[nautilus] canvas-container: cache icon positions for accessibles

[Cosimo Cecchi <cosimoc src gnome org>]

commit aa5fb604de6d284af8beb015f912d56f1dac1851
Author: Cosimo Cecchi <cosimoc gnome org>
Date:   Mon Sep 1 12:20:00 2014 -0700

    canvas-container: cache icon positions for accessibles
    
    Instead of calling g_list_index() every time, cache positions when
    resorting.

 libnautilus-private/nautilus-canvas-container.c |   22 ++++++++++++++++------
 libnautilus-private/nautilus-canvas-private.h   |    3 +++
 2 files changed, 19 insertions(+), 6 deletions(-)
---
diff --git a/libnautilus-private/nautilus-canvas-container.c b/libnautilus-private/nautilus-canvas-container.c
index 098d401..3d0cf7d 100644
--- a/libnautilus-private/nautilus-canvas-container.c
+++ b/libnautilus-private/nautilus-canvas-container.c
@@ -1102,6 +1102,19 @@ nautilus_canvas_container_update_scroll_region (NautilusCanvasContainer *contain
        }
 }
 
+static void
+cache_icon_positions (NautilusCanvasContainer *container)
+{
+       GList *l;
+       gint idx;
+       NautilusCanvasIcon *icon;
+
+       for (l = container->details->icons, idx = 0; l != NULL; l = l ->next) {
+               icon = l->data;
+               icon->position = idx++;
+       }
+}
+
 static int
 compare_icons_data (gconstpointer a, gconstpointer b, gpointer canvas_container)
 {
@@ -1154,6 +1167,7 @@ resort (NautilusCanvasContainer *container)
 {
        sort_icons (container, &container->details->icons);
        sort_selection (container);
+       cache_icon_positions (container);
 }
 
 typedef struct {
@@ -7666,17 +7680,15 @@ nautilus_canvas_container_accessible_icon_added_cb (NautilusCanvasContainer *con
        NautilusCanvasIcon *icon;
        AtkObject *atk_parent;
        AtkObject *atk_child;
-       int index;
 
        icon = g_hash_table_lookup (container->details->icon_set, icon_data);
        if (icon) {
                atk_parent = ATK_OBJECT (data);
                atk_child = atk_gobject_accessible_for_object 
                        (G_OBJECT (icon->item));
-               index = g_list_index (container->details->icons, icon);
                
                g_signal_emit_by_name (atk_parent, "children-changed::add",
-                                      index, atk_child, NULL);
+                                      icon->position, atk_child, NULL);
        }
 }
 
@@ -7688,17 +7700,15 @@ nautilus_canvas_container_accessible_icon_removed_cb (NautilusCanvasContainer *c
        NautilusCanvasIcon *icon;
        AtkObject *atk_parent;
        AtkObject *atk_child;
-       int index;
        
        icon = g_hash_table_lookup (container->details->icon_set, icon_data);
        if (icon) {
                atk_parent = ATK_OBJECT (data);
                atk_child = atk_gobject_accessible_for_object 
                        (G_OBJECT (icon->item));
-               index = g_list_index (container->details->icons, icon);
                
                g_signal_emit_by_name (atk_parent, "children-changed::remove",
-                                      index, atk_child, NULL);
+                                      icon->position, atk_child, NULL);
        }
 }
 
diff --git a/libnautilus-private/nautilus-canvas-private.h b/libnautilus-private/nautilus-canvas-private.h
index bfccf19..d624556 100644
--- a/libnautilus-private/nautilus-canvas-private.h
+++ b/libnautilus-private/nautilus-canvas-private.h
@@ -52,6 +52,9 @@ typedef struct {
        /* Scale factor (stretches icon). */
        double scale;
 
+       /* Position in the view */
+       int position;
+
        /* Whether this item is selected. */
        eel_boolean_bit is_selected : 1;