[pango/listmodel-properties: 6/7] Add listmodel properties to PangoFontMap

[Matthias Clasen <matthiasc src gnome org>]

commit 99eef5994c361eb9f09066aac4b6660f3c5518c1
Author: Matthias Clasen <mclasen redhat com>
Date:   Fri Jun 10 07:17:52 2022 -0400

    Add listmodel properties to PangoFontMap
    
    Add :item-type and :n-items properties, which
    make the list model implementation more useful.

 pango/pango-fontmap.c | 59 +++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 59 insertions(+)
---
diff --git a/pango/pango-fontmap.c b/pango/pango-fontmap.c
index 71e3e20c..20ecb93e 100644
--- a/pango/pango-fontmap.c
+++ b/pango/pango-fontmap.c
@@ -39,22 +39,79 @@ static PangoFontFamily *pango_font_map_real_get_family (PangoFontMap *fontmap,
 
 static void pango_font_map_real_changed (PangoFontMap *fontmap);
 
+static guint pango_font_map_get_n_items (GListModel *list);
+
 static void pango_font_map_list_model_init (GListModelInterface *iface);
 
 typedef struct {
   guint n_families;
 } PangoFontMapPrivate;
 
+enum
+{
+  PROP_0,
+  PROP_ITEM_TYPE,
+  PROP_N_ITEMS,
+  N_PROPERTIES
+};
+
+static GParamSpec *properties[N_PROPERTIES] = { NULL, };
+
 G_DEFINE_ABSTRACT_TYPE_WITH_CODE (PangoFontMap, pango_font_map, G_TYPE_OBJECT,
                                   G_ADD_PRIVATE (PangoFontMap)
                                   G_IMPLEMENT_INTERFACE (G_TYPE_LIST_MODEL, pango_font_map_list_model_init))
 
+static void
+pango_font_map_get_property (GObject    *object,
+                             guint       property_id,
+                             GValue     *value,
+                             GParamSpec *pspec)
+{
+  switch (property_id)
+    {
+    case PROP_ITEM_TYPE:
+      g_value_set_gtype (value, PANGO_TYPE_FONT_FAMILY);
+      break;
+
+    case PROP_N_ITEMS:
+      g_value_set_uint (value, pango_font_map_get_n_items (G_LIST_MODEL (object)));
+      break;
+
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
+    }
+}
+
 static void
 pango_font_map_class_init (PangoFontMapClass *class)
 {
+  GObjectClass *object_class = G_OBJECT_CLASS (class);
+
+  object_class->get_property = pango_font_map_get_property;
+
   class->load_fontset = pango_font_map_real_load_fontset;
   class->get_family = pango_font_map_real_get_family;
   class->changed = pango_font_map_real_changed;
+
+  /**
+   * PangoFontMap:item-type:
+   *
+   * The type of items contained in this list.
+   */
+  properties[PROP_ITEM_TYPE] =
+    g_param_spec_gtype ("item-type", "", "", G_TYPE_OBJECT,
+                        G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);
+
+  /**
+   * PangoFontMap:n-items:
+   *
+   * The number of items contained in this list.
+   */
+  properties[PROP_N_ITEMS] =
+    g_param_spec_uint ("n-items", "", "", 0, G_MAXUINT, 0,
+                       G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);
+
+  g_object_class_install_properties (object_class, N_PROPERTIES, properties);
 }
 
 static void
@@ -355,6 +412,8 @@ pango_font_map_real_changed (PangoFontMap *fontmap)
   added = g_list_model_get_n_items (G_LIST_MODEL (fontmap));
 
   g_list_model_items_changed (G_LIST_MODEL (fontmap), 0, removed, added);
+  if (removed != added)
+    g_object_notify_by_pspec (G_OBJECT (fontmap), properties[PROP_N_ITEMS]);
 }
 
 /**