Fixes #724, Only retrieves files with derivative images when using th…

…e item_image helper.

application/helpers/NewThemeFunctions.php

@@ -801,8 +801,9 @@ function item_image($imageType, $props = array(), $index = 0, $item = null)
     if (!$item) {
         $item = get_current_item();
     }
-
-    $imageFile = $item->Files[$index];
+
+	$imageFile = get_db()->getTable('File')->findWithImages($item->id, $index);
+
     $width = @$props['width'];
     $height = @$props['height'];
 

application/models/FileTable.php

@@ -59,4 +59,23 @@ public function findByItem($item_id, $fileIds = array())
         }
         return $this->fetchObjects($select, array($item_id));
     }
+
+    /**
+     * Retrieve file that has derivative images.
+     * 
+     * @param integer $itemId
+     * @param integer $index Optional If given, this specifies the file to
+	 * retrieve for an item, based upon the ordering of its derivative files.
+	 *
+     * @return array
+     **/
+	public function findWithImages($item_id, $index=0)
+	{
+		$select = $this->getSelect()
+					   ->where('f.item_id = ? AND f.has_derivative_image = 1')
+					   ->order('f.item_id ASC')
+					   ->limitPage($index, 1);
+
+		return $this->fetchObject($select, array($item_id));
+	}
 }