d,%d,%d\n", tile->n_items, tile->widget ? " (widget)" : "",
-               tile->area.x, tile->area.y, tile->area.width, tile->area.height);
-    }
-
-  g_print ("  => %u widgets in %u list rows\n", n_widgets, n_list_rows);
-}
-
 static GtkListTile *
 gtk_list_view_split (GtkListBase *base,
                     GtkListTile *tile,
@@ -215,6 +194,13 @@ gtk_list_view_split (GtkListBase *base,
  return new_tile;
 }

+static void
+gtk_list_view_prepare_section (GtkListBase *base,
+                               GtkListTile *tile,
+                               guint        position)
+{
+}
+
 /* We define the listview as **inert** when the factory isn't used. */
 static gboolean
 gtk_list_view_is_inert (GtkListView *self)
@@ -228,7 +214,8 @@ gtk_list_view_is_inert (GtkListView *self)

 static void
 gtk_list_view_update_factories_with (GtkListView        *self,
-                                     GtkListItemFactory *factory)
+                                     GtkListItemFactory *factory,
+                                     GtkListItemFactory *header_factory)
 {
  GtkListTile *tile;

@@ -236,8 +223,27 @@ gtk_list_view_update_factories_with (GtkListView        *self,
       tile != NULL;
       tile = gtk_rb_tree_node_get_next (tile))
    {
-      if (tile->widget)
-        gtk_list_factory_widget_set_factory (GTK_LIST_FACTORY_WIDGET (tile->widget), factory);
+      switch (tile->type)
+        {
+        case GTK_LIST_TILE_ITEM:
+          if (tile->widget)
+            gtk_list_factory_widget_set_factory (GTK_LIST_FACTORY_WIDGET (tile->widget), factory);
+          break;
+        case GTK_LIST_TILE_HEADER:
+          if (tile->widget)
+            gtk_list_header_widget_set_factory (GTK_LIST_HEADER_WIDGET (tile->widget), header_factory);
+          break;
+        case GTK_LIST_TILE_UNMATCHED_HEADER:
+        case GTK_LIST_TILE_FOOTER:
+        case GTK_LIST_TILE_UNMATCHED_FOOTER:
+        case GTK_LIST_TILE_FILLER:
+        case GTK_LIST_TILE_REMOVED:
+          g_assert (tile->widget == NULL);
+          break;
+        default:
+          g_assert_not_reached();
+          break;
+        }
    }
 }

@@ -245,13 +251,14 @@ static void
 gtk_list_view_update_factories (GtkListView *self)
 {
  gtk_list_view_update_factories_with (self,
-                                       gtk_list_view_is_inert (self) ? NULL : self->factory);
+                                       gtk_list_view_is_inert (self) ? NULL : self->factory,
+                                       gtk_list_view_is_inert (self) ? NULL : self->header_factory);
 }

 static void
 gtk_list_view_clear_factories (GtkListView *self)
 {
-  gtk_list_view_update_factories_with (self, NULL);
+  gtk_list_view_update_factories_with (self, NULL, NULL);
 }

 static GtkListItemBase *
@@ -275,6 +282,20 @@ gtk_list_view_create_list_widget (GtkListBase *base)
  return GTK_LIST_ITEM_BASE (result);
 }

+static GtkListHeaderBase *
+gtk_list_view_create_header_widget (GtkListBase *base)
+{
+  GtkListView *self = GTK_LIST_VIEW (base);
+  GtkListItemFactory *factory;
+
+  if (gtk_list_view_is_inert (self))
+    factory = NULL;
+  else
+    factory = self->header_factory;
+
+  return GTK_LIST_HEADER_BASE (gtk_list_header_widget_new (factory));
+}
+
 static gboolean
 gtk_list_view_get_allocation (GtkListBase  *base,
                              guint         pos,
@@ -527,8 +548,11 @@ gtk_list_view_measure_list (GtkWidget      *widget,
          gtk_widget_measure (tile->widget,
                              orientation, for_size,
                              &child_min, &child_nat, NULL, NULL);
-          g_array_append_val (min_heights, child_min);
-          g_array_append_val (nat_heights, child_nat);
+          if (tile->type == GTK_LIST_TILE_ITEM)
+            {
+              g_array_append_val (min_heights, child_min);
+              g_array_append_val (nat_heights, child_nat);
+            }
          min += child_min;
          nat += child_nat;
        }
@@ -622,7 +646,8 @@ gtk_list_view_size_allocate (GtkWidget *widget,
      else
        row_height = nat;
      gtk_list_tile_set_area_size (self->item_manager, tile, list_width, row_height);
-      g_array_append_val (heights, row_height);
+      if (tile->type == GTK_LIST_TILE_ITEM)
+        g_array_append_val (heights, row_height);
    }

  /* step 3: determine height of unknown items and set the positions */
@@ -723,6 +748,10 @@ gtk_list_view_get_property (GObject    *object,
      g_value_set_object (value, self->factory);
      break;

+    case PROP_HEADER_FACTORY:
+      g_value_set_object (value, self->header_factory);
+      break;
+
    case PROP_MODEL:
      g_value_set_object (value, gtk_list_base_get_model (GTK_LIST_BASE (self)));
      break;
@@ -763,6 +792,10 @@ gtk_list_view_set_property (GObject      *object,
      gtk_list_view_set_factory (self, g_value_get_object (value));
      break;

+    case PROP_HEADER_FACTORY:
+      gtk_list_view_set_header_factory (self, g_value_get_object (value));
+      break;
+
    case PROP_MODEL:
      gtk_list_view_set_model (self, g_value_get_object (value));
      break;
@@ -812,6 +845,8 @@ gtk_list_view_class_init (GtkListViewClass *klass)

  list_base_class->split = gtk_list_view_split;
  list_base_class->create_list_widget = gtk_list_view_create_list_widget;
+  list_base_class->prepare_section = gtk_list_view_prepare_section;
+  list_base_class->create_header_widget = gtk_list_view_create_header_widget;
  list_base_class->get_allocation = gtk_list_view_get_allocation;
  list_base_class->get_items_in_rect = gtk_list_view_get_items_in_rect;
  list_base_class->get_position_from_allocation = gtk_list_view_get_position_from_allocation;
@@ -849,6 +884,18 @@ gtk_list_view_class_init (GtkListViewClass *klass)
                         GTK_TYPE_LIST_ITEM_FACTORY,
                         G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);

+  /**
+   * GtkListView:header-factory: (attributes org.gtk.Property.get=gtk_list_view_get_header_factory org.gtk.Property.set=gtk_list_view_set_header_factory)
+   *
+   * Factory for creating header widgets.
+   *
+   * Since: 4.12
+   */
+  properties[PROP_HEADER_FACTORY] =
+    g_param_spec_object ("header-factory", NULL, NULL,
+                         GTK_TYPE_LIST_ITEM_FACTORY,
+                         G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
  /**
   * GtkListView:model: (attributes org.gtk.Property.get=gtk_list_view_get_model org.gtk.Property.set=gtk_list_view_set_model)
   *
@@ -1070,6 +1117,68 @@ gtk_list_view_set_factory (GtkListView        *self,
  g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_FACTORY]);
 }

+/**
+ * gtk_list_view_get_header_factory: (attributes org.gtk.Method.get_property=header-factory)
+ * @self: a `GtkListView`
+ *
+ * Gets the factory that's currently used to populate section headers.
+ *
+ * Returns: (nullable) (transfer none): The factory in use
+ *
+ * Since: 4.12
+ */
+GtkListItemFactory *
+gtk_list_view_get_header_factory (GtkListView *self)
+{
+  g_return_val_if_fail (GTK_IS_LIST_VIEW (self), NULL);
+
+  return self->header_factory;
+}
+
+/**
+ * gtk_list_view_set_header_factory: (attributes org.gtk.Method.set_property=header-factory)
+ * @self: a `GtkListView`
+ * @factory: (nullable) (transfer none): the factory to use
+ *
+ * Sets the `GtkListItemFactory` to use for populating the
+ * [class@Gtk.ListHeader] objects used in section headers.
+ *
+ * If this factory is set to %NULL, the list will not show section headers.
+ *
+ * Since: 4.12
+ */
+void
+gtk_list_view_set_header_factory (GtkListView        *self,
+                                  GtkListItemFactory *factory)
+{
+  gboolean had_sections;
+
+  g_return_if_fail (GTK_IS_LIST_VIEW (self));
+  g_return_if_fail (factory == NULL || GTK_IS_LIST_ITEM_FACTORY (factory));
+
+  had_sections = gtk_list_item_manager_get_has_sections (self->item_manager);
+
+  if (!g_set_object (&self->header_factory, factory))
+    return;
+
+  gtk_list_item_manager_set_has_sections (self->item_manager, factory != NULL);
+
+  if (had_sections && gtk_list_item_manager_get_has_sections (self->item_manager))
+    {
+      GtkListTile *tile;
+
+      for (tile = gtk_list_item_manager_get_first (self->item_manager);
+           tile != NULL;
+           tile = gtk_rb_tree_node_get_next (tile))
+        {
+          if (tile->widget && tile->type == GTK_LIST_TILE_HEADER)
+            gtk_list_header_widget_set_factory (GTK_LIST_HEADER_WIDGET (tile->widget), factory);
+        }
+    }
+
+  g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_HEADER_FACTORY]);
+}
+
 /**
 * gtk_list_view_set_show_separators: (attributes org.gtk.Method.set_property=show-separators)
 * @self: a `GtkListView`
@@ -1139,7 +1248,7 @@ gtk_list_view_set_single_click_activate (GtkListView *self,
       tile != NULL;
       tile = gtk_rb_tree_node_get_next (tile))
    {
-      if (tile->widget)
+      if (tile->widget && tile->type == GTK_LIST_TILE_ITEM)
        gtk_list_factory_widget_set_single_click_activate (GTK_LIST_FACTORY_WIDGET (tile->widget), single_click_activate);
    }

--- a/gtk/gtklistview.h
+++ b/gtk/gtklistview.h
@@ -57,6 +57,13 @@ GDK_AVAILABLE_IN_ALL
 GtkListItemFactory *
                gtk_list_view_get_factory                       (GtkListView            *self);

+GDK_AVAILABLE_IN_4_12
+void            gtk_list_view_set_header_factory                (GtkListView            *self,
+                                                                 GtkListItemFactory     *factory);
+GDK_AVAILABLE_IN_4_12
+GtkListItemFactory *
+                gtk_list_view_get_header_factory                (GtkListView            *self);
+
 GDK_AVAILABLE_IN_ALL
 void            gtk_list_view_set_show_separators               (GtkListView            *self,
                                                                 gboolean                show_separators);
--- a/gtk/gtklistviewprivate.h
+++ b/gtk/gtklistviewprivate.h
@@ -30,6 +30,7 @@ struct _GtkListView

  GtkListItemManager *item_manager;
  GtkListItemFactory *factory;
+  GtkListItemFactory *header_factory;
  gboolean show_separators;
  gboolean single_click_activate;
 };
--- a/gtk/gtkmultiselection.c
+++ b/gtk/gtkmultiselection.c
@@ -22,6 +22,7 @@
 #include "gtkmultiselection.h"

 #include "gtkbitset.h"
+#include "gtksectionmodelprivate.h"
 #include "gtkselectionmodel.h"

 /**
@@ -94,6 +95,23 @@ gtk_multi_selection_list_model_init (GListModelInterface *iface)
  iface->get_item = gtk_multi_selection_get_item;
 }

+static void
+gtk_multi_selection_get_section (GtkSectionModel *model,
+                                 guint            position,
+                                 guint           *out_start,
+                                 guint           *out_end)
+{
+  GtkMultiSelection *self = GTK_MULTI_SELECTION (model);
+
+  gtk_list_model_get_section (self->model, position, out_start, out_end);
+}
+
+static void
+gtk_multi_selection_section_model_init (GtkSectionModelInterface *iface)
+{
+  iface->get_section = gtk_multi_selection_get_section;
+}
+
 static gboolean
 gtk_multi_selection_is_selected (GtkSelectionModel *model,
                                 guint              position)
@@ -205,6 +223,8 @@ gtk_multi_selection_selection_model_init (GtkSelectionModelInterface *iface)
 G_DEFINE_TYPE_EXTENDED (GtkMultiSelection, gtk_multi_selection, G_TYPE_OBJECT, 0,
                        G_IMPLEMENT_INTERFACE (G_TYPE_LIST_MODEL,
                                               gtk_multi_selection_list_model_init)
+                        G_IMPLEMENT_INTERFACE (GTK_TYPE_SECTION_MODEL,
+                                               gtk_multi_selection_section_model_init)
                        G_IMPLEMENT_INTERFACE (GTK_TYPE_SELECTION_MODEL,
                                               gtk_multi_selection_selection_model_init))

--- a/gtk/gtknoselection.c
+++ b/gtk/gtknoselection.c
@@ -22,6 +22,7 @@
 #include "gtknoselection.h"

 #include "gtkbitset.h"
+#include "gtksectionmodelprivate.h"
 #include "gtkselectionmodel.h"

 /**
@@ -92,6 +93,23 @@ gtk_no_selection_list_model_init (GListModelInterface *iface)
  iface->get_item = gtk_no_selection_get_item;
 }

+static void
+gtk_no_selection_get_section (GtkSectionModel *model,
+                              guint            position,
+                              guint           *out_start,
+                              guint           *out_end)
+{
+  GtkNoSelection *self = GTK_NO_SELECTION (model);
+
+  gtk_list_model_get_section (self->model, position, out_start, out_end);
+}
+
+static void
+gtk_no_selection_section_model_init (GtkSectionModelInterface *iface)
+{
+  iface->get_section = gtk_no_selection_get_section;
+}
+
 static gboolean
 gtk_no_selection_is_selected (GtkSelectionModel *model,
                              guint              position)
@@ -117,6 +135,8 @@ gtk_no_selection_selection_model_init (GtkSelectionModelInterface *iface)
 G_DEFINE_TYPE_EXTENDED (GtkNoSelection, gtk_no_selection, G_TYPE_OBJECT, 0,
                        G_IMPLEMENT_INTERFACE (G_TYPE_LIST_MODEL,
                                               gtk_no_selection_list_model_init)
+                        G_IMPLEMENT_INTERFACE (GTK_TYPE_SECTION_MODEL,
+                                               gtk_no_selection_section_model_init)
                        G_IMPLEMENT_INTERFACE (GTK_TYPE_SELECTION_MODEL,
                                               gtk_no_selection_selection_model_init))

--- a/gtk/gtksectionmodel.c
+++ b/gtk/gtksectionmodel.c
@@ -0,0 +1,225 @@
+/*
+ * Copyright © 2022 Benjamin Otte
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Benjamin Otte <otte@gnome.org>
+ */
+
+#include "config.h"
+
+#include "gtksectionmodelprivate.h"
+
+#include "gtkmarshalers.h"
+
+/**
+ * GtkSectionModel:
+ *
+ * `GtkSectionModel` is an interface that adds support for section to list models.
+ *
+ * This support is then used by widgets using list models to be able to group their
+ * items into sections.
+ *
+ * Many GTK list models support sections inherently, or they pass through the sections
+ * of a model they are wrapping.
+ *
+ * A `GtkSectionModel` groups successive items into so-called sections. List widgets
+ * like `GtkListView` then allow displaying section headers for these sections.
+ *
+ * When the section groupings of a model changes, the model will emit the
+ * [signal@Gtk.SectionModel::sections-changed] signal by calling the
+ * [method@Gtk.SectionModel.sections_changed] function. All sections in the given range
+ * now need to be queried again.  
+ * The [signal@Gio.ListModel::items-changed] signal has the same effect, all sections in
+ * that range are invalidated, too.
+ *
+ * Since: 4.12
+ */
+
+G_DEFINE_INTERFACE (GtkSectionModel, gtk_section_model, G_TYPE_LIST_MODEL)
+
+enum {
+  SECTIONS_CHANGED,
+  LAST_SIGNAL
+};
+
+static guint signals[LAST_SIGNAL] = { 0 };
+
+static void
+gtk_section_model_default_get_section (GtkSectionModel *self,
+                                       guint            position,
+                                       guint           *out_start,
+                                       guint           *out_end)
+{
+  guint n_items = g_list_model_get_n_items (G_LIST_MODEL (self));
+
+  if (position >= n_items)
+    {
+      *out_start = n_items;
+      *out_end = G_MAXUINT;
+    }
+
+  *out_start = 0;
+  *out_end = n_items;
+}
+
+static void
+gtk_section_model_default_init (GtkSectionModelInterface *iface)
+{
+  iface->get_section = gtk_section_model_default_get_section;
+
+  /**
+   * GtkSectionModel::sections-changed
+   * @model: a `GtkSectionModel`
+   * @position: The first item that may have changed
+   * @n_items: number of items with changes
+   *
+   * Emitted when the start-of-section state of some of the items in @model changes.
+   *
+   * Note that this signal does not specify the new section state of the
+   * items, they need to be queried manually. It is also not necessary for
+   * a model to change the section state of any of the items in the section
+   * model, though it would be rather useless to emit such a signal.
+   *
+   * The [signal@Gio.ListModel::items-changed] implies the effect of the
+   * [signal@Gtk.SectionModel::sections-changed] signal for all the items
+   * it covers.
+   *
+   * Since: 4.12
+   */
+  signals[SECTIONS_CHANGED] =
+    g_signal_new ("sections-changed",
+                  GTK_TYPE_SECTION_MODEL,
+                  G_SIGNAL_RUN_LAST,
+                  0,
+                  NULL, NULL,
+                  _gtk_marshal_VOID__UINT_UINT,
+                  G_TYPE_NONE, 2, G_TYPE_UINT, G_TYPE_UINT);
+  g_signal_set_va_marshaller (signals[SECTIONS_CHANGED],
+                              GTK_TYPE_SECTION_MODEL,
+                              _gtk_marshal_VOID__UINT_UINTv);
+}
+
+/**
+ * gtk_section_model_get_section:
+ * @self: a `GtkSectionModel`
+ * @position: the position of the item to query
+ * @out_start: (out caller-allocates): the position of the first
+ *   item in the section
+ * @out_end: (out caller-allocates): the position of the first
+ *   item not part of the section anymore.
+ *
+ * Query the section that covers the given position. The number of
+ * items in the section can be computed by `out_end - out_start`.
+ *
+ * If the position is larger than the number of items, a single
+ * range from n_items to G_MAXUINT will be returned.
+ *
+ * Since: 4.12
+ */
+void
+gtk_section_model_get_section (GtkSectionModel *self,
+                               guint            position,
+                               guint           *out_start,
+                               guint           *out_end)
+{
+  GtkSectionModelInterface *iface;
+
+  g_return_if_fail (GTK_IS_SECTION_MODEL (self));
+  g_return_if_fail (out_start != NULL);
+  g_return_if_fail (out_end != NULL);
+
+  iface = GTK_SECTION_MODEL_GET_IFACE (self);
+  iface->get_section (self, position, out_start, out_end);
+
+  g_warn_if_fail (*out_start < *out_end);
+}
+
+/* A version of gtk_section_model_get_section() that handles NULL
+ * (treats it as the empty list) and any GListModel (treats it as
+ * a single section).
+ **/
+void
+gtk_list_model_get_section (GListModel *self,
+                            guint       position,
+                            guint      *out_start,
+                            guint      *out_end)
+{
+  g_return_if_fail (out_start != NULL);
+  g_return_if_fail (out_end != NULL);
+
+  if (self == NULL)
+    {
+      *out_start = 0;
+      *out_end = G_MAXUINT;
+      return;
+    }
+
+  g_return_if_fail (G_IS_LIST_MODEL (self));
+
+  if (!GTK_IS_SECTION_MODEL (self))
+    {
+      guint n_items = g_list_model_get_n_items (self);
+
+      if (position < n_items)
+        {
+          *out_start = 0;
+          *out_end = G_MAXUINT;
+        }
+      else
+        {
+          *out_start = n_items;
+          *out_end = G_MAXUINT;
+        }
+
+      return;
+    }
+
+  gtk_section_model_get_section (GTK_SECTION_MODEL (self), position, out_start, out_end);
+}
+
+/**
+ * gtk_section_model_section_changed:
+ * @self: a `GtkSectionModel`
+ * @position: the first changed item
+ * @n_items: the number of changed items
+ *
+ * This function emits the [signal@Gtk.SectionModel::section-changed]
+ * signal to notify about changes to sections. It must cover all
+ * positions that used to be a section start or that are now a section
+ * start. It does not have to cover all positions for which the section
+ * has changed.
+ *
+ * The [signal@Gio.ListModel::items-changed] implies the effect of the
+ * [signal@Gtk.SectionModel::section-changed] signal for all the items
+ * it covers.
+ *
+ * It is recommended that when changes to the items cause section changes
+ * in a larger range, that the larger range is included in the emission
+ * of the [signal@Gio.ListModel::items-changed] instead of emitting
+ * two signals.
+ *
+ * Since: 4.12
+ */
+void
+gtk_section_model_sections_changed (GtkSectionModel *self,
+                                    guint            position,
+                                    guint            n_items)
+{
+  g_return_if_fail (GTK_IS_SECTION_MODEL (self));
+  g_return_if_fail (n_items > 0);
+  g_return_if_fail (position + n_items <= g_list_model_get_n_items (G_LIST_MODEL (self)));
+
+  g_signal_emit (self, signals[SECTIONS_CHANGED], 0, position, n_items);
+}
--- a/gtk/gtksectionmodel.h
+++ b/gtk/gtksectionmodel.h
@@ -0,0 +1,72 @@
+/*
+ * Copyright © 2022 Benjamin Otte
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Benjamin Otte <otte@gnome.org>
+ */
+
+#pragma once
+
+#if !defined (__GTK_H_INSIDE__) && !defined (GTK_COMPILATION)
+#error "Only <gtk/gtk.h> can be included directly."
+#endif
+
+#include <gtk/gtktypes.h>
+
+G_BEGIN_DECLS
+
+#define GTK_TYPE_SECTION_MODEL       (gtk_section_model_get_type ())
+
+GDK_AVAILABLE_IN_4_12
+G_DECLARE_INTERFACE (GtkSectionModel, gtk_section_model, GTK, SECTION_MODEL, GListModel)
+
+/**
+ * GtkSectionModelInterface:
+ * @get_section: Return the section that covers the given position. If
+ *   the position is outside the number of items, returns a single range from
+ *   n_items to G_MAXUINT
+ *
+ * The list of virtual functions for the `GtkSectionModel` interface.
+ * No function must be implemented, but unless `GtkSectionModel::get_section()`
+ * is implemented, the whole model will just be a single section.
+ *
+ * Since: 4.12
+ */
+struct _GtkSectionModelInterface
+{
+  /*< private >*/
+  GTypeInterface g_iface;
+
+  /*< public >*/
+  void                  (* get_section)                         (GtkSectionModel      *self,
+                                                                 guint                 position,
+                                                                 guint                *out_start,
+                                                                 guint                *out_end);
+};
+
+GDK_AVAILABLE_IN_4_12
+void                    gtk_section_model_get_section           (GtkSectionModel      *self,
+                                                                 guint                 position,
+                                                                 guint                *out_start,
+                                                                 guint                *out_end);
+
+/* for implementations only */
+GDK_AVAILABLE_IN_4_12
+void                    gtk_section_model_sections_changed      (GtkSectionModel      *self,
+                                                                 guint                 position,
+                                                                 guint                 n_items);
+
+G_END_DECLS
+
--- a/gtk/gtksectionmodelprivate.h
+++ b/gtk/gtksectionmodelprivate.h
@@ -0,0 +1,14 @@
+#pragma once
+
+#include "gtksectionmodel.h"
+
+G_BEGIN_DECLS
+
+void                    gtk_list_model_get_section              (GListModel           *self,
+                                                                 guint                 position,
+                                                                 guint                *out_start,
+                                                                 guint                *out_end);
+
+
+G_END_DECLS
+
--- a/gtk/gtksingleselection.c
+++ b/gtk/gtksingleselection.c
@@ -22,6 +22,7 @@
 #include "gtksingleselection.h"

 #include "gtkbitset.h"
+#include "gtksectionmodelprivate.h"
 #include "gtkselectionmodel.h"

 /**
@@ -103,6 +104,23 @@ gtk_single_selection_list_model_init (GListModelInterface *iface)
  iface->get_item = gtk_single_selection_get_item;
 }

+static void
+gtk_single_selection_get_section (GtkSectionModel *model,
+                                  guint            position,
+                                  guint           *out_start,
+                                  guint           *out_end)
+{
+  GtkSingleSelection *self = GTK_SINGLE_SELECTION (model);
+
+  gtk_list_model_get_section (self->model, position, out_start, out_end);
+}
+
+static void
+gtk_single_selection_section_model_init (GtkSectionModelInterface *iface)
+{
+  iface->get_section = gtk_single_selection_get_section;
+}
+
 static gboolean
 gtk_single_selection_is_selected (GtkSelectionModel *model,
                                  guint              position)
@@ -167,6 +185,8 @@ gtk_single_selection_selection_model_init (GtkSelectionModelInterface *iface)
 G_DEFINE_TYPE_EXTENDED (GtkSingleSelection, gtk_single_selection, G_TYPE_OBJECT, 0,
                        G_IMPLEMENT_INTERFACE (G_TYPE_LIST_MODEL,
                                               gtk_single_selection_list_model_init)
+                        G_IMPLEMENT_INTERFACE (GTK_TYPE_SECTION_MODEL,
+                                               gtk_single_selection_section_model_init)
                        G_IMPLEMENT_INTERFACE (GTK_TYPE_SELECTION_MODEL,
                                               gtk_single_selection_selection_model_init))

--- a/gtk/gtksortlistmodel.c
+++ b/gtk/gtksortlistmodel.c
@@ -22,7 +22,9 @@
 #include "gtksortlistmodel.h"

 #include "gtkbitset.h"
+#include "gtkmultisorter.h"
 #include "gtkprivate.h"
+#include "gtksectionmodel.h"
 #include "gtksorterprivate.h"
 #include "timsort/gtktimsortprivate.h"

@@ -73,6 +75,13 @@
 * If you run into performance issues with `GtkSortListModel`,
 * it is strongly recommended that you write your own sorting list
 * model.
+ *
+ * `GtkSortListModel` allows sorting the items into sections. It
+ * implements `GtkSectionModel` and when [property@Gtk.SortListModel:section-sorter]
+ * is set, it will sort all items with that sorter and items comparing
+ * equal with it will be put into the same section.
+ * The [property@Gtk.SortListModel:sorter] will then be used to sort items
+ * inside their sections.
 */

 enum {
@@ -82,6 +91,7 @@ enum {
  PROP_MODEL,
  PROP_N_ITEMS,
  PROP_PENDING,
+  PROP_SECTION_SORTER,
  PROP_SORTER,
  NUM_PROPERTIES
 };
@@ -92,6 +102,8 @@ struct _GtkSortListModel

  GListModel *model;
  GtkSorter *sorter;
+  GtkSorter *section_sorter;
+  GtkSorter *real_sorter;
  gboolean incremental;

  GtkTimSort sort; /* ongoing sort operation */
@@ -99,6 +111,7 @@ struct _GtkSortListModel

  guint n_items;
  GtkSortKeys *sort_keys;
+  GtkSortKeys *section_sort_keys; /* we assume they are compatible with the sort keys because they're the first element */
  gsize key_size;
  gpointer keys;
  GtkBitset *missing_keys;
@@ -174,8 +187,159 @@ gtk_sort_list_model_model_init (GListModelInterface *iface)
  iface->get_item = gtk_sort_list_model_get_item;
 }

+static void
+gtk_sort_list_model_ensure_key (GtkSortListModel *self,
+                                guint             pos)
+{
+  gpointer item;
+
+  if (!gtk_bitset_contains (self->missing_keys, pos))
+    return;
+
+ item = g_list_model_get_item (self->model, pos);
+ gtk_sort_keys_init_key (self->sort_keys, item, key_from_pos (self, pos));
+ g_object_unref (item);
+
+  gtk_bitset_remove (self->missing_keys, pos);
+}
+
+static void
+gtk_sort_list_model_get_section_unsorted (GtkSortListModel *self,
+                                          guint             position,
+                                          guint            *out_start,
+                                          guint            *out_end)
+{
+  gpointer *pos, *start, *end;
+
+  pos = &self->positions[position];
+  gtk_sort_list_model_ensure_key (self, pos_from_key (self, *pos));
+
+  for (start = pos;
+       start > self->positions;
+       start--)
+    {
+      gtk_sort_list_model_ensure_key (self, pos_from_key (self, start[-1]));
+      if (gtk_sort_keys_compare (self->section_sort_keys, start[-1], *pos) != GTK_ORDERING_EQUAL)
+        break;
+    }
+
+  for (end = pos + 1;
+       end < &self->positions[self->n_items];
+       end++)
+    {
+      gtk_sort_list_model_ensure_key (self, pos_from_key (self, *end));
+      if (gtk_sort_keys_compare (self->section_sort_keys, *end, *pos) != GTK_ORDERING_EQUAL)
+        break;
+    }
+
+  *out_start = start - self->positions;
+  *out_end = end - self->positions;
+}
+
+static void
+gtk_sort_list_model_get_section_sorted (GtkSortListModel *self,
+                                        guint             position,
+                                        guint            *out_start,
+                                        guint            *out_end)
+{
+  gpointer *pos;
+  guint step, min, max, mid;
+
+  pos = &self->positions[position];
+  
+  max = position;
+  step = 1;
+  while (max > 0)
+    {
+      min = max - MIN (max, step);
+      step *= 2;
+      if (gtk_sort_keys_compare (self->section_sort_keys, self->positions[min], *pos) == GTK_ORDERING_EQUAL)
+        {
+          max = min;
+          continue;
+        }
+      /* now min is different, max is equal, bsearch where that changes */
+      while (max - min > 1)
+        {
+          mid = (max + min) / 2;
+          if (gtk_sort_keys_compare (self->section_sort_keys, self->positions[mid], *pos) == GTK_ORDERING_EQUAL)
+            max = mid;
+          else
+            min = mid;
+        }
+      break;
+    }
+  *out_start = max;
+
+  min = position;
+  step = 1;
+  while (min < self->n_items - 1)
+    {
+      max = min + MIN (self->n_items - 1 - min, step);
+      step *= 2;
+      if (gtk_sort_keys_compare (self->section_sort_keys, self->positions[max], *pos) == GTK_ORDERING_EQUAL)
+        {
+          min = max;
+          continue;
+        }
+      /* now min is equal, max is different, bsearch where that changes */
+      while (max - min > 1)
+        {
+          mid = (max + min) / 2;
+          if (gtk_sort_keys_compare (self->section_sort_keys, self->positions[mid], *pos) == GTK_ORDERING_EQUAL)
+            min = mid;
+          else
+            max = mid;
+        }
+      break;
+    }
+  *out_end = min + 1;
+}
+
+static void
+gtk_sort_list_model_get_section (GtkSectionModel *model,
+                                 guint            position,
+                                 guint           *out_start,
+                                 guint           *out_end)
+{
+  GtkSortListModel *self = GTK_SORT_LIST_MODEL (model);
+
+  if (position >= self->n_items)
+    {
+      *out_start = self->n_items;
+      *out_end = G_MAXUINT;
+      return;
+    }
+
+  if (self->section_sort_keys == NULL)
+    {
+      *out_start = 0;
+      *out_end = self->n_items;
+      return;
+    }
+
+  /* When the list is not sorted:
+   * - keys may not exist yet
+   * - equal items may not be adjacent
+   * So add a slow path that can deal with that, but is O(N).
+   * The fast path is O(log N) and will be used for I guess
+   * 99% of cases.
+   */
+  if (self->sort_cb)
+    gtk_sort_list_model_get_section_unsorted (self, position, out_start, out_end);
+  else
+    gtk_sort_list_model_get_section_sorted (self, position, out_start, out_end);
+}
+
+static void
+gtk_sort_list_model_section_model_init (GtkSectionModelInterface *iface)
+{
+  iface->get_section = gtk_sort_list_model_get_section;
+}
+
 G_DEFINE_TYPE_WITH_CODE (GtkSortListModel, gtk_sort_list_model, G_TYPE_OBJECT,
-                         G_IMPLEMENT_INTERFACE (G_TYPE_LIST_MODEL, gtk_sort_list_model_model_init))
+                         G_IMPLEMENT_INTERFACE (G_TYPE_LIST_MODEL, gtk_sort_list_model_model_init)
+                         G_IMPLEMENT_INTERFACE (GTK_TYPE_SECTION_MODEL, gtk_sort_list_model_section_model_init))

 static gboolean
 gtk_sort_list_model_is_sorting (GtkSortListModel *self)
@@ -379,6 +543,7 @@ gtk_sort_list_model_clear_keys (GtkSortListModel *self)
  g_clear_pointer (&self->missing_keys, gtk_bitset_unref);
  g_clear_pointer (&self->keys, g_free);
  g_clear_pointer (&self->sort_keys, gtk_sort_keys_unref);
+  g_clear_pointer (&self->section_sort_keys, gtk_sort_keys_unref);
  self->key_size = 0;
 }

@@ -426,9 +591,9 @@ gtk_sort_list_model_clear_items (GtkSortListModel *self,
 static gboolean
 gtk_sort_list_model_should_sort (GtkSortListModel *self)
 {
-  return self->sorter != NULL &&
+  return self->real_sorter != NULL &&
         self->model != NULL &&
-         gtk_sorter_get_order (self->sorter) != GTK_SORTER_ORDER_NONE;
+         gtk_sorter_get_order (self->real_sorter) != GTK_SORTER_ORDER_NONE;
 }

 static void
@@ -436,9 +601,12 @@ gtk_sort_list_model_create_keys (GtkSortListModel *self)
 {
  g_assert (self->keys == NULL);
  g_assert (self->sort_keys == NULL);
+  g_assert (self->section_sort_keys == NULL);
  g_assert (self->key_size == 0);

-  self->sort_keys = gtk_sorter_get_keys (self->sorter);
+  self->sort_keys = gtk_sorter_get_keys (self->real_sorter);
+  if (self->section_sorter)
+    self->section_sort_keys = gtk_sorter_get_keys (self->section_sorter);
  self->key_size = gtk_sort_keys_get_key_size (self->sort_keys);
  self->keys = g_malloc_n (self->n_items, self->key_size);
  self->missing_keys = gtk_bitset_new_range (0, self->n_items);
@@ -646,6 +814,10 @@ gtk_sort_list_model_set_property (GObject      *object,
      gtk_sort_list_model_set_model (self, g_value_get_object (value));
      break;

+    case PROP_SECTION_SORTER:
+      gtk_sort_list_model_set_section_sorter (self, g_value_get_object (value));
+      break;
+
    case PROP_SORTER:
      gtk_sort_list_model_set_sorter (self, g_value_get_object (value));
      break;
@@ -686,6 +858,10 @@ gtk_sort_list_model_get_property (GObject     *object,
      g_value_set_uint (value, gtk_sort_list_model_get_pending (self));
      break;

+    case PROP_SECTION_SORTER:
+      g_value_set_object (value, self->section_sorter);
+      break;
+
    case PROP_SORTER:
      g_value_set_object (value, self->sorter);
      break;
@@ -763,13 +939,42 @@ gtk_sort_list_model_clear_model (GtkSortListModel *self)
 }

 static void
-gtk_sort_list_model_clear_sorter (GtkSortListModel *self)
+gtk_sort_list_model_clear_real_sorter (GtkSortListModel *self)
 {
-  if (self->sorter == NULL)
+  if (self->real_sorter == NULL)
    return;

-  g_signal_handlers_disconnect_by_func (self->sorter, gtk_sort_list_model_sorter_changed_cb, self);
-  g_clear_object (&self->sorter);
+  g_signal_handlers_disconnect_by_func (self->real_sorter, gtk_sort_list_model_sorter_changed_cb, self);
+  g_clear_object (&self->real_sorter);
+}
+
+static void
+gtk_sort_list_model_ensure_real_sorter (GtkSortListModel *self)
+{
+  if (self->sorter)
+    {
+      if (self->section_sorter)
+        {
+          GtkMultiSorter *multi;
+
+          multi = gtk_multi_sorter_new ();
+          self->real_sorter = GTK_SORTER (multi);
+          gtk_multi_sorter_append (multi, g_object_ref (self->section_sorter));
+          gtk_multi_sorter_append (multi, g_object_ref (self->sorter));
+        }
+      else
+        self->real_sorter = g_object_ref (self->sorter);
+    }
+  else
+    {
+      if (self->section_sorter)
+        self->real_sorter = g_object_ref (self->section_sorter);
+    }
+
+  if (self->real_sorter)
+    g_signal_connect (self->real_sorter, "changed", G_CALLBACK (gtk_sort_list_model_sorter_changed_cb), self);
+
+  gtk_sort_list_model_sorter_changed_cb (self->real_sorter, GTK_SORTER_CHANGE_DIFFERENT, self);
 }

 static void
@@ -778,7 +983,9 @@ gtk_sort_list_model_dispose (GObject *object)
  GtkSortListModel *self = GTK_SORT_LIST_MODEL (object);

  gtk_sort_list_model_clear_model (self);
-  gtk_sort_list_model_clear_sorter (self);
+  gtk_sort_list_model_clear_real_sorter (self);
+  g_clear_object (&self->section_sorter);
+  g_clear_object (&self->sorter);

  G_OBJECT_CLASS (gtk_sort_list_model_parent_class)->dispose (object);
 };
@@ -846,6 +1053,18 @@ gtk_sort_list_model_class_init (GtkSortListModelClass *class)
                         0, G_MAXUINT, 0,
                         GTK_PARAM_READABLE | G_PARAM_EXPLICIT_NOTIFY);

+  /**
+   * GtkSortListModel:section-sorter: (attributes org.gtk.Property.get=gtk_sort_list_model_get_section_sorter org.gtk.Property.set=gtk_sort_list_model_set_section_sorter)
+   *
+   * The section sorter for this model, if one is set.
+   *
+   * Since: 4.12
+   */
+  properties[PROP_SECTION_SORTER] =
+      g_param_spec_object ("section-sorter", NULL, NULL,
+                           GTK_TYPE_SORTER,
+                           GTK_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY);
+
  /**
   * GtkSortListModel:sorter: (attributes org.gtk.Property.get=gtk_sort_list_model_get_sorter org.gtk.Property.set=gtk_sort_list_model_set_sorter)
   *
@@ -972,15 +1191,16 @@ gtk_sort_list_model_set_sorter (GtkSortListModel *self,
  g_return_if_fail (GTK_IS_SORT_LIST_MODEL (self));
  g_return_if_fail (sorter == NULL || GTK_IS_SORTER (sorter));

-  gtk_sort_list_model_clear_sorter (self);
+  if (self->sorter == sorter)
+    return;
+
+  gtk_sort_list_model_clear_real_sorter (self);
+  g_clear_object (&self->sorter);

  if (sorter)
-    {
-      self->sorter = g_object_ref (sorter);
-      g_signal_connect (sorter, "changed", G_CALLBACK (gtk_sort_list_model_sorter_changed_cb), self);
-    }
+    self->sorter = g_object_ref (sorter);

-  gtk_sort_list_model_sorter_changed_cb (sorter, GTK_SORTER_CHANGE_DIFFERENT, self);
+  gtk_sort_list_model_ensure_real_sorter (self);

  g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_SORTER]);
 }
@@ -1001,6 +1221,55 @@ gtk_sort_list_model_get_sorter (GtkSortListModel *self)
  return self->sorter;
 }

+/**
+ * gtk_sort_list_model_set_section_sorter: (attributes org.gtk.Method.set_property=section-sorter)
+ * @self: a `GtkSortListModel`
+ * @sorter: (nullable): the `GtkSorter` to sort @model with
+ *
+ * Sets a new section sorter on @self.
+ *
+ * Since: 4.12
+ */
+void
+gtk_sort_list_model_set_section_sorter (GtkSortListModel *self,
+                                        GtkSorter        *sorter)
+{
+  g_return_if_fail (GTK_IS_SORT_LIST_MODEL (self));
+  g_return_if_fail (sorter == NULL || GTK_IS_SORTER (sorter));
+
+  if (self->section_sorter == sorter)
+    return;
+
+  gtk_sort_list_model_clear_real_sorter (self);
+  g_clear_object (&self->section_sorter);
+
+  if (sorter)
+    self->section_sorter = g_object_ref (sorter);
+
+  gtk_sort_list_model_ensure_real_sorter (self);
+
+  g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_SECTION_SORTER]);
+}
+
+/**
+ * gtk_sort_list_model_get_section_sorter: (attributes org.gtk.Method.get_property=section-sorter)
+ * @self: a `GtkSortListModel`
+ *
+ * Gets the section sorter that is used to sort items of @self into
+ * sections.
+ *
+ * Returns: (nullable) (transfer none): the sorter of #self
+ *
+ * Since: 4.12
+ */
+GtkSorter *
+gtk_sort_list_model_get_section_sorter (GtkSortListModel *self)
+{
+  g_return_val_if_fail (GTK_IS_SORT_LIST_MODEL (self), NULL);
+
+  return self->section_sorter;
+}
+
 /**
 * gtk_sort_list_model_set_incremental: (attributes org.gtk.Method.set_property=incremental)
 * @self: a `GtkSortListModel`
--- a/gtk/gtksortlistmodel.h
+++ b/gtk/gtksortlistmodel.h
@@ -45,6 +45,12 @@ void                    gtk_sort_list_model_set_sorter          (GtkSortListMode
 GDK_AVAILABLE_IN_ALL
 GtkSorter *             gtk_sort_list_model_get_sorter          (GtkSortListModel       *self);

+GDK_AVAILABLE_IN_4_12
+void                    gtk_sort_list_model_set_section_sorter  (GtkSortListModel       *self,
+                                                                 GtkSorter              *sorter);
+GDK_AVAILABLE_IN_4_12
+GtkSorter *             gtk_sort_list_model_get_section_sorter  (GtkSortListModel       *self);
+
 GDK_AVAILABLE_IN_ALL
 void                    gtk_sort_list_model_set_model           (GtkSortListModel       *self,
                                                                 GListModel             *model);
--- a/gtk/meson.build
+++ b/gtk/meson.build
@@ -271,6 +271,9 @@ gtk_public_sources = files([
  'gtklinkbutton.c',
  'gtklistbox.c',
  'gtklistfactorywidget.c',
+  'gtklistheader.c',
+  'gtklistheaderbase.c',
+  'gtklistheaderwidget.c',
  'gtklistitem.c',
  'gtklistitembase.c',
  'gtklistitemfactory.c',
@@ -333,6 +336,7 @@ gtk_public_sources = files([
  'gtkscrolledwindow.c',
  'gtksearchbar.c',
  'gtksearchentry.c',
+  'gtksectionmodel.c',
  'gtkselectionfiltermodel.c',
  'gtkselectionmodel.c',
  'gtkseparator.c',
@@ -518,6 +522,7 @@ gtk_public_headers = files([
  'gtklinkbutton.h',
  'gtklistbase.h',
  'gtklistbox.h',
+  'gtklistheader.h',
  'gtklistitem.h',
  'gtklistitemfactory.h',
  'gtklistview.h',
@@ -565,6 +570,7 @@ gtk_public_headers = files([
  'gtkscrolledwindow.h',
  'gtksearchbar.h',
  'gtksearchentry.h',
+  'gtksectionmodel.h',
  'gtkselectionfiltermodel.h',
  'gtkselectionmodel.h',
  'gtkseparator.h',
--- a/gtk/theme/Default/_common.scss
+++ b/gtk/theme/Default/_common.scss
@@ -3371,7 +3371,7 @@ columnview row:not(:selected) cell editablelabel.editing text selection {


 .rich-list { /* rich lists usually containing other widgets than just labels/text */
-  & > row {
+  & > row, & > header {
    padding: 8px 12px;
    min-height: 32px; /* should be tall even when only containing a label */

@@ -3379,6 +3379,14 @@ columnview row:not(:selected) cell editablelabel.editing text selection {
      border-spacing: 12px;
    }
  }
+  & > header {
+    @extend %osd;
+    background-color: $osd_bg_color;
+
+    border-bottom: 1px solid $borders-color;
+    border-top: 1px solid $borders-color;
+    font-weight: bold;
+  }
 }

 /********************************************************
--- a/testsuite/gtk/filterlistmodel-exhaustive.c
+++ b/testsuite/gtk/filterlistmodel-exhaustive.c
@@ -43,6 +43,23 @@
    } \
 }G_STMT_END

+#define assert_sections_equal(model1, model2) G_STMT_START{ \
+  guint _i, _n, _start1, _end1, _start2, _end2; \
+  g_assert_cmpint (g_list_model_get_n_items (G_LIST_MODEL (model1)), ==, g_list_model_get_n_items (G_LIST_MODEL (model2))); \
+  _n = g_list_model_get_n_items (G_LIST_MODEL (model1)); \
+  for (_i = 0; _i < _n; _i = _end1) \
+    { \
+      gtk_section_model_get_section (model1, _i, &_start1, &_end1); \
+      gtk_section_model_get_section (model2, _i, &_start2, &_end2); \
+      g_assert_cmpint (_start1, <, _end1); \
+      g_assert_cmpint (_start2, <, _end2); \
+      g_assert_cmpint (_start1, ==, _start2); \
+      g_assert_cmpint (_end1, ==, _end2); \
+      g_assert_cmpint (_i, ==, _start1); \
+      g_assert_cmpint (_end1, <=, _n); \
+    } \
+}G_STMT_END
+
 G_GNUC_UNUSED static char *
 model_to_string (GListModel *model)
 {
@@ -469,6 +486,7 @@ test_model_changes (gconstpointer model_id)
        {
          ensure_updated ();
          assert_model_equal (G_LIST_MODEL (flatten1), G_LIST_MODEL (model2));
+          assert_sections_equal (GTK_SECTION_MODEL (flatten1), GTK_SECTION_MODEL (model2));
        }
    }

--- a/testsuite/gtk/filterlistmodel.c
+++ b/testsuite/gtk/filterlistmodel.c
@@ -323,7 +323,7 @@ test_change_filter (void)
 {
  GtkFilterListModel *filter;
  GtkFilter *custom;
-  
+
  filter = new_model (10, is_not_near, GUINT_TO_POINTER (5));
  assert_model (filter, "1 2 8 9 10");
  assert_changes (filter, "");
@@ -457,6 +457,94 @@ test_add_remove_item (void)
  g_object_unref (filter);
 }

+static int
+sort_func (gconstpointer p1,
+           gconstpointer p2,
+           gpointer      data)
+{
+  const char *s1 = gtk_string_object_get_string ((GtkStringObject *)p1);
+  const char *s2 = gtk_string_object_get_string ((GtkStringObject *)p2);
+
+  /* compare just the first byte */
+  return (int)(s1[0]) - (int)(s2[0]);
+}
+
+static gboolean
+filter_func (gpointer item,
+             gpointer data)
+{
+  const char *s = gtk_string_object_get_string ((GtkStringObject *)item);
+
+  return s[0] == s[1];
+}
+
+static void
+test_sections (void)
+{
+  GtkStringList *list;
+  const char *strings[] = {
+    "aaa",
+    "aab",
+    "abc",
+    "bbb",
+    "bq1",
+    "bq2",
+    "cc",
+    "cx",
+    NULL
+  };
+  GtkSorter *sorter;
+  GtkSortListModel *sorted;
+  GtkSorter *section_sorter;
+  guint s, e;
+  GtkFilterListModel *filtered;
+  GtkFilter *filter;
+
+  list = gtk_string_list_new (strings);
+  sorter = GTK_SORTER (gtk_string_sorter_new (gtk_property_expression_new (GTK_TYPE_STRING_OBJECT, NULL, "string")));
+  sorted = gtk_sort_list_model_new (G_LIST_MODEL (list), sorter);
+  section_sorter = GTK_SORTER (gtk_custom_sorter_new (sort_func, NULL, NULL));
+  gtk_sort_list_model_set_section_sorter (GTK_SORT_LIST_MODEL (sorted), section_sorter);
+  g_object_unref (section_sorter);
+
+  gtk_section_model_get_section (GTK_SECTION_MODEL (sorted), 0, &s, &e);
+  g_assert_cmpint (s, ==, 0);
+  g_assert_cmpint (e, ==, 3);
+  gtk_section_model_get_section (GTK_SECTION_MODEL (sorted), 3, &s, &e);
+  g_assert_cmpint (s, ==, 3);
+  g_assert_cmpint (e, ==, 6);
+  gtk_section_model_get_section (GTK_SECTION_MODEL (sorted), 6, &s, &e);
+  g_assert_cmpint (s, ==, 6);
+  g_assert_cmpint (e, ==, 8);
+
+  filtered = gtk_filter_list_model_new (NULL, NULL);
+  gtk_section_model_get_section (GTK_SECTION_MODEL (filtered), 0, &s, &e);
+  g_assert_cmpint (s, ==, 0);
+  g_assert_cmpint (e, ==, G_MAXUINT);
+
+  gtk_filter_list_model_set_model (filtered, G_LIST_MODEL (sorted));
+  gtk_section_model_get_section (GTK_SECTION_MODEL (filtered), 0, &s, &e);
+  g_assert_cmpint (s, ==, 0);
+  g_assert_cmpint (e, ==, 3);
+
+  filter = GTK_FILTER (gtk_custom_filter_new (filter_func, NULL, NULL));
+  gtk_filter_list_model_set_filter (filtered, filter);
+  g_object_unref (filter);
+
+  gtk_section_model_get_section (GTK_SECTION_MODEL (filtered), 0, &s, &e);
+  g_assert_cmpint (s, ==, 0);
+  g_assert_cmpint (e, ==, 2);
+  gtk_section_model_get_section (GTK_SECTION_MODEL (filtered), 2, &s, &e);
+  g_assert_cmpint (s, ==, 2);
+  g_assert_cmpint (e, ==, 3);
+  gtk_section_model_get_section (GTK_SECTION_MODEL (filtered), 3, &s, &e);
+  g_assert_cmpint (s, ==, 3);
+  g_assert_cmpint (e, ==, 4);
+
+  g_object_unref (filtered);
+  g_object_unref (sorted);
+}
+
 int
 main (int argc, char *argv[])
 {
@@ -472,6 +560,7 @@ main (int argc, char *argv[])
  g_test_add_func ("/filterlistmodel/incremental", test_incremental);
  g_test_add_func ("/filterlistmodel/empty", test_empty);
  g_test_add_func ("/filterlistmodel/add_remove_item", test_add_remove_item);
+  g_test_add_func ("/filterlistmodel/sections", test_sections);

  return g_test_run ();
 }
--- a/testsuite/gtk/listitemmanager.c
+++ b/testsuite/gtk/listitemmanager.c
@@ -0,0 +1,497 @@
+/*
+ * Copyright © 2023 Benjamin Otte
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <locale.h>
+
+#include <gtk/gtk.h>
+#include "gtk/gtklistitemmanagerprivate.h"
+#include "gtk/gtklistbaseprivate.h"
+
+static GListModel *
+create_source_model (guint min_size, guint max_size)
+{
+  GtkStringList *list;
+  guint i, size;
+
+  size = g_test_rand_int_range (min_size, max_size + 1);
+  list = gtk_string_list_new (NULL);
+
+  for (i = 0; i < size; i++)
+    gtk_string_list_append (list, g_test_rand_bit () ? "A" : "B");
+
+  return G_LIST_MODEL (list);
+}
+
+void
+print_list_item_manager_tiles (GtkListItemManager *items)
+{
+  GString *string;
+  GtkListTile *tile;
+
+  string = g_string_new ("");
+
+  for (tile = gtk_list_item_manager_get_first (items);
+       tile != NULL;
+       tile = gtk_rb_tree_node_get_next (tile))
+    {
+      switch (tile->type)
+        {
+          case GTK_LIST_TILE_ITEM:
+            if (tile->widget)
+              g_string_append_c (string, 'W');
+            else if (tile->n_items == 1)
+              g_string_append_c (string, 'x');
+            else
+              g_string_append_printf (string, "%u,", tile->n_items);
+            break;
+          case GTK_LIST_TILE_HEADER:
+            g_string_append_c (string, '[');
+            break;
+          case GTK_LIST_TILE_UNMATCHED_HEADER:
+            g_string_append_c (string, '(');
+            break;
+          case GTK_LIST_TILE_FOOTER:
+            g_string_append_c (string, ']');
+            break;
+          case GTK_LIST_TILE_UNMATCHED_FOOTER:
+            g_string_append_c (string, ')');
+            break;
+
+          case GTK_LIST_TILE_FILLER:
+            g_string_append_c (string, '_');
+            break;
+          case GTK_LIST_TILE_REMOVED:
+            g_string_append_c (string, '.');
+            break;
+          default:
+            g_assert_not_reached ();
+            break;
+        }
+    }
+
+  g_print ("%s\n", string->str);
+
+  g_string_free (string, TRUE);
+}
+
+static void
+check_list_item_manager (GtkListItemManager  *items,
+                         GtkListItemTracker **trackers,
+                         gsize                n_trackers)
+{
+  GListModel *model = G_LIST_MODEL (gtk_list_item_manager_get_model (items));
+  GtkListTile *tile;
+  guint n_items = 0;
+  guint i;
+  gboolean has_sections;
+  enum {
+    NO_SECTION,
+    MATCHED_SECTION,
+    UNMATCHED_SECTION
+  } section_state = NO_SECTION;
+
+  has_sections = gtk_list_item_manager_get_has_sections (items);
+
+  for (tile = gtk_list_item_manager_get_first (items);
+       tile != NULL;
+       tile = gtk_rb_tree_node_get_next (tile))
+    {
+      switch (tile->type)
+        {
+          case GTK_LIST_TILE_HEADER:
+            g_assert_cmpint (section_state, ==, NO_SECTION);
+            g_assert_cmpint (tile->n_items, ==, 0);
+            g_assert_true (has_sections);
+            g_assert_true (tile->widget);
+            section_state = MATCHED_SECTION;
+            break;
+
+          case GTK_LIST_TILE_UNMATCHED_HEADER:
+            g_assert_cmpint (section_state, ==, NO_SECTION);
+            g_assert_cmpint (tile->n_items, ==, 0);
+            g_assert_false (tile->widget);
+            section_state = UNMATCHED_SECTION;
+            break;
+
+          case GTK_LIST_TILE_FOOTER:
+            g_assert_cmpint (section_state, ==, MATCHED_SECTION);
+            g_assert_cmpint (tile->n_items, ==, 0);
+            g_assert_true (has_sections);
+            g_assert_false (tile->widget);
+            section_state = NO_SECTION;
+            break;
+
+          case GTK_LIST_TILE_UNMATCHED_FOOTER:
+            g_assert_cmpint (section_state, ==, UNMATCHED_SECTION);
+            g_assert_cmpint (tile->n_items, ==, 0);
+            g_assert_false (tile->widget);
+            section_state = NO_SECTION;
+            break;
+
+          case GTK_LIST_TILE_ITEM:
+            g_assert_cmpint (section_state, !=, NO_SECTION);
+            if (tile->widget)
+              {
+                GObject *item = g_list_model_get_item (model, n_items);
+                if (has_sections)
+                  g_assert_cmpint (section_state, ==, MATCHED_SECTION);
+                else
+                  g_assert_cmpint (section_state, ==, UNMATCHED_SECTION);
+                g_assert_cmphex (GPOINTER_TO_SIZE (item), ==, GPOINTER_TO_SIZE (gtk_list_item_base_get_item (GTK_LIST_ITEM_BASE (tile->widget))));
+                g_object_unref (item);
+                g_assert_cmpint (n_items, ==, gtk_list_item_base_get_position (GTK_LIST_ITEM_BASE (tile->widget)));
+                g_assert_cmpint (tile->n_items, ==, 1);
+              }
+            if (tile->n_items)
+              n_items += tile->n_items;
+            break;
+
+          case GTK_LIST_TILE_FILLER:
+            /* We don't add fillers */
+            g_assert_not_reached ();
+            break;
+
+          case GTK_LIST_TILE_REMOVED:
+            g_assert_cmpint (tile->n_items, ==, 0);
+            g_assert_false (tile->widget);
+            break;
+
+          default:
+            g_assert_not_reached ();
+            break;
+        }
+    }
+
+  g_assert_cmpint (section_state, ==, NO_SECTION);
+  g_assert_cmpint (n_items, ==, g_list_model_get_n_items (model));
+
+  for (i = 0; i < n_trackers; i++)
+    {
+      guint pos, offset;
+
+      pos = gtk_list_item_tracker_get_position (items, trackers[i]);
+      if (pos == GTK_INVALID_LIST_POSITION)
+        continue;
+      tile = gtk_list_item_manager_get_nth (items, pos, &offset);
+      g_assert_cmpint (tile->n_items, ==, 1);
+      g_assert_cmpint (offset, ==, 0);
+      g_assert_true (tile->widget);
+    }
+
+  for (tile = gtk_list_tile_gc (items, gtk_list_item_manager_get_first (items));
+       tile != NULL;
+       tile = gtk_list_tile_gc (items, gtk_rb_tree_node_get_next (tile)))
+    ;
+
+  n_items = 0;
+
+  for (tile = gtk_list_item_manager_get_first (items);
+       tile != NULL;
+       tile = gtk_rb_tree_node_get_next (tile))
+    {
+      switch (tile->type)
+        {
+          case GTK_LIST_TILE_HEADER:
+            g_assert_cmpint (section_state, ==, NO_SECTION);
+            g_assert_cmpint (tile->n_items, ==, 0);
+            g_assert_true (has_sections);
+            g_assert_true (tile->widget);
+            section_state = MATCHED_SECTION;
+            break;
+
+          case GTK_LIST_TILE_UNMATCHED_HEADER:
+            g_assert_cmpint (section_state, ==, NO_SECTION);
+            g_assert_cmpint (tile->n_items, ==, 0);
+            g_assert_false (tile->widget);
+            section_state = UNMATCHED_SECTION;
+            break;
+
+          case GTK_LIST_TILE_FOOTER:
+            g_assert_cmpint (section_state, ==, MATCHED_SECTION);
+            g_assert_cmpint (tile->n_items, ==, 0);
+            g_assert_true (has_sections);
+            g_assert_false (tile->widget);
+            section_state = NO_SECTION;
+            break;
+
+          case GTK_LIST_TILE_UNMATCHED_FOOTER:
+            g_assert_cmpint (section_state, ==, UNMATCHED_SECTION);
+            g_assert_cmpint (tile->n_items, ==, 0);
+            g_assert_false (tile->widget);
+            section_state = NO_SECTION;
+            break;
+
+          case GTK_LIST_TILE_ITEM:
+            g_assert_cmpint (section_state, !=, NO_SECTION);
+            if (tile->widget)
+              {
+                g_assert_cmpint (tile->n_items, ==, 1);
+              }
+            if (tile->n_items)
+              n_items += tile->n_items;
+            break;
+
+          case GTK_LIST_TILE_FILLER:
+          case GTK_LIST_TILE_REMOVED:
+          default:
+            g_assert_not_reached ();
+            break;
+        }
+    }
+
+  g_assert_cmpint (section_state, ==, NO_SECTION);
+  g_assert_cmpint (n_items, ==, g_list_model_get_n_items (model));
+
+  for (i = 0; i < n_trackers; i++)
+    {
+      guint pos, offset;
+
+      pos = gtk_list_item_tracker_get_position (items, trackers[i]);
+      if (pos == GTK_INVALID_LIST_POSITION)
+        continue;
+      tile = gtk_list_item_manager_get_nth (items, pos, &offset);
+      g_assert_cmpint (tile->n_items, ==, 1);
+      g_assert_cmpint (offset, ==, 0);
+      g_assert_true (tile->widget);
+    }
+}
+
+static GtkListTile *
+split_simple (GtkWidget   *widget,
+              GtkListTile *tile,
+              guint        n_items)
+{
+  GtkListItemManager *items = g_object_get_data (G_OBJECT (widget), "the-items");
+
+  return gtk_list_tile_split (items, tile, n_items);
+}
+
+static void
+prepare_simple (GtkWidget   *widget,
+                GtkListTile *tile,
+                guint        n_items)
+{
+}
+
+static GtkListItemBase *
+create_simple_item (GtkWidget *widget)
+{
+  return g_object_new (GTK_TYPE_LIST_ITEM_BASE, NULL);
+}
+
+static GtkListHeaderBase *
+create_simple_header (GtkWidget *widget)
+{
+  return g_object_new (GTK_TYPE_LIST_HEADER_BASE, NULL);
+}
+
+static void
+test_create (void)
+{
+  GtkListItemManager *items;
+  GtkWidget *widget;
+
+  widget = gtk_window_new ();
+  items = gtk_list_item_manager_new (widget,
+                                     split_simple,
+                                     create_simple_item,
+                                     prepare_simple,
+                                     create_simple_header);
+  g_object_set_data_full (G_OBJECT (widget), "the-items", items, g_object_unref);
+
+  gtk_window_destroy (GTK_WINDOW (widget));
+}
+
+static void
+test_create_with_items (void)
+{
+  GListModel *source;
+  GtkNoSelection *selection;
+  GtkListItemManager *items;
+  GtkWidget *widget;
+
+  widget = gtk_window_new ();
+  items = gtk_list_item_manager_new (widget,
+                                     split_simple,
+                                     create_simple_item,
+                                     prepare_simple,
+                                     create_simple_header);
+  g_object_set_data_full (G_OBJECT (widget), "the-items", items, g_object_unref);
+
+  source = create_source_model (1, 50);
+  selection = gtk_no_selection_new (G_LIST_MODEL (source));
+  gtk_list_item_manager_set_model (items, GTK_SELECTION_MODEL (selection));
+  check_list_item_manager (items, NULL, 0);
+  gtk_list_item_manager_set_model (items, GTK_SELECTION_MODEL (selection));
+  check_list_item_manager (items, NULL, 0);
+
+  g_object_unref (selection);
+  gtk_window_destroy (GTK_WINDOW (widget));
+}
+
+#define N_TRACKERS 3
+#define N_WIDGETS_PER_TRACKER 10
+#define N_RUNS 500
+
+static void
+print_changes_cb (GListModel *model,
+                  guint       position,
+                  guint       removed,
+                  guint       added,
+                  gpointer    unused)
+{
+  if (!g_test_verbose ())
+    return;
+
+  if (removed == 0)
+    g_test_message ("%u/%u: adding %u items", position, g_list_model_get_n_items (model), added);
+  else if (added == 0)
+    g_test_message ("%u/%u: removing %u items", position, g_list_model_get_n_items (model), removed);
+  else
+    g_test_message ("%u/%u: removing %u and adding %u items", position, g_list_model_get_n_items (model), removed, added);
+}
+
+static void
+test_exhaustive (void)
+{
+  GtkListItemTracker *trackers[N_TRACKERS];
+  GListStore *store;
+  GtkFlattenListModel *flatten;
+  GtkNoSelection *selection;
+  GtkListItemManager *items;
+  GtkWidget *widget;
+  gsize i;
+
+  widget = gtk_window_new ();
+  items = gtk_list_item_manager_new (widget,
+                                     split_simple,
+                                     create_simple_item,
+                                     prepare_simple,
+                                     create_simple_header);
+  for (i = 0; i < N_TRACKERS; i++)
+    trackers[i] = gtk_list_item_tracker_new (items);
+
+  g_object_set_data_full (G_OBJECT (widget), "the-items", items, g_object_unref);
+
+  store = g_list_store_new (G_TYPE_OBJECT);
+  flatten = gtk_flatten_list_model_new (G_LIST_MODEL (store));
+  selection = gtk_no_selection_new (G_LIST_MODEL (flatten));
+  g_signal_connect (selection, "items-changed", G_CALLBACK (print_changes_cb), NULL);
+  gtk_list_item_manager_set_model (items, GTK_SELECTION_MODEL (selection));
+
+  for (i = 0; i < N_RUNS; i++)
+    {
+      gboolean add = FALSE, remove = FALSE;
+      guint position, n_items;
+
+      if (g_test_verbose ())
+        print_list_item_manager_tiles (items);
+
+      switch (g_test_rand_int_range (0, 6))
+      {
+        case 0:
+          if (g_test_verbose ())
+            g_test_message ("GC and checking");
+          check_list_item_manager (items, trackers, N_TRACKERS);
+          break;
+
+        case 1:
+          /* remove a model */
+          remove = TRUE;
+          break;
+
+        case 2:
+          /* add a model */
+          add = TRUE;
+          break;
+
+        case 3:
+          /* replace a model */
+          remove = TRUE;
+          add = TRUE;
+          break;
+
+        case 4:
+          n_items = g_list_model_get_n_items (G_LIST_MODEL (selection));
+          if (n_items > 0)
+            {
+              guint tracker_id = g_test_rand_int_range (0, N_TRACKERS);
+              guint pos = g_test_rand_int_range (0, n_items);
+              guint n_before = g_test_rand_int_range (0, N_WIDGETS_PER_TRACKER / 2);
+              guint n_after = g_test_rand_int_range (0, N_WIDGETS_PER_TRACKER / 2);
+              if (g_test_verbose ())
+                g_test_message ("setting tracker %u to %u -%u + %u", tracker_id, pos, n_before, n_after);
+              gtk_list_item_tracker_set_position (items,
+                                                  trackers [tracker_id],
+                                                  pos,
+                                                  n_before, n_after);
+            }
+          break;
+
+        case 5:
+          {
+            gboolean has_sections = g_test_rand_bit ();
+            if (g_test_verbose ())
+              g_test_message ("Setting has_sections to %s", has_sections ? "true" : "false");
+            gtk_list_item_manager_set_has_sections (items, has_sections);
+          }
+          break;
+
+        default:
+          g_assert_not_reached ();
+          break;
+      }
+
+      position = g_test_rand_int_range (0, g_list_model_get_n_items (G_LIST_MODEL (store)) + 1);
+      if (g_list_model_get_n_items (G_LIST_MODEL (store)) == position)
+        remove = FALSE;
+
+      if (add)
+        {
+          /* We want at least one element, otherwise the filters will see no changes */
+          GListModel *source = create_source_model (1, 50);
+          g_list_store_splice (store,
+                               position,
+                               remove ? 1 : 0,
+                               (gpointer *) &source, 1);
+          g_object_unref (source);
+        }
+      else if (remove)
+        {
+          g_list_store_remove (store, position);
+        }
+    }
+
+  check_list_item_manager (items, trackers, N_TRACKERS);
+
+  for (i = 0; i < N_TRACKERS; i++)
+    gtk_list_item_tracker_free (items, trackers[i]);
+  g_object_unref (selection);
+  gtk_window_destroy (GTK_WINDOW (widget));
+}
+
+int
+main (int argc, char *argv[])
+{
+  gtk_test_init (&argc, &argv);
+
+  g_test_add_func ("/listitemmanager/create", test_create);
+  g_test_add_func ("/listitemmanager/create_with_items", test_create_with_items);
+  g_test_add_func ("/listitemmanager/exhaustive", test_exhaustive);
+
+  return g_test_run ();
+}
--- a/testsuite/gtk/meson.build
+++ b/testsuite/gtk/meson.build
@@ -129,6 +129,7 @@ internal_tests = [
  { 'name': 'texthistory' },
  { 'name': 'fnmatch' },
  { 'name': 'a11y' },
+  { 'name': 'listitemmanager' },
 ]

 is_debug = get_option('buildtype').startswith('debug')
--- a/testsuite/gtk/sortlistmodel-exhaustive.c
+++ b/testsuite/gtk/sortlistmodel-exhaustive.c
@@ -36,6 +36,8 @@
      if (o1 != o2) \
        { \
          char *_s = g_strdup_printf ("Objects differ at index %u out of %u", _i, _n); \
+          g_print ("%s\n", model_to_string (model1)); \
+          g_print ("%s\n", model_to_string (model2)); \
         g_assertion_message (G_LOG_DOMAIN, __FILE__, __LINE__, G_STRFUNC, _s); \
          g_free (_s); \
        } \
@@ -45,6 +47,19 @@
    } \
 }G_STMT_END

+#define assert_model_sections(model) G_STMT_START{ \
+  guint _i, _start, _end; \
+  _start = 0; \
+  _end = 0; \
+  for (_i = 0; _i < G_MAXUINT; _i = _end) \
+    { \
+      gtk_section_model_get_section (GTK_SECTION_MODEL (model), _i, &_start, &_end); \
+\
+      g_assert_cmpint (_start, ==, _i); \
+      g_assert_cmpint (_end, >, _i); \
+    } \
+}G_STMT_END
+
 G_GNUC_UNUSED static char *
 model_to_string (GListModel *model)
 {
@@ -287,7 +302,7 @@ create_sorter (gsize id)
      /* match all As, Bs and nothing */
      sorter = GTK_SORTER (gtk_string_sorter_new (gtk_property_expression_new (GTK_TYPE_STRING_OBJECT, NULL, "string")));
      if (id == 1)
-        gtk_string_sorter_set_ignore_case (GTK_STRING_SORTER (sorter), TRUE);
+        gtk_string_sorter_set_ignore_case (GTK_STRING_SORTER (sorter), FALSE);
      return sorter;

    default:
@@ -463,6 +478,258 @@ test_stability (gconstpointer model_id)
  g_object_unref (flatten);
 }

+static gboolean
+string_is_lowercase (GtkStringObject *o)
+{
+  return g_ascii_islower (*gtk_string_object_get_string (o));
+}
+
+/* Run:
+ *   source => section-sorter
+ *   source => sorter
+ * and set a section sorter on the section sorter that is a subsort of
+ * the real sorter.
+ *
+ * And then randomly add/remove sources and change the sorters and
+ * see if the two sorters stay identical
+ */
+static void
+test_section_sorters (gconstpointer model_id)
+{
+  GListStore *store;
+  GtkFlattenListModel *flatten;
+  GtkSortListModel *sort1, *sort2;
+  GtkSorter *sorter;
+  gsize i;
+
+  store = g_list_store_new (G_TYPE_OBJECT);
+  flatten = gtk_flatten_list_model_new (G_LIST_MODEL (store));
+  sort1 = create_sort_list_model (model_id, FALSE, G_LIST_MODEL (flatten), NULL);
+  sort2 = create_sort_list_model (model_id, FALSE, G_LIST_MODEL (flatten), NULL);
+
+  for (i = 0; i < 500; i++)
+    {
+      gboolean add = FALSE, remove = FALSE;
+      guint position;
+
+      switch (g_test_rand_int_range (0, 4))
+      {
+        case 0:
+          /* set the same sorter, once as section sorter, once as sorter */
+          sorter = create_random_sorter (TRUE);
+          gtk_sort_list_model_set_section_sorter (sort1, sorter);
+          gtk_sort_list_model_set_sorter (sort1, NULL);
+          gtk_sort_list_model_set_sorter (sort2, sorter);
+          g_clear_object (&sorter);
+          break;
+
+        case 1:
+          /* use a section sorter that is a more generic version of the sorter */
+          sorter = GTK_SORTER (gtk_string_sorter_new (gtk_property_expression_new (GTK_TYPE_STRING_OBJECT, NULL, "string")));
+          gtk_string_sorter_set_ignore_case (GTK_STRING_SORTER (sorter), FALSE);
+          gtk_sort_list_model_set_sorter (sort1, sorter);
+          gtk_sort_list_model_set_sorter (sort2, sorter);
+          g_clear_object (&sorter);
+          sorter = GTK_SORTER (gtk_numeric_sorter_new (gtk_cclosure_expression_new (G_TYPE_BOOLEAN, NULL, 0, NULL, G_CALLBACK (string_is_lowercase), NULL, NULL)));
+          gtk_sort_list_model_set_section_sorter (sort1, sorter);
+          g_clear_object (&sorter);
+          break;
+
+        case 2:
+          /* remove a model */
+          remove = TRUE;
+          break;
+
+        case 3:
+          /* add a model */
+          add = TRUE;
+          break;
+
+        case 4:
+          /* replace a model */
+          remove = TRUE;
+          add = TRUE;
+          break;
+
+        default:
+          g_assert_not_reached ();
+          break;
+      }
+
+      position = g_test_rand_int_range (0, g_list_model_get_n_items (G_LIST_MODEL (store)) + 1);
+      if (g_list_model_get_n_items (G_LIST_MODEL (store)) == position)
+        remove = FALSE;
+
+      if (add)
+        {
+          /* We want at least one element, otherwise the sorters will see no changes */
+          GListModel *source = create_source_model (1, 50);
+          g_list_store_splice (store,
+                               position,
+                               remove ? 1 : 0,
+                               (gpointer *) &source, 1);
+          g_object_unref (source);
+        }
+      else if (remove)
+        {
+          g_list_store_remove (store, position);
+        }
+
+      if (g_test_rand_bit ())
+        {
+          ensure_updated ();
+          assert_model_equal (G_LIST_MODEL (sort1), G_LIST_MODEL (sort2));
+        }
+
+      if (g_test_rand_bit ())
+        assert_model_sections (G_LIST_MODEL (sort1));
+    }
+
+  g_object_unref (sort2);
+  g_object_unref (sort1);
+  g_object_unref (flatten);
+}
+
+/* Run:
+ *   source => sorter
+ * And then randomly add/remove sources and change the sorters and
+ * see if the invariants for sections keep correct.
+ */
+static void
+test_sections (gconstpointer model_id)
+{
+  GListStore *store;
+  GtkFlattenListModel *flatten;
+  GtkSortListModel *sort;
+  GtkSorter *sorter;
+  gsize i;
+
+  store = g_list_store_new (G_TYPE_OBJECT);
+  flatten = gtk_flatten_list_model_new (G_LIST_MODEL (store));
+  sort = create_sort_list_model (model_id, FALSE, G_LIST_MODEL (flatten), NULL);
+
+  for (i = 0; i < 500; i++)
+    {
+      gboolean add = FALSE, remove = FALSE;
+      guint position;
+
+      switch (g_test_rand_int_range (0, 4))
+      {
+        case 0:
+          /* set the same sorter, once as section sorter, once as sorter */
+          sorter = create_random_sorter (TRUE);
+          gtk_sort_list_model_set_sorter (sort, sorter);
+          g_clear_object (&sorter);
+          break;
+
+        case 1:
+          /* set the same sorter, once as section sorter, once as sorter */
+          sorter = create_random_sorter (TRUE);
+          gtk_sort_list_model_set_section_sorter (sort, sorter);
+          g_clear_object (&sorter);
+          break;
+
+        case 2:
+          /* remove a model */
+          remove = TRUE;
+          break;
+
+        case 3:
+          /* add a model */
+          add = TRUE;
+          break;
+
+        case 4:
+          /* replace a model */
+          remove = TRUE;
+          add = TRUE;
+          break;
+
+        default:
+          g_assert_not_reached ();
+          break;
+      }
+
+      position = g_test_rand_int_range (0, g_list_model_get_n_items (G_LIST_MODEL (store)) + 1);
+      if (g_list_model_get_n_items (G_LIST_MODEL (store)) == position)
+        remove = FALSE;
+
+      if (add)
+        {
+          /* We want at least one element, otherwise the sorters will see no changes */
+          GListModel *source = create_source_model (1, 50);
+          g_list_store_splice (store,
+                               position,
+                               remove ? 1 : 0,
+                               (gpointer *) &source, 1);
+          g_object_unref (source);
+        }
+      else if (remove)
+        {
+          g_list_store_remove (store, position);
+        }
+
+      if (g_test_rand_bit ())
+        ensure_updated ();
+
+      if (g_test_rand_bit ())
+        {
+          guint start, end, pos, n, sec_start, sec_end;
+          gpointer prev_item, item;
+
+          n = g_list_model_get_n_items (G_LIST_MODEL (sort));
+          sorter = gtk_sort_list_model_get_section_sorter (sort);
+          start = end = 0;
+          prev_item = item = NULL;
+
+          for (pos = 0; pos < n; pos++)
+            {
+              gtk_section_model_get_section (GTK_SECTION_MODEL (sort), pos, &sec_start, &sec_end);
+              prev_item = item;
+              item = g_list_model_get_item (G_LIST_MODEL (sort), pos);
+              if (end <= pos)
+                {
+                  g_assert_cmpint (pos, ==, end);
+                  /* there should be a new section */
+                  g_assert_cmpint (sec_start, ==, end);
+                  g_assert_cmpint (sec_end, >, sec_start);
+                  g_assert_cmpint (sec_end, <=, n);
+                  start = sec_start;
+                  end = sec_end;
+                  if (prev_item)
+                    {
+                      g_assert_nonnull (sorter);
+                      g_assert_cmpint (gtk_sorter_compare (sorter, prev_item, item), !=, GTK_ORDERING_EQUAL);
+                    }
+                }
+              else
+                {
+                  /* the old section keeps on going */
+                  g_assert_cmpint (sec_start, ==, start);
+                  g_assert_cmpint (sec_end, ==, end);
+                  if (prev_item && sorter)
+                    g_assert_cmpint (gtk_sorter_compare (sorter, prev_item, item), ==, GTK_ORDERING_EQUAL);
+                }
+              g_clear_object (&prev_item);
+            }
+
+          g_clear_object (&item);
+
+          /* for good measure, check the error condition */
+          if (n < G_MAXINT32)
+            {
+              gtk_section_model_get_section (GTK_SECTION_MODEL (sort), g_test_rand_int_range (n, G_MAXINT32), &sec_start, &sec_end);
+              g_assert_cmpint (sec_start, ==, n);
+              g_assert_cmpint (sec_end, ==, G_MAXUINT);
+            }
+          sorter = NULL;
+        }
+    }
+
+  g_object_unref (sort);
+  g_object_unref (flatten);
+}
+
 static void
 add_test_for_all_models (const char    *name,
                         GTestDataFunc  test_func)
@@ -488,6 +755,8 @@ main (int argc, char *argv[])

  add_test_for_all_models ("two-sorters", test_two_sorters);
  add_test_for_all_models ("stability", test_stability);
+  add_test_for_all_models ("section-sorters", test_section_sorters);
+  add_test_for_all_models ("sections", test_sections);

  return g_test_run ();
 }
--- a/testsuite/gtk/sortlistmodel.c
+++ b/testsuite/gtk/sortlistmodel.c
@@ -258,7 +258,7 @@ test_create (void)
 {
  GtkSortListModel *sort;
  GListStore *store;
-  
+
  store = new_store ((guint[]) { 4, 8, 2, 6, 10, 0 });
  sort = new_model (store);
  assert_model (sort, "2 4 6 8 10");
@@ -280,7 +280,7 @@ test_set_model (void)
 {
  GtkSortListModel *sort;
  GListStore *store;
-  
+
  sort = new_model (NULL);
  assert_model (sort, "");
  assert_changes (sort, "");
@@ -319,7 +319,7 @@ test_set_sorter (void)
  GtkSortListModel *sort;
  GtkSorter *sorter;
  GListStore *store;
-  
+
  store = new_store ((guint[]) { 4, 8, 2, 6, 10, 0 });
  sort = new_model (store);
  assert_model (sort, "2 4 6 8 10");
@@ -350,7 +350,7 @@ test_add_items (void)
 {
  GtkSortListModel *sort;
  GListStore *store;
-  
+
  /* add beginning */
  store = new_store ((guint[]) { 51, 99, 100, 49, 50, 0 });
  sort = new_model (store);
@@ -390,7 +390,7 @@ test_remove_items (void)
 {
  GtkSortListModel *sort;
  GListStore *store;
-  
+
  /* remove beginning */
  store = new_store ((guint[]) { 51, 99, 100, 49, 1, 2, 50, 0 });
  sort = new_model (store);
@@ -570,6 +570,58 @@ test_add_remove_item (void)
  g_object_unref (sort);
 }

+static int
+sort_func (gconstpointer p1,
+           gconstpointer p2,
+           gpointer      data)
+{
+  const char *s1 = gtk_string_object_get_string ((GtkStringObject *)p1);
+  const char *s2 = gtk_string_object_get_string ((GtkStringObject *)p2);
+
+  /* compare just the first byte */
+  return (int)(s1[0]) - (int)(s2[0]);
+}
+
+static void
+test_sections (void)
+{
+  GtkStringList *list;
+  const char *strings[] = {
+    "aaa",
+    "aab",
+    "abc",
+    "bbb",
+    "bq1",
+    "bq2",
+    "cc",
+    "cx",
+    NULL
+  };
+  GtkSorter *sorter;
+  GtkSortListModel *sorted;
+  GtkSorter *section_sorter;
+  guint s, e;
+
+  list = gtk_string_list_new (strings);
+  sorter = GTK_SORTER (gtk_string_sorter_new (gtk_property_expression_new (GTK_TYPE_STRING_OBJECT, NULL, "string")));
+  sorted = gtk_sort_list_model_new (G_LIST_MODEL (list), sorter);
+  section_sorter = GTK_SORTER (gtk_custom_sorter_new (sort_func, NULL, NULL));
+  gtk_sort_list_model_set_section_sorter (GTK_SORT_LIST_MODEL (sorted), section_sorter);
+  g_object_unref (section_sorter);
+
+  gtk_section_model_get_section (GTK_SECTION_MODEL (sorted), 0, &s, &e);
+  g_assert_cmpint (s, ==, 0);
+  g_assert_cmpint (e, ==, 3);
+  gtk_section_model_get_section (GTK_SECTION_MODEL (sorted), 3, &s, &e);
+  g_assert_cmpint (s, ==, 3);
+  g_assert_cmpint (e, ==, 6);
+  gtk_section_model_get_section (GTK_SECTION_MODEL (sorted), 6, &s, &e);
+  g_assert_cmpint (s, ==, 6);
+  g_assert_cmpint (e, ==, 8);
+
+  g_object_unref (sorted);
+}
+
 int
 main (int argc, char *argv[])
 {
@@ -589,6 +641,7 @@ main (int argc, char *argv[])
  g_test_add_func ("/sortlistmodel/incremental/remove", test_incremental_remove);
  g_test_add_func ("/sortlistmodel/oob-access", test_out_of_bounds_access);
  g_test_add_func ("/sortlistmodel/add-remove-item", test_add_remove_item);
+  g_test_add_func ("/sortlistmodel/sections", test_sections);

  return g_test_run ();
 }
Author	SHA1	Message	Date
Matthias Clasen	7bde123457	Typo fix	2023-04-12 16:28:12 +02:00
Matthias Clasen	e45116e69e	Typo fix	2023-04-12 16:26:21 +02:00
Matthias Clasen	7b03bd6d14	Typo fix	2023-04-12 16:26:13 +02:00
Matthias Clasen	169b58b148	gtk-demo: Add columview header demo This does not work yet.	2023-04-12 16:22:37 +02:00
Matthias Clasen	2d16ffe326	columnview: Add a header factory	2023-04-12 15:57:10 +02:00
Benjamin Otte	290eda6243	gtk-demo: Change the settings demo Now it displays a long list of all settings with sections and allows filtering the list to quickly search keys. We might want to keep the old example, too, maybe?	2023-04-12 14:36:50 +02:00
Benjamin Otte	f0335c71b3	theme: Add some random CSS for section headers	2023-04-12 14:36:50 +02:00
Benjamin Otte	2f31fe06a0	listitemmanager: Create header items for sections Now, finally, listitemmanager has all the necessary support to make section headers work.	2023-04-12 14:36:50 +02:00
Benjamin Otte	eb79498f62	listview: GtkListHeader and gtk_list_view_set_header_factory() Adds infrastructure for handling factories for list headers. For now, listitemmanager doesn't instantiate them, so they aren't used.	2023-04-12 14:36:50 +02:00
Benjamin Otte	34106bdda8	listitemmanager: Add GtkListItemChange ... for tracking widgets during changes. This just pulls all the different disjointed parts into one struct with a sensible API.	2023-04-11 15:59:43 +02:00
Benjamin Otte	c474e0ac92	listitemmanager: Add GtkListHeaderBase and vfuncs This is plumbing for section handling. The vfuncs don't do anything, this is just the infrastructure.	2023-04-11 15:59:43 +02:00
Benjamin Otte	c93eaa49b5	listitembase: exit early When update() is called but no values are changed, exit early.	2023-04-11 15:59:43 +02:00
Benjamin Otte	c25d0bbac3	listitemmanager: Make sections configurable Add a gtk_list_item_manager_set_has_sections() (default: FALSE) that requires explicit turning on for the listitemmanager to gain section support.	2023-04-11 15:59:43 +02:00
Benjamin Otte	3353a0836b	listitemmanager: Add/remove sections as needed When ensuring widgets, ensure that their section is known. This will be relevant when we use section widgets. Also ensure that sections that don't cover any widget get destroyed.	2023-04-11 15:59:43 +02:00
Benjamin Otte	29d7c42fee	testsuite: assert widgets are in matched sections All widgets that we display should have their sections known, so assert that that is the case.	2023-04-11 15:59:43 +02:00
Benjamin Otte	176be81ede	testsuite: Add a print function for the listitemmanager This is very useful when debugging.	2023-04-11 15:59:43 +02:00
Benjamin Otte	95effedead	listitemmanager: Add gtk_list_tile_get_next_skip() ... and gtk_list_tile_get_previous_skip() and use them. Allows skipping over REMOVED and FILLER tiles which makes the code a lot more readable.	2023-04-11 15:59:43 +02:00
Benjamin Otte	89cfc182a2	listitemmanager: Add gtk_list_tile_set_type()	2023-04-11 15:59:43 +02:00
Benjamin Otte	c51d82f444	testsuite: Add verbose output to listitemmanager test	2023-04-11 15:59:43 +02:00
Benjamin Otte	cd2c64aff9	listitemmanager: Properly handle sections during add/remove We don't insert sections ourselves yet, but we handle the existing one when items get added or removed.	2023-04-11 15:59:43 +02:00
Benjamin Otte	5f6796b83f	listitemmanager: Augment header/footer info	2023-04-11 15:59:43 +02:00
Benjamin Otte	77f3cd00a9	listitemmanager: Add section tiles For now, we just have a HEADER at the start and a FOOTER at the end. That's hard enough to get right.	2023-04-11 15:59:43 +02:00
Benjamin Otte	a1f41485f8	testsuite: Improve listitemmanager test It now has trackers!	2023-04-11 15:59:43 +02:00
Benjamin Otte	5afda9e732	listitemmanager: Add tile types We have a FILLER and a REMOVED type now. Also makes gc() more sensitive to types.	2023-04-11 15:59:43 +02:00
Benjamin Otte	d181fb11a1	listitemmanager: Add a type to tiles There's only one type for now, but hey, you have to start somewhere.	2023-04-11 15:59:43 +02:00
Benjamin Otte	37340cbebe	testsuite: Add tests for sections to filterlistmodel	2023-04-11 15:59:43 +02:00
Matthias Clasen	38cf1e1895	Add a test for filterlistmodel sections	2023-04-11 15:59:43 +02:00
Matthias Clasen	d93e276f3f	filterlistmodel: Support sections Propagate sections from the child model to the filter model.	2023-04-11 15:59:43 +02:00
Benjamin Otte	778321cb7a	sortlistmodel: add a fast path for get_section()	2023-04-11 15:59:43 +02:00
Benjamin Otte	2259109e32	testsuite: Add section tests to sortlistmodel test	2023-04-11 15:59:43 +02:00
Matthias Clasen	5ceb4c0815	Add a test for sortlistmodel sections	2023-04-11 15:59:43 +02:00
Benjamin Otte	3960098e72	sortlistmodel: Implement GtkSectionModel The get_section() implementation is a slow and steady implementation that has to be careful to not screw up when an incremental sort is only partially sorted.	2023-04-11 15:59:29 +02:00
Benjamin Otte	849df30b50	flattenlistmodel: Implement GtkSectionModel Each child model is reported as one section.	2023-04-11 13:37:32 +02:00
Benjamin Otte	f886f8e677	Implement GtkSectionModel for all selection models	2023-04-11 13:37:32 +02:00
Benjamin Otte	74c55de53d	Add GtkSectionModel Prototyping the interface to be used for sections in listview, so people can review and play with it.	2023-04-11 13:37:32 +02:00
Benjamin Otte	65a631a561	testsuite: Add a listitemmanager test	2023-04-11 13:35:50 +02:00