summaryrefslogtreecommitdiffstats
path: root/src/st/st-icon.c
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--src/st/st-icon.c791
1 files changed, 791 insertions, 0 deletions
diff --git a/src/st/st-icon.c b/src/st/st-icon.c
new file mode 100644
index 0000000..c9d7a85
--- /dev/null
+++ b/src/st/st-icon.c
@@ -0,0 +1,791 @@
+/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
+/*
+ * st-icon.c: icon widget
+ *
+ * Copyright 2009, 2010 Intel Corporation.
+ * Copyright 2010 Red Hat, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU Lesser General Public License,
+ * version 2.1, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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 program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/**
+ * SECTION:st-icon
+ * @short_description: a simple styled icon actor
+ *
+ * #StIcon is a simple styled texture actor that displays an image from
+ * a stylesheet.
+ */
+
+#include "st-enum-types.h"
+#include "st-icon.h"
+#include "st-texture-cache.h"
+#include "st-theme-context.h"
+#include "st-private.h"
+
+enum
+{
+ PROP_0,
+
+ PROP_GICON,
+ PROP_FALLBACK_GICON,
+
+ PROP_ICON_NAME,
+ PROP_ICON_SIZE,
+ PROP_FALLBACK_ICON_NAME,
+
+ N_PROPS
+};
+
+static GParamSpec *props[N_PROPS] = { NULL, };
+
+struct _StIconPrivate
+{
+ ClutterActor *icon_texture;
+ ClutterActor *pending_texture;
+ gulong opacity_handler_id;
+
+ GIcon *gicon;
+ gint prop_icon_size; /* icon size set as property */
+ gint theme_icon_size; /* icon size from theme node */
+ gint icon_size; /* icon size we are using */
+ GIcon *fallback_gicon;
+
+ CoglPipeline *shadow_pipeline;
+ StShadow *shadow_spec;
+ graphene_size_t shadow_size;
+};
+
+G_DEFINE_TYPE_WITH_PRIVATE (StIcon, st_icon, ST_TYPE_WIDGET)
+
+static void st_icon_update (StIcon *icon);
+static gboolean st_icon_update_icon_size (StIcon *icon);
+static void st_icon_update_shadow_pipeline (StIcon *icon);
+static void st_icon_clear_shadow_pipeline (StIcon *icon);
+
+static GIcon *default_gicon = NULL;
+
+#define IMAGE_MISSING_ICON_NAME "image-missing"
+#define DEFAULT_ICON_SIZE 48
+
+static void
+st_icon_set_property (GObject *gobject,
+ guint prop_id,
+ const GValue *value,
+ GParamSpec *pspec)
+{
+ StIcon *icon = ST_ICON (gobject);
+
+ switch (prop_id)
+ {
+ case PROP_GICON:
+ st_icon_set_gicon (icon, g_value_get_object (value));
+ break;
+
+ case PROP_FALLBACK_GICON:
+ st_icon_set_fallback_gicon (icon, g_value_get_object (value));
+ break;
+
+ case PROP_ICON_NAME:
+ st_icon_set_icon_name (icon, g_value_get_string (value));
+ break;
+
+ case PROP_ICON_SIZE:
+ st_icon_set_icon_size (icon, g_value_get_int (value));
+ break;
+
+ case PROP_FALLBACK_ICON_NAME:
+ st_icon_set_fallback_icon_name (icon, g_value_get_string (value));
+ break;
+
+ default:
+ G_OBJECT_WARN_INVALID_PROPERTY_ID (gobject, prop_id, pspec);
+ break;
+ }
+}
+
+static void
+st_icon_get_property (GObject *gobject,
+ guint prop_id,
+ GValue *value,
+ GParamSpec *pspec)
+{
+ StIcon *icon = ST_ICON (gobject);
+
+ switch (prop_id)
+ {
+ case PROP_GICON:
+ g_value_set_object (value, st_icon_get_gicon (icon));
+ break;
+
+ case PROP_FALLBACK_GICON:
+ g_value_set_object (value, st_icon_get_fallback_gicon (icon));
+ break;
+
+ case PROP_ICON_NAME:
+ g_value_set_string (value, st_icon_get_icon_name (icon));
+ break;
+
+ case PROP_ICON_SIZE:
+ g_value_set_int (value, st_icon_get_icon_size (icon));
+ break;
+
+ case PROP_FALLBACK_ICON_NAME:
+ g_value_set_string (value, st_icon_get_fallback_icon_name (icon));
+ break;
+
+ default:
+ G_OBJECT_WARN_INVALID_PROPERTY_ID (gobject, prop_id, pspec);
+ break;
+ }
+}
+
+static void
+st_icon_dispose (GObject *gobject)
+{
+ StIconPrivate *priv = ST_ICON (gobject)->priv;
+
+ if (priv->icon_texture)
+ {
+ clutter_actor_destroy (priv->icon_texture);
+ priv->icon_texture = NULL;
+ }
+
+ if (priv->pending_texture)
+ {
+ clutter_actor_destroy (priv->pending_texture);
+ g_object_unref (priv->pending_texture);
+ priv->pending_texture = NULL;
+ }
+
+ g_clear_object (&priv->gicon);
+ g_clear_object (&priv->fallback_gicon);
+ g_clear_pointer (&priv->shadow_pipeline, cogl_object_unref);
+ g_clear_pointer (&priv->shadow_spec, st_shadow_unref);
+
+ G_OBJECT_CLASS (st_icon_parent_class)->dispose (gobject);
+}
+
+static void
+st_icon_paint (ClutterActor *actor,
+ ClutterPaintContext *paint_context)
+{
+ StIcon *icon = ST_ICON (actor);
+ StIconPrivate *priv = icon->priv;
+
+ st_widget_paint_background (ST_WIDGET (actor), paint_context);
+
+ if (priv->icon_texture)
+ {
+ st_icon_update_shadow_pipeline (icon);
+
+ if (priv->shadow_pipeline)
+ {
+ ClutterActorBox allocation;
+ CoglFramebuffer *framebuffer;
+
+ clutter_actor_get_allocation_box (priv->icon_texture, &allocation);
+ framebuffer = clutter_paint_context_get_framebuffer (paint_context);
+ _st_paint_shadow_with_opacity (priv->shadow_spec,
+ framebuffer,
+ priv->shadow_pipeline,
+ &allocation,
+ clutter_actor_get_paint_opacity (priv->icon_texture));
+ }
+
+ clutter_actor_paint (priv->icon_texture, paint_context);
+ }
+}
+
+static void
+st_icon_style_changed (StWidget *widget)
+{
+ StIcon *self = ST_ICON (widget);
+ StThemeNode *theme_node = st_widget_get_theme_node (widget);
+ StIconPrivate *priv = self->priv;
+
+ st_icon_clear_shadow_pipeline (self);
+ g_clear_pointer (&priv->shadow_spec, st_shadow_unref);
+
+ priv->shadow_spec = st_theme_node_get_shadow (theme_node, "icon-shadow");
+
+ if (priv->shadow_spec && priv->shadow_spec->inset)
+ {
+ g_warning ("The icon-shadow property does not support inset shadows");
+ st_shadow_unref (priv->shadow_spec);
+ priv->shadow_spec = NULL;
+ }
+
+ priv->theme_icon_size = (int)(0.5 + st_theme_node_get_length (theme_node, "icon-size"));
+ st_icon_update_icon_size (self);
+ st_icon_update (self);
+}
+
+static void
+st_icon_resource_scale_changed (ClutterActor *actor)
+{
+ st_icon_update (ST_ICON (actor));
+
+ if (CLUTTER_ACTOR_CLASS (st_icon_parent_class)->resource_scale_changed)
+ CLUTTER_ACTOR_CLASS (st_icon_parent_class)->resource_scale_changed (actor);
+}
+
+static void
+st_icon_class_init (StIconClass *klass)
+{
+ GObjectClass *object_class = G_OBJECT_CLASS (klass);
+ ClutterActorClass *actor_class = CLUTTER_ACTOR_CLASS (klass);
+ StWidgetClass *widget_class = ST_WIDGET_CLASS (klass);
+
+ object_class->get_property = st_icon_get_property;
+ object_class->set_property = st_icon_set_property;
+ object_class->dispose = st_icon_dispose;
+
+ actor_class->paint = st_icon_paint;
+
+ widget_class->style_changed = st_icon_style_changed;
+ actor_class->resource_scale_changed = st_icon_resource_scale_changed;
+
+ /**
+ * StIcon:gicon:
+ *
+ * The #GIcon being displayed by this #StIcon.
+ */
+ props[PROP_GICON] =
+ g_param_spec_object ("gicon",
+ "GIcon",
+ "The GIcon shown by this icon actor",
+ G_TYPE_ICON,
+ ST_PARAM_READWRITE);
+
+ /**
+ * StIcon:fallback-gicon:
+ *
+ * The fallback #GIcon to display if #StIcon:gicon fails to load.
+ */
+ props[PROP_FALLBACK_GICON] =
+ g_param_spec_object ("fallback-gicon",
+ "Fallback GIcon",
+ "The fallback GIcon shown if the normal icon fails to load",
+ G_TYPE_ICON,
+ ST_PARAM_READWRITE);
+
+ /**
+ * StIcon:icon-name:
+ *
+ * The name of the icon if the icon being displayed is a #GThemedIcon.
+ */
+ props[PROP_ICON_NAME] =
+ g_param_spec_string ("icon-name",
+ "Icon name",
+ "An icon name",
+ NULL,
+ ST_PARAM_READWRITE);
+
+ /**
+ * StIcon:icon-size:
+ *
+ * The size of the icon, if greater than `0`. Other the icon size is derived
+ * from the current style.
+ */
+ props[PROP_ICON_SIZE] =
+ g_param_spec_int ("icon-size",
+ "Icon size",
+ "The size if the icon, if positive. Otherwise the size will be derived from the current style",
+ -1, G_MAXINT, -1,
+ ST_PARAM_READWRITE);
+
+ /**
+ * StIcon:fallback-icon-name:
+ *
+ * The fallback icon name of the #StIcon. See st_icon_set_fallback_icon_name()
+ * for details.
+ */
+ props[PROP_FALLBACK_ICON_NAME] =
+ g_param_spec_string ("fallback-icon-name",
+ "Fallback icon name",
+ "A fallback icon name",
+ NULL,
+ ST_PARAM_READWRITE);
+
+ g_object_class_install_properties (object_class, N_PROPS, props);
+}
+
+static void
+st_icon_init (StIcon *self)
+{
+ ClutterLayoutManager *layout_manager;
+
+ if (G_UNLIKELY (default_gicon == NULL))
+ default_gicon = g_themed_icon_new (IMAGE_MISSING_ICON_NAME);
+
+ self->priv = st_icon_get_instance_private (self);
+
+ layout_manager = clutter_bin_layout_new (CLUTTER_BIN_ALIGNMENT_FILL,
+ CLUTTER_BIN_ALIGNMENT_FILL);
+ clutter_actor_set_layout_manager (CLUTTER_ACTOR (self), layout_manager);
+
+ self->priv->icon_size = DEFAULT_ICON_SIZE;
+ self->priv->prop_icon_size = -1;
+
+ self->priv->shadow_pipeline = NULL;
+}
+
+static void
+st_icon_clear_shadow_pipeline (StIcon *icon)
+{
+ StIconPrivate *priv = icon->priv;
+
+ g_clear_pointer (&priv->shadow_pipeline, cogl_object_unref);
+ graphene_size_init (&priv->shadow_size, 0, 0);
+}
+
+static void
+st_icon_update_shadow_pipeline (StIcon *icon)
+{
+ StIconPrivate *priv = icon->priv;
+
+ if (priv->icon_texture && priv->shadow_spec)
+ {
+ ClutterActorBox box;
+ float width, height;
+
+ clutter_actor_get_allocation_box (CLUTTER_ACTOR (icon), &box);
+ clutter_actor_box_get_size (&box, &width, &height);
+
+ if (priv->shadow_pipeline == NULL ||
+ priv->shadow_size.width != width ||
+ priv->shadow_size.height != height)
+ {
+ st_icon_clear_shadow_pipeline (icon);
+
+ priv->shadow_pipeline =
+ _st_create_shadow_pipeline_from_actor (priv->shadow_spec,
+ priv->icon_texture);
+
+ if (priv->shadow_pipeline)
+ graphene_size_init (&priv->shadow_size, width, height);
+ }
+ }
+}
+
+static void
+on_content_changed (ClutterActor *actor,
+ GParamSpec *pspec,
+ StIcon *icon)
+{
+ st_icon_clear_shadow_pipeline (icon);
+}
+
+static void
+st_icon_finish_update (StIcon *icon)
+{
+ StIconPrivate *priv = icon->priv;
+
+ if (priv->icon_texture)
+ {
+ clutter_actor_destroy (priv->icon_texture);
+ priv->icon_texture = NULL;
+ }
+
+ if (priv->pending_texture)
+ {
+ priv->icon_texture = priv->pending_texture;
+ priv->pending_texture = NULL;
+ clutter_actor_set_x_align (priv->icon_texture, CLUTTER_ACTOR_ALIGN_CENTER);
+ clutter_actor_set_y_align (priv->icon_texture, CLUTTER_ACTOR_ALIGN_CENTER);
+ clutter_actor_add_child (CLUTTER_ACTOR (icon), priv->icon_texture);
+
+ /* Remove the temporary ref we added */
+ g_object_unref (priv->icon_texture);
+
+ st_icon_clear_shadow_pipeline (icon);
+
+ g_signal_connect_object (priv->icon_texture, "notify::content",
+ G_CALLBACK (on_content_changed), icon, 0);
+ }
+
+ clutter_actor_queue_relayout (CLUTTER_ACTOR (icon));
+}
+
+static void
+opacity_changed_cb (GObject *object,
+ GParamSpec *pspec,
+ gpointer user_data)
+{
+ StIcon *icon = user_data;
+ StIconPrivate *priv = icon->priv;
+
+ g_clear_signal_handler (&priv->opacity_handler_id, priv->pending_texture);
+
+ st_icon_finish_update (icon);
+}
+
+static void
+st_icon_update (StIcon *icon)
+{
+ StIconPrivate *priv = icon->priv;
+ StThemeNode *theme_node;
+ StTextureCache *cache;
+ gint paint_scale;
+ ClutterActor *stage;
+ StThemeContext *context;
+ float resource_scale;
+
+ if (priv->pending_texture)
+ {
+ clutter_actor_destroy (priv->pending_texture);
+ g_object_unref (priv->pending_texture);
+ priv->pending_texture = NULL;
+ priv->opacity_handler_id = 0;
+ }
+
+ if (priv->gicon == NULL && priv->fallback_gicon == NULL)
+ {
+ g_clear_pointer (&priv->icon_texture, clutter_actor_destroy);
+ return;
+ }
+
+ resource_scale = clutter_actor_get_resource_scale (CLUTTER_ACTOR (icon));
+
+ theme_node = st_widget_peek_theme_node (ST_WIDGET (icon));
+ if (theme_node == NULL)
+ return;
+
+ stage = clutter_actor_get_stage (CLUTTER_ACTOR (icon));
+ context = st_theme_context_get_for_stage (CLUTTER_STAGE (stage));
+ g_object_get (context, "scale-factor", &paint_scale, NULL);
+
+ cache = st_texture_cache_get_default ();
+
+ if (priv->gicon != NULL)
+ priv->pending_texture = st_texture_cache_load_gicon (cache,
+ theme_node,
+ priv->gicon,
+ priv->icon_size,
+ paint_scale,
+ resource_scale);
+
+ if (priv->pending_texture == NULL && priv->fallback_gicon != NULL)
+ priv->pending_texture = st_texture_cache_load_gicon (cache,
+ theme_node,
+ priv->fallback_gicon,
+ priv->icon_size,
+ paint_scale,
+ resource_scale);
+
+ if (priv->pending_texture == NULL)
+ priv->pending_texture = st_texture_cache_load_gicon (cache,
+ theme_node,
+ default_gicon,
+ priv->icon_size,
+ paint_scale,
+ resource_scale);
+
+ if (priv->pending_texture)
+ {
+ g_object_ref_sink (priv->pending_texture);
+
+ if (clutter_actor_get_opacity (priv->pending_texture) != 0 || priv->icon_texture == NULL)
+ {
+ /* This icon is ready for showing, or nothing else is already showing */
+ st_icon_finish_update (icon);
+ }
+ else
+ {
+ /* Will be shown when fully loaded */
+ priv->opacity_handler_id = g_signal_connect_object (priv->pending_texture, "notify::opacity", G_CALLBACK (opacity_changed_cb), icon, 0);
+ }
+ }
+ else if (priv->icon_texture)
+ {
+ clutter_actor_destroy (priv->icon_texture);
+ priv->icon_texture = NULL;
+ }
+}
+
+static gboolean
+st_icon_update_icon_size (StIcon *icon)
+{
+ StIconPrivate *priv = icon->priv;
+ int new_size;
+
+ if (priv->prop_icon_size > 0)
+ new_size = priv->prop_icon_size;
+ else if (priv->theme_icon_size > 0)
+ {
+ gint scale;
+ ClutterActor *stage;
+ StThemeContext *context;
+
+ /* The theme will give us an already-scaled size, so we
+ * undo it here, as priv->icon_size is in unscaled pixels.
+ */
+ stage = clutter_actor_get_stage (CLUTTER_ACTOR (icon));
+ context = st_theme_context_get_for_stage (CLUTTER_STAGE (stage));
+ g_object_get (context, "scale-factor", &scale, NULL);
+ new_size = (gint) (priv->theme_icon_size / scale);
+ }
+ else
+ new_size = DEFAULT_ICON_SIZE;
+
+ if (new_size != priv->icon_size)
+ {
+ clutter_actor_queue_relayout (CLUTTER_ACTOR (icon));
+ priv->icon_size = new_size;
+ return TRUE;
+ }
+ else
+ return FALSE;
+}
+
+/**
+ * st_icon_new:
+ *
+ * Create a newly allocated #StIcon.
+ *
+ * Returns: A newly allocated #StIcon
+ */
+ClutterActor *
+st_icon_new (void)
+{
+ return g_object_new (ST_TYPE_ICON, NULL);
+}
+
+/**
+ * st_icon_get_icon_name:
+ * @icon: an #StIcon
+ *
+ * This is a convenience method to get the icon name of the current icon, if it
+ * is currenyly a #GThemedIcon, or %NULL otherwise.
+ *
+ * Returns: (transfer none) (nullable): The name of the icon or %NULL
+ */
+const gchar *
+st_icon_get_icon_name (StIcon *icon)
+{
+ StIconPrivate *priv;
+
+ g_return_val_if_fail (ST_IS_ICON (icon), NULL);
+
+ priv = icon->priv;
+
+ if (priv->gicon && G_IS_THEMED_ICON (priv->gicon))
+ return g_themed_icon_get_names (G_THEMED_ICON (priv->gicon)) [0];
+ else
+ return NULL;
+}
+
+/**
+ * st_icon_set_icon_name:
+ * @icon: an #StIcon
+ * @icon_name: (nullable): the name of the icon
+ *
+ * This is a convenience method to set the #GIcon to a #GThemedIcon created
+ * using the given icon name. If @icon_name is an empty string, %NULL or
+ * fails to load, the fallback icon will be shown.
+ */
+void
+st_icon_set_icon_name (StIcon *icon,
+ const gchar *icon_name)
+{
+ g_autoptr(GIcon) gicon = NULL;
+
+ g_return_if_fail (ST_IS_ICON (icon));
+
+ if (icon_name && *icon_name)
+ gicon = g_themed_icon_new_with_default_fallbacks (icon_name);
+
+ g_object_freeze_notify (G_OBJECT (icon));
+
+ st_icon_set_gicon (icon, gicon);
+ g_object_notify_by_pspec (G_OBJECT (icon), props[PROP_ICON_NAME]);
+
+ g_object_thaw_notify (G_OBJECT (icon));
+}
+
+/**
+ * st_icon_get_gicon:
+ * @icon: an #StIcon
+ *
+ * Gets the current #GIcon in use.
+ *
+ * Returns: (nullable) (transfer none): The current #GIcon, if set, otherwise %NULL
+ */
+GIcon *
+st_icon_get_gicon (StIcon *icon)
+{
+ g_return_val_if_fail (ST_IS_ICON (icon), NULL);
+
+ return icon->priv->gicon;
+}
+
+/**
+ * st_icon_set_gicon:
+ * @icon: an #StIcon
+ * @gicon: (nullable): a #GIcon
+ *
+ * Sets a #GIcon to show for the icon. If @gicon is %NULL or fails to load,
+ * the fallback icon set using st_icon_set_fallback_icon() will be shown.
+ */
+void
+st_icon_set_gicon (StIcon *icon, GIcon *gicon)
+{
+ g_return_if_fail (ST_IS_ICON (icon));
+ g_return_if_fail (gicon == NULL || G_IS_ICON (gicon));
+
+ if (g_icon_equal (icon->priv->gicon, gicon)) /* do nothing */
+ return;
+
+ g_set_object (&icon->priv->gicon, gicon);
+ g_object_notify_by_pspec (G_OBJECT (icon), props[PROP_GICON]);
+
+ st_icon_update (icon);
+}
+
+/**
+ * st_icon_get_fallback_gicon:
+ * @icon: a #StIcon
+ *
+ * Gets the currently set fallback #GIcon.
+ *
+ * Returns: (transfer none): The fallback #GIcon, if set, otherwise %NULL
+ */
+GIcon *
+st_icon_get_fallback_gicon (StIcon *icon)
+{
+ g_return_val_if_fail (ST_IS_ICON (icon), NULL);
+
+ return icon->priv->fallback_gicon;
+}
+
+/**
+ * st_icon_set_fallback_gicon:
+ * @icon: a #StIcon
+ * @fallback_gicon: (nullable): the fallback #GIcon
+ *
+ * Sets a fallback #GIcon to show if the normal icon fails to load.
+ * If @fallback_gicon is %NULL or fails to load, the icon is unset and no
+ * texture will be visible for the fallback icon.
+ */
+void
+st_icon_set_fallback_gicon (StIcon *icon,
+ GIcon *fallback_gicon)
+{
+ g_return_if_fail (ST_IS_ICON (icon));
+ g_return_if_fail (fallback_gicon == NULL || G_IS_ICON (fallback_gicon));
+
+ if (g_icon_equal (icon->priv->fallback_gicon, fallback_gicon))
+ return;
+
+ g_set_object (&icon->priv->fallback_gicon, fallback_gicon);
+ g_object_notify_by_pspec (G_OBJECT (icon), props[PROP_FALLBACK_GICON]);
+
+ st_icon_update (icon);
+}
+
+/**
+ * st_icon_get_icon_size:
+ * @icon: an #StIcon
+ *
+ * Gets the explicit size set using st_icon_set_icon_size() for the icon.
+ * This is not necessarily the size that the icon will be displayed at.
+ *
+ * Returns: The explicitly set size, or -1 if no size has been set
+ */
+gint
+st_icon_get_icon_size (StIcon *icon)
+{
+ g_return_val_if_fail (ST_IS_ICON (icon), -1);
+
+ return icon->priv->prop_icon_size;
+}
+
+/**
+ * st_icon_set_icon_size:
+ * @icon: an #StIcon
+ * @size: if positive, the new size, otherwise the size will be
+ * derived from the current style
+ *
+ * Sets an explicit size for the icon. Setting @size to -1 will use the size
+ * defined by the current style or the default icon size.
+ */
+void
+st_icon_set_icon_size (StIcon *icon,
+ gint size)
+{
+ StIconPrivate *priv;
+
+ g_return_if_fail (ST_IS_ICON (icon));
+
+ priv = icon->priv;
+ if (priv->prop_icon_size != size)
+ {
+ priv->prop_icon_size = size;
+ if (st_icon_update_icon_size (icon))
+ st_icon_update (icon);
+ g_object_notify_by_pspec (G_OBJECT (icon), props[PROP_ICON_SIZE]);
+ }
+}
+
+/**
+ * st_icon_get_fallback_icon_name:
+ * @icon: an #StIcon
+ *
+ * This is a convenience method to get the icon name of the fallback
+ * #GThemedIcon that is currently set.
+ *
+ * Returns: (transfer none): The name of the icon or %NULL if no icon is set
+ */
+const gchar *
+st_icon_get_fallback_icon_name (StIcon *icon)
+{
+ StIconPrivate *priv;
+
+ g_return_val_if_fail (ST_IS_ICON (icon), NULL);
+
+ priv = icon->priv;
+
+ if (priv->fallback_gicon && G_IS_THEMED_ICON (priv->fallback_gicon))
+ return g_themed_icon_get_names (G_THEMED_ICON (priv->fallback_gicon)) [0];
+ else
+ return NULL;
+}
+
+/**
+ * st_icon_set_fallback_icon_name:
+ * @icon: an #StIcon
+ * @fallback_icon_name: (nullable): the name of the fallback icon
+ *
+ * This is a convenience method to set the fallback #GIcon to a #GThemedIcon
+ * created using the given icon name. If @fallback_icon_name is an empty
+ * string, %NULL or fails to load, the icon is unset and no texture will
+ * be visible for the fallback icon.
+ */
+void
+st_icon_set_fallback_icon_name (StIcon *icon,
+ const gchar *fallback_icon_name)
+{
+ g_autoptr(GIcon) gicon = NULL;
+
+ g_return_if_fail (ST_IS_ICON (icon));
+
+ if (fallback_icon_name && *fallback_icon_name)
+ gicon = g_themed_icon_new_with_default_fallbacks (fallback_icon_name);
+
+ g_object_freeze_notify (G_OBJECT (icon));
+
+ st_icon_set_fallback_gicon (icon, gicon);
+ g_object_notify_by_pspec (G_OBJECT (icon), props[PROP_FALLBACK_ICON_NAME]);
+
+ g_object_thaw_notify (G_OBJECT (icon));
+}