From 69c94a1919cdf423ede46dedf18c27b8c7fe36e5 Mon Sep 17 00:00:00 2001
From: William Jon McCann <jmccann@redhat.com>
Date: Jun 11 2010 00:51:10 +0000
Subject: Don't add all users to the model at once


Chunk the updates into groups of 50.  This is well more than can be displayed
in the visible part of the list anyway.  This prevents blocking the UI
while the model is loaded.

https://bugzilla.gnome.org/show_bug.cgi?id=621131

---

diff --git a/gui/simple-greeter/gdm-user-chooser-widget.c b/gui/simple-greeter/gdm-user-chooser-widget.c
index 0fdd950..40603f9 100644
--- a/gui/simple-greeter/gdm-user-chooser-widget.c
+++ b/gui/simple-greeter/gdm-user-chooser-widget.c
@@ -52,12 +52,15 @@ enum {
 #define GDM_USER_CHOOSER_WIDGET_GET_PRIVATE(o) (G_TYPE_INSTANCE_GET_PRIVATE ((o), GDM_TYPE_USER_CHOOSER_WIDGET, GdmUserChooserWidgetPrivate))
 
 #define MAX_ICON_SIZE 128
+#define NUM_USERS_TO_ADD_PER_ITERATION 50
 
 struct GdmUserChooserWidgetPrivate
 {
         GdmUserManager *manager;
         GtkIconTheme   *icon_theme;
 
+        GSList         *users_to_add;
+
         GdkPixbuf      *logged_in_pixbuf;
         GdkPixbuf      *stock_person_pixbuf;
 
@@ -71,6 +74,7 @@ struct GdmUserChooserWidgetPrivate
 
         guint           update_other_visibility_idle_id;
         guint           load_idle_id;
+        guint           add_users_idle_id;
 };
 
 enum {
@@ -547,6 +551,31 @@ on_user_changed (GdmUserManager       *manager,
         update_item_for_user (widget, user);
 }
 
+static gboolean
+add_users (GdmUserChooserWidget *widget)
+{
+        guint cnt;
+
+        cnt = 0;
+        while (widget->priv->users_to_add != NULL && cnt < NUM_USERS_TO_ADD_PER_ITERATION) {
+                add_user (widget, widget->priv->users_to_add->data);
+                g_object_unref (widget->priv->users_to_add->data);
+                widget->priv->users_to_add = g_slist_delete_link (widget->priv->users_to_add, widget->priv->users_to_add);
+                cnt++;
+        }
+        g_debug ("GdmUserChooserWidget: added %u items", cnt);
+
+        return (widget->priv->users_to_add != NULL);
+}
+
+static void
+queue_add_users (GdmUserChooserWidget *widget)
+{
+        if (widget->priv->add_users_idle_id == 0) {
+                widget->priv->add_users_idle_id = g_idle_add ((GSourceFunc) add_users, widget);
+        }
+}
+
 static void
 on_is_loaded_changed (GdmUserManager       *manager,
                       GParamSpec           *pspec,
@@ -555,13 +584,15 @@ on_is_loaded_changed (GdmUserManager       *manager,
         GSList *users;
         gboolean list_visible;
 
+        /* FIXME: handle is-loaded=FALSE */
+
         g_debug ("GdmUserChooserWidget: Users loaded");
 
         users = gdm_user_manager_list_users (manager);
-        while (users != NULL) {
-                add_user (widget, users->data);
-                users = g_slist_delete_link (users, users);
-        }
+        g_slist_foreach (users, (GFunc) g_object_ref, NULL);
+        widget->priv->users_to_add = g_slist_concat (widget->priv->users_to_add, g_slist_copy (users));
+
+        queue_add_users (widget);
 
         g_object_get (G_OBJECT (widget), "list-visible", &list_visible, NULL);
 
@@ -641,11 +672,22 @@ gdm_user_chooser_widget_dispose (GObject *object)
                 widget->priv->load_idle_id = 0;
         }
 
+        if (widget->priv->add_users_idle_id > 0) {
+                g_source_remove (widget->priv->add_users_idle_id);
+                widget->priv->add_users_idle_id = 0;
+        }
+
         if (widget->priv->update_other_visibility_idle_id > 0) {
                 g_source_remove (widget->priv->update_other_visibility_idle_id);
                 widget->priv->update_other_visibility_idle_id = 0;
         }
 
+        if (widget->priv->users_to_add != NULL) {
+                g_slist_foreach (widget->priv->users_to_add, (GFunc) g_object_ref, NULL);
+                g_slist_free (widget->priv->users_to_add);
+                widget->priv->users_to_add = NULL;
+        }
+
         if (widget->priv->logged_in_pixbuf != NULL) {
                 g_object_unref (widget->priv->logged_in_pixbuf);
                 widget->priv->logged_in_pixbuf = NULL;