[gnome-control-center] background: Async function for loading XML wallpapers

[Bastien Nocera <hadess src gnome org>]

commit 7b287b8c03f3c272711239d9c4c2546d53ebe6bf
Author: Bastien Nocera <hadess hadess net>
Date:   Thu Feb 10 12:01:17 2011 +0000

    background: Async function for loading XML wallpapers
    
    It's ugly API, but it means we don't block anymore.

 panels/background/bg-wallpapers-source.c |   28 +++++++++++++++-------
 panels/background/gnome-wp-xml.c         |   37 ++++++++++++++++++++++++++++++
 panels/background/gnome-wp-xml.h         |   10 ++++++++
 3 files changed, 66 insertions(+), 9 deletions(-)
---
diff --git a/panels/background/bg-wallpapers-source.c b/panels/background/bg-wallpapers-source.c
index 8b76007..c9a95d5 100644
--- a/panels/background/bg-wallpapers-source.c
+++ b/panels/background/bg-wallpapers-source.c
@@ -194,6 +194,24 @@ load_wallpapers (gchar              *key,
   gtk_tree_path_free (path);
 }
 
+static void
+list_load_cb (GObject *source_object,
+	      GAsyncResult *res,
+	      gpointer user_data)
+{
+  BgWallpapersSource *self = (BgWallpapersSource *) user_data;
+  GnomeWpXml *wp_xml;
+
+  wp_xml = gnome_wp_xml_load_list_finish (res);
+  g_hash_table_foreach (wp_xml->wp_hash,
+			(GHFunc) load_wallpapers,
+			self);
+
+  g_hash_table_destroy (wp_xml->wp_hash);
+  g_object_unref (wp_xml->settings);
+  g_free (wp_xml);
+}
+
 static gboolean
 reload_wallpapers (BgWallpapersSource *self)
 {
@@ -208,15 +226,7 @@ reload_wallpapers (BgWallpapersSource *self)
   wp_xml->thumb_height = THUMBNAIL_HEIGHT;
   wp_xml->thumb_factory = self->priv->thumb_factory;
 
-  gnome_wp_xml_load_list (wp_xml);
-  g_hash_table_foreach (wp_xml->wp_hash,
-                        (GHFunc) load_wallpapers,
-                        self);
-
-  g_hash_table_destroy (wp_xml->wp_hash);
-  g_object_unref (wp_xml->settings);
-  g_free (wp_xml);
-
+  gnome_wp_xml_load_list_async (wp_xml, NULL, list_load_cb, self);
   self->priv->reload_id = 0;
 
   return FALSE;
diff --git a/panels/background/gnome-wp-xml.c b/panels/background/gnome-wp-xml.c
index 46bddc2..2783226 100644
--- a/panels/background/gnome-wp-xml.c
+++ b/panels/background/gnome-wp-xml.c
@@ -318,6 +318,43 @@ void gnome_wp_xml_load_list (GnomeWpXml *data) {
   }
 }
 
+GnomeWpXml *
+gnome_wp_xml_load_list_finish (GAsyncResult  *async_result)
+{
+	GSimpleAsyncResult *result = G_SIMPLE_ASYNC_RESULT (async_result);
+
+	g_return_val_if_fail (G_IS_ASYNC_RESULT (async_result), NULL);
+	g_warn_if_fail (g_simple_async_result_get_source_tag (result) == gnome_wp_xml_load_list_async);
+
+	return g_simple_async_result_get_op_res_gpointer (result);
+}
+
+static void
+load_list_thread (GSimpleAsyncResult *res,
+		  GObject *object,
+		  GCancellable *cancellable)
+{
+	GnomeWpXml *data;
+
+	data = g_simple_async_result_get_op_res_gpointer (res);
+	gnome_wp_xml_load_list (data);
+}
+
+void gnome_wp_xml_load_list_async (GnomeWpXml *data,
+				   GCancellable *cancellable,
+				   GAsyncReadyCallback callback,
+				   gpointer user_data)
+{
+	GSimpleAsyncResult *result;
+
+	g_return_if_fail (data != NULL);
+
+	result = g_simple_async_result_new (NULL, callback, user_data, gnome_wp_xml_load_list_async);
+	g_simple_async_result_set_op_res_gpointer (result, data, NULL);
+	g_simple_async_result_run_in_thread (result, (GSimpleAsyncThreadFunc) load_list_thread, G_PRIORITY_LOW, cancellable);
+	g_object_unref (result);
+}
+
 static void gnome_wp_list_flatten (const gchar * key, GnomeWPItem * item,
 				   GSList ** list) {
   g_return_if_fail (key != NULL);
diff --git a/panels/background/gnome-wp-xml.h b/panels/background/gnome-wp-xml.h
index 2140a61..178e2cb 100644
--- a/panels/background/gnome-wp-xml.h
+++ b/panels/background/gnome-wp-xml.h
@@ -22,6 +22,7 @@
 #define _GNOME_WP_XML_H_
 
 #include <libgnome-desktop/gnome-desktop-thumbnail.h>
+#include <gio/gio.h>
 
 typedef struct _GnomeWpXml GnomeWpXml;
 
@@ -37,6 +38,15 @@ struct _GnomeWpXml
 
 void gnome_wp_xml_load_list (GnomeWpXml *data);
 void gnome_wp_xml_save_list (GnomeWpXml *data);
+/* FIXME this should be an iterator instead, so the bg
+ * pops up as soon as a new one is available */
+void gnome_wp_xml_load_list_async (GnomeWpXml *data,
+				   GCancellable *cancellable,
+				   GAsyncReadyCallback callback,
+				   gpointer user_data);
+/* FIXME, this is ugly API, which wouldn't be
+ * needed if this was an object */
+GnomeWpXml *gnome_wp_xml_load_list_finish (GAsyncResult  *async_result);
 
 #endif