general: Refactor view icon from a GIcon to an icon name

Most APIs these days receive icons in the form of `icon-name`,
and we need to manually set up widgets like `GtkImage` if
we must use a GIcon. In the case of the view icon, we use
it for a button, which takes `icon-name`. So, this commit
reworks the API to use an icon name instead of GIcon.

Use an empty string as a fallback value while the slot has
no content view. This avoids trying to set NULL as icon-name.

6 files changed, 26 insertions, 61 deletions

diff --git a/src/nautilus-toolbar.c b/src/nautilus-toolbar.c
index 6ea4c7cdc..04efd9df7 100644
--- a/src/nautilus-toolbar.c
+++ b/src/nautilus-toolbar.c
@@ -72,7 +72,6 @@ struct _NautilusToolbar
     GtkWidget *operations_icon;
 
     GtkWidget *view_split_button;
-    GtkWidget *view_toggle_icon;
     GMenuModel *view_menu;
 
     GtkWidget *app_button;
@@ -1180,7 +1179,6 @@ nautilus_toolbar_class_init (NautilusToolbarClass *klass)
     gtk_widget_class_bind_template_child (widget_class, NautilusToolbar, operations_revealer);
     gtk_widget_class_bind_template_child (widget_class, NautilusToolbar, view_menu);
     gtk_widget_class_bind_template_child (widget_class, NautilusToolbar, view_split_button);
-    gtk_widget_class_bind_template_child (widget_class, NautilusToolbar, view_toggle_icon);
     gtk_widget_class_bind_template_child (widget_class, NautilusToolbar, app_button);
     gtk_widget_class_bind_template_child (widget_class, NautilusToolbar, undo_redo_section);
     gtk_widget_class_bind_template_child (widget_class, NautilusToolbar, back_button);
@@ -1306,26 +1304,6 @@ disconnect_toolbar_menu_sections_change_handler (NautilusToolbar *self)
 }
 
 static gboolean
-nautilus_toolbar_view_toggle_icon_transform_to (GBinding     *binding,
-                                                const GValue *from_value,
-                                                GValue       *to_value,
-                                                gpointer      user_data)
-{
-    GIcon *icon;
-
-    icon = g_value_get_object (from_value);
-
-    /* As per design decision, we let the previous used icon if no
-     * view menu is available */
-    if (icon)
-    {
-        g_value_set_object (to_value, icon);
-    }
-
-    return TRUE;
-}
-
-static gboolean
 nautilus_toolbar_view_toggle_tooltip_transform_to (GBinding     *binding,
                                                    const GValue *from_value,
                                                    GValue       *to_value,
@@ -1363,13 +1341,9 @@ nautilus_toolbar_set_window_slot_real (NautilusToolbar    *self,
                            on_window_slot_destroyed,
                            self);
 
-        self->icon_binding = g_object_bind_property_full (self->window_slot, "icon",
-                                                          self->view_toggle_icon, "gicon",
-                                                          G_BINDING_DEFAULT | G_BINDING_SYNC_CREATE,
-                                                          (GBindingTransformFunc) nautilus_toolbar_view_toggle_icon_transform_to,
-                                                          NULL,
-                                                          self,
-                                                          NULL);
+        self->icon_binding = g_object_bind_property (self->window_slot, "icon-name",
+                                                     self->view_split_button, "icon-name",
+                                                     G_BINDING_DEFAULT | G_BINDING_SYNC_CREATE);
 
         /* HACK. We shouldn't be poking at internal children. But alas, no other option. */
         toggle_button = gtk_widget_get_parent (adw_split_button_get_child (ADW_SPLIT_BUTTON (self->view_split_button)));
diff --git a/src/nautilus-view.c b/src/nautilus-view.c
index 3efeeca05..2463ba632 100644
--- a/src/nautilus-view.c
+++ b/src/nautilus-view.c
@@ -110,27 +110,23 @@ nautilus_view_default_init (NautilusViewInterface *iface)
 }
 
 /**
- * nautilus_view_get_icon:
+ * nautilus_view_get_icon_name:
  * @view: a #NautilusView
  *
- * Retrieves the #GIcon that represents @view.
+ * Retrieves the icon name that represents @view.
  *
- * Returns: (transfer full): a #GIcon
+ * Returns: (transfer none): an icon name
  */
-GIcon *
-nautilus_view_get_icon (guint view_id)
+const gchar *
+nautilus_view_get_icon_name (guint view_id)
 {
     if (view_id == NAUTILUS_VIEW_GRID_ID)
     {
-        return g_themed_icon_new ("view-grid-symbolic");
+        return "view-grid-symbolic";
     }
-    else if (view_id == NAUTILUS_VIEW_LIST_ID)
-    {
-        return g_themed_icon_new ("view-list-symbolic");
-    }
-    else if (view_id == NAUTILUS_VIEW_OTHER_LOCATIONS_ID)
+    else if (view_id == NAUTILUS_VIEW_LIST_ID || view_id == NAUTILUS_VIEW_OTHER_LOCATIONS_ID)
     {
-        return g_themed_icon_new_with_default_fallbacks ("view-list-symbolic");
+        return "view-list-symbolic";
     }
     else
     {
diff --git a/src/nautilus-view.h b/src/nautilus-view.h
index 8a17b35de..9a8911e28 100644
--- a/src/nautilus-view.h
+++ b/src/nautilus-view.h
@@ -84,7 +84,7 @@ struct _NautilusViewInterface
         gboolean                        (*is_searching)              (NautilusView         *view);
 };
 
-GIcon *                        nautilus_view_get_icon                  (guint                 view_id);
+const gchar *                  nautilus_view_get_icon_name             (guint                 view_id);
 
 const gchar *                        nautilus_view_get_tooltip               (guint                 view_id);
 
diff --git a/src/nautilus-window-slot.c b/src/nautilus-window-slot.c
index 40fd5260f..976429e27 100644
--- a/src/nautilus-window-slot.c
+++ b/src/nautilus-window-slot.c
@@ -53,7 +53,7 @@ enum
 {
     PROP_ACTIVE = 1,
     PROP_WINDOW,
-    PROP_ICON,
+    PROP_ICON_NAME,
     PROP_TOOLBAR_MENU_SECTIONS,
     PROP_EXTENSIONS_BACKGROUND_MENU,
     PROP_TEMPLATES_MENU,
@@ -819,9 +819,9 @@ nautilus_window_slot_get_property (GObject    *object,
         }
         break;
 
-        case PROP_ICON:
+        case PROP_ICON_NAME:
         {
-            g_value_take_object (value, nautilus_window_slot_get_icon (self));
+            g_value_set_static_string (value, nautilus_window_slot_get_icon_name (self));
         }
         break;
 
@@ -2863,7 +2863,7 @@ nautilus_window_slot_switch_new_content_view (NautilusWindowSlot *self)
         self->templates_menu_binding = g_object_bind_property (self->content_view, "templates-menu",
                                                                self, "templates-menu",
                                                                G_BINDING_DEFAULT | G_BINDING_SYNC_CREATE);
-        g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_ICON]);
+        g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_ICON_NAME]);
         g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_TOOLBAR_MENU_SECTIONS]);
         g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_EXTENSIONS_BACKGROUND_MENU]);
         g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_TEMPLATES_MENU]);
@@ -3037,11 +3037,11 @@ nautilus_window_slot_class_init (NautilusWindowSlotClass *klass)
                              NAUTILUS_TYPE_WINDOW,
                              G_PARAM_READWRITE | G_PARAM_CONSTRUCT);
 
-    properties[PROP_ICON] =
-        g_param_spec_object ("icon",
+    properties[PROP_ICON_NAME] =
+        g_param_spec_string ("icon-name",
                              "Icon that represents the slot",
                              "The icon that represents the slot",
-                             G_TYPE_ICON,
+                             NULL,
                              G_PARAM_READABLE);
 
     properties[PROP_TOOLBAR_MENU_SECTIONS] =
@@ -3280,15 +3280,15 @@ nautilus_window_slot_new (NautilusWindow *window)
                          NULL);
 }
 
-GIcon *
-nautilus_window_slot_get_icon (NautilusWindowSlot *self)
+const gchar *
+nautilus_window_slot_get_icon_name (NautilusWindowSlot *self)
 {
     guint current_view_id;
     g_return_val_if_fail (NAUTILUS_IS_WINDOW_SLOT (self), NULL);
 
     if (self->content_view == NULL)
     {
-        return NULL;
+        return "";
     }
 
     current_view_id = nautilus_view_get_view_id (NAUTILUS_VIEW (self->content_view));
@@ -3296,19 +3296,19 @@ nautilus_window_slot_get_icon (NautilusWindowSlot *self)
     {
         case NAUTILUS_VIEW_LIST_ID:
         {
-            return nautilus_view_get_icon (NAUTILUS_VIEW_GRID_ID);
+            return nautilus_view_get_icon_name (NAUTILUS_VIEW_GRID_ID);
         }
         break;
 
         case NAUTILUS_VIEW_GRID_ID:
         {
-            return nautilus_view_get_icon (NAUTILUS_VIEW_LIST_ID);
+            return nautilus_view_get_icon_name (NAUTILUS_VIEW_LIST_ID);
         }
         break;
 
         case NAUTILUS_VIEW_OTHER_LOCATIONS_ID:
         {
-            return nautilus_view_get_icon (NAUTILUS_VIEW_OTHER_LOCATIONS_ID);
+            return nautilus_view_get_icon_name (NAUTILUS_VIEW_OTHER_LOCATIONS_ID);
         }
         break;
 
diff --git a/src/nautilus-window-slot.h b/src/nautilus-window-slot.h
index 3746e8fcd..364c63728 100644
--- a/src/nautilus-window-slot.h
+++ b/src/nautilus-window-slot.h
@@ -80,7 +80,7 @@ gboolean nautilus_window_slot_handle_event       	   (NautilusWindowSlot    *slo
 
 void    nautilus_window_slot_queue_reload		   (NautilusWindowSlot *slot);
 
-GIcon*   nautilus_window_slot_get_icon                     (NautilusWindowSlot *slot);
+const gchar*   nautilus_window_slot_get_icon_name                (NautilusWindowSlot *slot);
 
 const gchar*   nautilus_window_slot_get_tooltip                  (NautilusWindowSlot *slot);
 
diff --git a/src/resources/ui/nautilus-toolbar.ui b/src/resources/ui/nautilus-toolbar.ui
index 2ad5d49b1..b482f7da3 100644
--- a/src/resources/ui/nautilus-toolbar.ui
+++ b/src/resources/ui/nautilus-toolbar.ui
@@ -232,11 +232,6 @@
             <property name="tooltip_text" translatable="yes" comments="Translators: This is a noun, meaning the options pertaining to the view.">View options</property>
             <property name="action_name">slot.files-view-mode-toggle</property>
             <property name="menu-model">view_menu</property>
-            <child>
-              <object class="GtkImage" id="view_toggle_icon">
-                <property name="icon_size">1</property>
-              </object>
-            </child>
           </object>
         </child>
         <child type="end">