tracker: Use property function for sorting

Tracker claims to be more efficient when using property functions instead
of variables. Property functions work just fine for sorting too. This
patch uses property function instead of variable for modified date
sorting.

diff --git a/src/plugins/tracker/rygel-tracker-search-container.vala b/src/plugins/tracker/rygel-tracker-search-container.vala
index de5934b..335bbaf 100644 (file)
--- a/src/plugins/tracker/rygel-tracker-search-container.vala
+++ b/src/plugins/tracker/rygel-tracker-search-container.vala
@@ -35,8 +35,7 @@ public class Rygel.Tracker.SearchContainer : Rygel.MediaContainer {
     private const string TRACKER_SERVICE = "org.freedesktop.Tracker1";
     private const string RESOURCES_PATH = "/org/freedesktop/Tracker1/Resources";
 
-    private const string MODIFIED_PREDICATE = "nfo:fileLastModified";
-    private const string MODIFIED_VARIABLE = "?modified";
+    private const string MODIFIED_PROPERTY = "nfo:fileLastModified";
 
     public SelectionQuery query;
     public ItemFactory item_factory;
@@ -67,10 +66,6 @@ public class Rygel.Tracker.SearchContainer : Rygel.MediaContainer {
                                         (SelectionQuery.ITEM_VARIABLE,
                                          "a",
                                          item_factory.category));
-        our_triplets.add_triplet (new QueryTriplet
-                                        (SelectionQuery.ITEM_VARIABLE,
-                                         MODIFIED_PREDICATE,
-                                         MODIFIED_VARIABLE));
 
         foreach (var chain in this.item_factory.key_chains) {
             var variable = SelectionQuery.ITEM_VARIABLE;
@@ -82,10 +77,15 @@ public class Rygel.Tracker.SearchContainer : Rygel.MediaContainer {
             variables.add (variable);
         }
 
+        var order_by = MODIFIED_PROPERTY +
+                       "(" +
+                       SelectionQuery.ITEM_VARIABLE +
+                       ")";
+
         this.query = new SelectionQuery (variables,
                                          our_triplets,
                                          filters,
-                                         MODIFIED_VARIABLE);
+                                         order_by);
 
         try {
             this.resources = Bus.get_proxy_sync