Merge branch 'selection-filter' into 'master'

Selection filter

See merge request GNOME/gtk!2184

demos/gtk-demo/demo.gresource.xml

@@ -140,6 +140,7 @@
   </gresource>
   <gresource prefix="/listview_colors">
     <file compressed="true">color.names.txt</file>
+    <file>listview_colors.css</file>
   </gresource>
   <gresource prefix="/shortcuts">
     <file>shortcuts.ui</file>

demos/gtk-demo/listview_colors.c

@@ -627,6 +627,23 @@ setup_listitem_cb (GtkListItemFactory *factory,
   gtk_expression_unref (color_expression);
 }
 
+static void
+setup_selection_listitem_cb (GtkListItemFactory *factory,
+                             GtkListItem        *list_item)
+{
+  GtkWidget *picture;
+  GtkExpression *color_expression, *expression;
+
+  expression = gtk_constant_expression_new (GTK_TYPE_LIST_ITEM, list_item);
+  color_expression = gtk_property_expression_new (GTK_TYPE_LIST_ITEM, expression, "item");
+
+  picture = gtk_picture_new ();
+  gtk_widget_set_size_request (picture, 8, 8);
+  gtk_expression_bind (color_expression, picture, "paintable", NULL);
+
+  gtk_list_item_set_child (list_item, picture);
+}
+
 static void
 set_title (gpointer    item,
            const char *title)
@@ -777,6 +794,47 @@ bind_number_item (GtkSignalListItemFactory *factory,
   g_free (string);
 }
 
+static void
+update_selection_count (GListModel *model,
+                        guint       position,
+                        guint       removed,
+                        guint       added,
+                        gpointer    data)
+{
+  char *text;
+  text = g_strdup_printf ("%u", g_list_model_get_n_items (model));
+  gtk_label_set_label (GTK_LABEL (data), text);
+  g_free (text);
+}
+
+static void
+update_selection_average (GListModel *model,
+                          guint       position,
+                          guint       removed,
+                          guint       added,
+                          gpointer    data)
+{
+  guint n = g_list_model_get_n_items (model);
+  GdkRGBA c = { 0, 0, 0, 1 };
+  guint i;
+  GtkColor *color;
+
+  for (i = 0; i < n; i++)
+    {
+      color = g_list_model_get_item (model, i);
+
+      c.red += color->color.red;
+      c.green += color->color.green;
+      c.blue += color->color.blue;
+
+      g_object_unref (color);
+    }
+
+  color = gtk_color_new ("", c.red / n, c.green / n, c.blue / n);
+  gtk_picture_set_paintable (GTK_PICTURE (data), GDK_PAINTABLE (color));
+  g_object_unref (color);
+}
+
 static GtkWidget *window = NULL;
 
 GtkWidget *
@@ -797,6 +855,22 @@ do_listview_colors (GtkWidget *do_widget)
       PangoAttrList *attrs;
       char *string;
       guint len;
+      GtkWidget *selection_view;
+      GListModel *selection_filter;
+      GListModel *no_selection;
+      GtkWidget *grid;
+      GtkWidget *selection_size_label;
+      GtkWidget *selection_average_picture;
+      GtkWidget *selection_info_toggle;
+      GtkWidget *selection_info_revealer;
+      GtkCssProvider *provider;
+
+      provider = gtk_css_provider_new ();
+      gtk_css_provider_load_from_resource (provider, "/listview_colors/listview_colors.css");
+      gtk_style_context_add_provider_for_display (gdk_display_get_default (),
+                                                  GTK_STYLE_PROVIDER (provider),
+                                                  800);
+      g_object_unref (provider);
 
       window = gtk_window_new ();
       gtk_window_set_title (GTK_WINDOW (window), "Colors");
@@ -809,14 +883,85 @@ do_listview_colors (GtkWidget *do_widget)
                               gtk_widget_get_display (do_widget));
       g_object_add_weak_pointer (G_OBJECT (window), (gpointer*)&window);
 
+      box = gtk_box_new (GTK_ORIENTATION_VERTICAL, 0);
+      gtk_window_set_child (GTK_WINDOW (window), box);
+
+      selection_info_revealer = gtk_revealer_new ();
+      gtk_box_append (GTK_BOX (box), selection_info_revealer);
+
+      grid = gtk_grid_new ();
+      gtk_revealer_set_child (GTK_REVEALER (selection_info_revealer), grid);
+      gtk_widget_set_margin_start (grid, 10);
+      gtk_widget_set_margin_end (grid, 10);
+      gtk_widget_set_margin_top (grid, 10);
+      gtk_widget_set_margin_bottom (grid, 10);
+      gtk_grid_set_row_spacing (GTK_GRID (grid), 10);
+      gtk_grid_set_column_spacing (GTK_GRID (grid), 10);
+
+      label = gtk_label_new ("Selection");
+      gtk_widget_set_hexpand (label, TRUE);
+      gtk_widget_add_css_class (label, "title-3");
+      gtk_grid_attach (GTK_GRID (grid), label, 0, 0, 5, 1);
+
+      gtk_grid_attach (GTK_GRID (grid), gtk_label_new ("Size:"), 0, 2, 1, 1);
+
+      selection_size_label = gtk_label_new ("0");
+      gtk_grid_attach (GTK_GRID (grid), selection_size_label, 1, 2, 1, 1);
+
+      gtk_grid_attach (GTK_GRID (grid), gtk_label_new ("Average:"), 2, 2, 1, 1);
+
+      selection_average_picture = gtk_picture_new ();
+      gtk_widget_set_size_request (selection_average_picture, 32, 32);
+      gtk_grid_attach (GTK_GRID (grid), selection_average_picture, 3, 2, 1, 1);
+
+      label = gtk_label_new ("");
+      gtk_widget_set_hexpand (label, TRUE);
+      gtk_grid_attach (GTK_GRID (grid), label, 4, 2, 1, 1);
+
       sw = gtk_scrolled_window_new ();
-      gtk_window_set_child (GTK_WINDOW (window), sw);
+      gtk_widget_set_hexpand (sw, TRUE);
+
+      gtk_grid_attach (GTK_GRID (grid), sw, 0, 1, 5, 1);
+      gtk_scrolled_window_set_policy (GTK_SCROLLED_WINDOW (sw),
+                                      GTK_POLICY_NEVER,
+                                      GTK_POLICY_AUTOMATIC);
+
+      factory = gtk_signal_list_item_factory_new ();
+      g_signal_connect (factory, "setup", G_CALLBACK (setup_selection_listitem_cb), NULL);
+      selection_view = gtk_grid_view_new_with_factory (factory);
+      gtk_widget_add_css_class (selection_view, "compact");
+      gtk_grid_view_set_max_columns (GTK_GRID_VIEW (selection_view), 200);
+      gtk_scrolled_window_set_child (GTK_SCROLLED_WINDOW (sw), selection_view);
+
+      sw = gtk_scrolled_window_new ();
+      gtk_box_append (GTK_BOX (box), sw);
 
       gridview = create_color_grid ();
       gtk_scrolled_window_set_child (GTK_SCROLLED_WINDOW (sw), gridview);
+      gtk_widget_set_hexpand (sw, TRUE);
+      gtk_widget_set_vexpand (sw, TRUE);
       model = gtk_grid_view_get_model (GTK_GRID_VIEW (gridview));
+
+      selection_filter = G_LIST_MODEL (gtk_selection_filter_model_new (GTK_SELECTION_MODEL (model)));
+      g_signal_connect (selection_filter, "items-changed", G_CALLBACK (update_selection_count), selection_size_label);
+      g_signal_connect (selection_filter, "items-changed", G_CALLBACK (update_selection_average), selection_average_picture);
+
+      no_selection = G_LIST_MODEL (gtk_no_selection_new (selection_filter));
+      gtk_grid_view_set_model (GTK_GRID_VIEW (selection_view), no_selection);
+      g_object_unref (selection_filter);
+      g_object_unref (no_selection);
+
       g_object_get (model, "model", &model, NULL);
 
+      selection_info_toggle = gtk_toggle_button_new ();
+      gtk_button_set_icon_name (GTK_BUTTON (selection_info_toggle), "emblem-important-symbolic");
+      gtk_widget_set_tooltip_text (selection_info_toggle, "Show selection info");
+      gtk_header_bar_pack_start (GTK_HEADER_BAR (header), selection_info_toggle);
+
+      g_object_bind_property (selection_info_toggle, "active",
+                              selection_info_revealer, "reveal-child",
+                              G_BINDING_DEFAULT);
+
       button = gtk_button_new_with_mnemonic ("_Refill");
       g_signal_connect (button, "clicked",
                         G_CALLBACK (refill),

demos/gtk-demo/listview_colors.css

@@ -0,0 +1,3 @@
+.view.compact > child {
+  padding: 1px;
+}

docs/reference/gtk/gtk4-docs.xml

@@ -74,6 +74,7 @@
         <xi:include href="xml/gtksingleselection.xml" />
         <xi:include href="xml/gtkmultiselection.xml" />
       </section>
+      <xi:include href="xml/gtkselectionfiltermodel.xml" />
       <xi:include href="xml/gtkbookmarklist.xml" />
       <xi:include href="xml/gtkdirectorylist.xml" />
       <xi:include href="xml/gtkstringlist.xml" />

docs/reference/gtk/gtk4-sections.txt

@@ -355,6 +355,9 @@ gtk_bitset_is_empty
 gtk_bitset_equals
 gtk_bitset_get_minimum
 gtk_bitset_get_maximum
+gtk_bitset_get_size
+gtk_bitset_get_size_in_range
+gtk_bitset_get_nth
 <SUBSECTION>
 gtk_bitset_remove_all
 gtk_bitset_add
@@ -7610,3 +7613,13 @@ gtk_string_list_get_string
 GtkStringObject
 gtk_string_object_get_string
 </SECTION>
+
+<SECTION>
+<FILE>gtkselectionfiltermodel</FILE>
+<TITLE>GtkSelectionFilterModel</TITLE>
+GtkSelectionFilterModel
+gtk_selection_filter_model_new
+gtk_selection_filter_model_new_for_type
+gtk_selection_filter_model_set_model
+gtk_selection_filter_model_get_model
+</SECTION>

docs/reference/gtk/gtk4.types.in

@@ -184,6 +184,7 @@ gtk_scrollbar_get_type
 gtk_scrolled_window_get_type
 gtk_search_bar_get_type
 gtk_search_entry_get_type
+gtk_selection_filter_model_get_type
 gtk_selection_model_get_type
 gtk_separator_get_type
 gtk_settings_get_type

gtk/gtk.h

@@ -213,6 +213,7 @@
 #include <gtk/gtkscrolledwindow.h>
 #include <gtk/gtksearchbar.h>
 #include <gtk/gtksearchentry.h>
+#include <gtk/gtkselectionfiltermodel.h>
 #include <gtk/gtkselectionmodel.h>
 #include <gtk/gtkseparator.h>
 #include <gtk/gtksettings.h>

gtk/gtkbitset.c

@@ -193,6 +193,76 @@ gtk_bitset_get_maximum (const GtkBitset *self)
   return roaring_bitmap_maximum (&self->roaring);
 }
 
+/**
+ * gtk_bitset_get_size:
+ * @self: a #GtkBitSet
+ *
+ * Gets the number of values that were added to the set.  
+ * For example, if the set is empty, 0 is returned.
+ *
+ * Note that this function returns a #guint64, because when all values are
+ * set, the return value is #G_MAXUINT + 1. Unless you are sure this cannot
+ * happen (it can't with #GListModel), be sure to use a 64bit type.
+ *
+ * Returns: The number of values in the set.
+ **/
+guint64
+gtk_bitset_get_size (const GtkBitset *self)
+{
+  g_return_val_if_fail (self != NULL, 0);
+
+  return roaring_bitmap_get_cardinality (&self->roaring);
+}
+
+/**
+ * gtk_bitset_get_size_in_range:
+ * @self: a #GtkBitSet
+ * @first: the first element to include
+ * @last: the last element to include
+ *
+ * Gets the number of values that are part of the set from @first to @last
+ * (inclusive).
+ *
+ * Note that this function returns a #guint64, because when all values are
+ * set, the return value is #G_MAXUINT + 1. Unless you are sure this cannot
+ * happen (it can't with #GListModel), be sure to use a 64bit type.
+ *
+ * Returns: The number of values in the set from @first to @last.
+ **/
+guint64
+gtk_bitset_get_size_in_range (const GtkBitset *self,
+                              guint            first,
+                              guint            last)
+{
+  g_return_val_if_fail (self != NULL, 0);
+  g_return_val_if_fail (last >= first, 0);
+
+  return roaring_bitmap_range_cardinality (&self->roaring, first, ((uint64_t) last) + 1);
+}
+
+/**
+ * gtk_bitset_get_nth:
+ * @self: a #GtkBitset
+ * @nth: index of the item to get
+ *
+ * Returns the value of the @nth item in self.
+ *
+ * If @nth is >= the size of @self, 0 is returned.
+ *
+ * Returns: the value of the @nth item in @self
+ **/
+guint
+gtk_bitset_get_nth (const GtkBitset *self,
+                    guint            nth)
+{
+  uint32_t result;
+
+  if (!roaring_bitmap_select (&self->roaring, nth, &result))
+    return 0;
+
+  return result;
+}
+
 /**
  * gtk_bitset_new_empty:
  *

gtk/gtkbitset.h

@@ -48,6 +48,15 @@ GDK_AVAILABLE_IN_ALL
 gboolean                gtk_bitset_equals                       (const GtkBitset        *self,
                                                                  const GtkBitset        *other);
 GDK_AVAILABLE_IN_ALL
+guint64                 gtk_bitset_get_size                     (const GtkBitset        *self);
+GDK_AVAILABLE_IN_ALL
+guint64                 gtk_bitset_get_size_in_range            (const GtkBitset        *self,
+                                                                 guint                   first,
+                                                                 guint                   last);
+GDK_AVAILABLE_IN_ALL
+guint                   gtk_bitset_get_nth                      (const GtkBitset        *self,
+                                                                 guint                   nth);
+GDK_AVAILABLE_IN_ALL
 guint                   gtk_bitset_get_minimum                  (const GtkBitset        *self);
 GDK_AVAILABLE_IN_ALL
 guint                   gtk_bitset_get_maximum                  (const GtkBitset        *self);

gtk/gtkfilterlistmodel.c

@@ -684,7 +684,7 @@ gtk_filter_list_model_class_init (GtkFilterListModelClass *class)
                            P_("Model"),
                            P_("The model being filtered"),
                            G_TYPE_LIST_MODEL,
-                           GTK_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY | G_PARAM_EXPLICIT_NOTIFY);
+                           GTK_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY);
 
   g_object_class_install_properties (gobject_class, NUM_PROPERTIES, properties);
 }

gtk/gtkselectionfiltermodel.c

@@ -0,0 +1,376 @@
+/*
+ * Copyright © 2020 Red Hat, Inc.
+ *
+ * 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: Matthias Clasen
+ */
+
+#include "config.h"
+
+#include "gtkselectionfiltermodel.h"
+#include "gtkbitset.h"
+
+#include "gtkintl.h"
+#include "gtkprivate.h"
+
+/**
+ * SECTION:gtkselectionfiltermodel
+ * @title: GtkSelectionFilterModel
+ * @short_description: A list model that turns a selection in a model
+ * @see_also: #GtkSelectionModel
+ *
+ * #GtkSelectionFilterModel is a list model that presents the
+ * selected items in a #GtkSelectionModel as its own list model.
+ */
+
+enum {
+  PROP_0,
+  PROP_ITEM_TYPE,
+  PROP_MODEL,
+  NUM_PROPERTIES
+};
+
+struct _GtkSelectionFilterModel
+{
+  GObject parent_instance;
+
+  GType item_type;
+  GtkSelectionModel *model;
+  GtkBitset *selection;
+};
+
+struct _GtkSelectionFilterModelClass
+{
+  GObjectClass parent_class;
+};
+
+static GParamSpec *properties[NUM_PROPERTIES] = { NULL, };
+
+static GType
+gtk_selection_filter_model_get_item_type (GListModel *list)
+{
+  GtkSelectionFilterModel *self = GTK_SELECTION_FILTER_MODEL (list);
+
+  return self->item_type;
+}
+
+static guint
+gtk_selection_filter_model_get_n_items (GListModel *list)
+{
+  GtkSelectionFilterModel *self = GTK_SELECTION_FILTER_MODEL (list);
+
+  if (self->selection)
+    return gtk_bitset_get_size (self->selection);
+
+  return 0;
+}
+
+static gpointer
+gtk_selection_filter_model_get_item (GListModel *list,
+                                     guint       position)
+{
+  GtkSelectionFilterModel *self = GTK_SELECTION_FILTER_MODEL (list);
+
+  position = gtk_bitset_get_nth (self->selection, position);
+
+  return g_list_model_get_item (G_LIST_MODEL (self->model), position);
+}
+
+static void
+gtk_selection_filter_model_list_model_init (GListModelInterface *iface)
+{
+  iface->get_item_type = gtk_selection_filter_model_get_item_type;
+  iface->get_n_items = gtk_selection_filter_model_get_n_items;
+  iface->get_item = gtk_selection_filter_model_get_item;
+}
+
+G_DEFINE_TYPE_WITH_CODE (GtkSelectionFilterModel, gtk_selection_filter_model, G_TYPE_OBJECT,
+                         G_IMPLEMENT_INTERFACE (G_TYPE_LIST_MODEL, gtk_selection_filter_model_list_model_init))
+
+static void
+gtk_selection_filter_model_items_changed_cb (GListModel *model,
+                                             guint       position,
+                                             guint       removed,
+                                             guint       added,
+                                             GtkSelectionFilterModel *self)
+{
+  GtkBitset *selection;
+  guint sel_position;
+  guint sel_removed;
+  guint sel_added;
+
+  selection = gtk_selection_model_get_selection (self->model);
+
+  sel_position = gtk_bitset_get_size_in_range (self->selection, 0, position - 1);
+  sel_removed = gtk_bitset_get_size_in_range (self->selection, position, position + removed);
+  sel_added = gtk_bitset_get_size_in_range (selection, position, position + added);
+
+  gtk_bitset_unref (self->selection);
+  self->selection = gtk_bitset_copy (selection);
+
+  gtk_bitset_unref (selection);
+
+  if (sel_removed > 0 || sel_added > 0)
+    g_list_model_items_changed (G_LIST_MODEL (self), sel_position, sel_removed, sel_added);
+}
+
+static void
+gtk_selection_filter_model_selection_changed_cb (GListModel *model,
+                                                 guint       position,
+                                                 guint       n_items,
+                                                 GtkSelectionFilterModel *self)
+{
+  GtkBitset *selection;
+  guint sel_position;
+  guint sel_removed;
+  guint sel_added;
+
+  selection = gtk_selection_model_get_selection (self->model);
+
+  sel_position = gtk_bitset_get_size_in_range (self->selection, 0, position - 1);
+  sel_removed = gtk_bitset_get_size_in_range (self->selection, position, position + n_items);
+  sel_added = gtk_bitset_get_size_in_range (selection, position, position + n_items);
+
+  gtk_bitset_unref (self->selection);
+  self->selection = gtk_bitset_copy (selection);
+
+  gtk_bitset_unref (selection);
+
+  if (sel_removed > 0 || sel_added > 0)
+    g_list_model_items_changed (G_LIST_MODEL (self), sel_position, sel_removed, sel_added);
+}
+
+static void
+gtk_selection_filter_model_set_property (GObject      *object,
+                                         guint         prop_id,
+                                         const GValue *value,
+                                         GParamSpec   *pspec)
+{
+  GtkSelectionFilterModel *self = GTK_SELECTION_FILTER_MODEL (object);
+
+  switch (prop_id)
+    {
+    case PROP_ITEM_TYPE:
+      self->item_type = g_value_get_gtype (value);
+      break;
+
+    case PROP_MODEL:
+      gtk_selection_filter_model_set_model (self, g_value_get_object (value));
+      break;
+
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+    }
+}
+
+static void
+gtk_selection_filter_model_get_property (GObject     *object,
+                                         guint        prop_id,
+                                         GValue      *value,
+                                         GParamSpec  *pspec)
+{
+  GtkSelectionFilterModel *self = GTK_SELECTION_FILTER_MODEL (object);
+
+  switch (prop_id)
+    {
+    case PROP_ITEM_TYPE:
+      g_value_set_gtype (value, self->item_type);
+      break;
+
+    case PROP_MODEL:
+      g_value_set_object (value, self->model);
+      break;
+
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+    }
+}
+
+static void
+gtk_selection_filter_model_clear_model (GtkSelectionFilterModel *self)
+{
+  if (self->model == NULL)
+    return;
+
+  g_signal_handlers_disconnect_by_func (self->model, gtk_selection_filter_model_items_changed_cb, self);
+  g_signal_handlers_disconnect_by_func (self->model, gtk_selection_filter_model_selection_changed_cb, self);
+
+  g_clear_object (&self->model);
+  g_clear_pointer (&self->selection, gtk_bitset_unref);
+}
+
+static void
+gtk_selection_filter_model_dispose (GObject *object)
+{
+  GtkSelectionFilterModel *self = GTK_SELECTION_FILTER_MODEL (object);
+
+  gtk_selection_filter_model_clear_model (self);
+
+  G_OBJECT_CLASS (gtk_selection_filter_model_parent_class)->dispose (object);
+}
+
+static void
+gtk_selection_filter_model_class_init (GtkSelectionFilterModelClass *class)
+{
+  GObjectClass *gobject_class = G_OBJECT_CLASS (class);
+
+  gobject_class->set_property = gtk_selection_filter_model_set_property;
+  gobject_class->get_property = gtk_selection_filter_model_get_property;
+  gobject_class->dispose = gtk_selection_filter_model_dispose;
+
+  /**
+   * GtkSelectionFilterModel:item-type:
+   *
+   * The #GType for elements of this object
+   */
+  properties[PROP_ITEM_TYPE] =
+      g_param_spec_gtype ("item-type",
+                          P_("Item type"),
+                          P_("The type of elements of this object"),
+                          G_TYPE_OBJECT,
+                          GTK_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY | G_PARAM_EXPLICIT_NOTIFY);
+
+  /**
+   * GtkSelectionFilterModel:model:
+   *
+   * The model being filtered
+   */
+  properties[PROP_MODEL] =
+      g_param_spec_object ("model",
+                           P_("Model"),
+                           P_("The model being filtered"),
+                           GTK_TYPE_SELECTION_MODEL,
+                           GTK_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY);
+
+  g_object_class_install_properties (gobject_class, NUM_PROPERTIES, properties);
+}
+
+static void
+gtk_selection_filter_model_init (GtkSelectionFilterModel *self)
+{
+}
+
+/**
+ * gtk_selection_filter_model_new:
+ * @model: the selection model to filter
+ *
+ * Creates a new #GtkSelectionFilterModel that will include the
+ * selected items from the underlying selection model.
+ *
+ * Returns: a new #GtkSelectionFilterModel
+ **/
+GtkSelectionFilterModel *
+gtk_selection_filter_model_new (GtkSelectionModel *model)
+{
+  GtkSelectionFilterModel *result;
+
+  g_return_val_if_fail (GTK_IS_SELECTION_MODEL (model), NULL);
+
+  result = g_object_new (GTK_TYPE_SELECTION_FILTER_MODEL,
+                         "item-type", g_list_model_get_item_type (G_LIST_MODEL (model)),
+                         "model", model,
+                         NULL);
+
+  return result;
+}
+
+/**
+ * gtk_selection_filter_model_new_for_type:
+ * @item_type: the type of the items that will be returned
+ *
+ * Creates a new empty selection filter model set up to return items
+ * of type @item_type. It is up to the application to set a proper
+ * selection model to ensure the item type is matched.
+ *
+ * Returns: a new #GtkSelectionFilterModel
+ **/
+GtkSelectionFilterModel *
+gtk_selection_filter_model_new_for_type (GType item_type)
+{
+  g_return_val_if_fail (g_type_is_a (item_type, G_TYPE_OBJECT), NULL);
+
+  return g_object_new (GTK_TYPE_SELECTION_FILTER_MODEL,
+                       "item-type", item_type,
+                       NULL);
+}
+
+/**
+ * gtk_selection_filter_model_set_model:
+ * @self: a #GtkSelectionFilterModel
+ * @model: (allow-none): The model to be filtered
+ *
+ * Sets the model to be filtered.
+ *
+ * Note that GTK makes no effort to ensure that @model conforms to
+ * the item type of @self. It assumes that the caller knows what they
+ * are doing and have set up an appropriate filter to ensure that item
+ * types match.
+ **/
+void
+gtk_selection_filter_model_set_model (GtkSelectionFilterModel *self,
+                                      GtkSelectionModel       *model)
+{
+  guint removed, added;
+
+  g_return_if_fail (GTK_IS_SELECTION_FILTER_MODEL (self));
+  g_return_if_fail (model == NULL || GTK_IS_SELECTION_MODEL (model));
+  g_return_if_fail (model == NULL || g_type_is_a (g_list_model_get_item_type (G_LIST_MODEL (model)),
+                                                  self->item_type));
+
+  if (self->model == model)
+    return;
+
+  removed = g_list_model_get_n_items (G_LIST_MODEL (self));
+  gtk_selection_filter_model_clear_model (self);
+
+  if (model)
+    {
+      GtkBitset *selection;
+
+      self->model = g_object_ref (model);
+
+      selection = gtk_selection_model_get_selection (self->model);
+      self->selection = gtk_bitset_copy (selection);
+      gtk_bitset_unref (selection);
+
+      g_signal_connect (model, "items-changed", G_CALLBACK (gtk_selection_filter_model_items_changed_cb), self);
+      g_signal_connect (model, "selection-changed", G_CALLBACK (gtk_selection_filter_model_selection_changed_cb), self);
+    }
+
+  added = g_list_model_get_n_items (G_LIST_MODEL (self));
+
+  if (removed > 0 || added > 0)
+    g_list_model_items_changed (G_LIST_MODEL (self), 0, removed, added);
+
+  g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_MODEL]);
+}
+
+/**
+ * gtk_selection_filter_model_get_model:
+ * @self: a #GtkSelectionFilterModel
+ *
+ * Gets the model currently filtered or %NULL if none.
+ *
+ * Returns: (nullable) (transfer none): The model that gets filtered
+ **/
+GtkSelectionModel *
+gtk_selection_filter_model_get_model (GtkSelectionFilterModel *self)
+{
+  g_return_val_if_fail (GTK_IS_SELECTION_FILTER_MODEL (self), NULL);
+
+  return self->model;
+}

gtk/gtkselectionfiltermodel.h

@@ -0,0 +1,52 @@
+/*
+ * Copyright © 2020 Red Hat, Inc.
+ *
+ * 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: Matthias Clasen
+ */
+
+#ifndef __GTK_SELECTION_FILTER_MODEL_H__
+#define __GTK_SELECTION_FILTER_MODEL_H__
+
+
+#if !defined (__GTK_H_INSIDE__) && !defined (GTK_COMPILATION)
+#error "Only <gtk/gtk.h> can be included directly."
+#endif
+
+#include <gio/gio.h>
+#include <gtk/gtkselectionmodel.h>
+
+G_BEGIN_DECLS
+
+#define GTK_TYPE_SELECTION_FILTER_MODEL (gtk_selection_filter_model_get_type ())
+
+GDK_AVAILABLE_IN_ALL
+G_DECLARE_FINAL_TYPE (GtkSelectionFilterModel, gtk_selection_filter_model, GTK, SELECTION_FILTER_MODEL, GObject)
+
+GDK_AVAILABLE_IN_ALL
+GtkSelectionFilterModel * gtk_selection_filter_model_new          (GtkSelectionModel           *model);
+
+GDK_AVAILABLE_IN_ALL
+GtkSelectionFilterModel * gtk_selection_filter_model_new_for_type (GType                        item_type);
+
+GDK_AVAILABLE_IN_ALL
+void                      gtk_selection_filter_model_set_model    (GtkSelectionFilterModel     *self,
+                                                                   GtkSelectionModel           *model);
+GDK_AVAILABLE_IN_ALL
+GtkSelectionModel *       gtk_selection_filter_model_get_model    (GtkSelectionFilterModel     *self);
+
+G_END_DECLS
+
+#endif /* __GTK_SELECTION_FILTER_MODEL_H__ */

gtk/meson.build

@@ -348,6 +348,7 @@ gtk_public_sources = files([
   'gtkscrolledwindow.c',
   'gtksearchbar.c',
   'gtksearchentry.c',
+  'gtkselectionfiltermodel.c',
   'gtkselectionmodel.c',
   'gtkseparator.c',
   'gtksettings.c',
@@ -617,6 +618,7 @@ gtk_public_headers = files([
   'gtkscrolledwindow.h',
   'gtksearchbar.h',
   'gtksearchentry.h',
+  'gtkselectionfiltermodel.h',
   'gtkselectionmodel.h',
   'gtkseparator.h',
   'gtksettings.h',