add order to additional images

src/News.php

@@ -80,6 +80,37 @@ class News extends \Contao\News
                 /** @var \PageModel $objPage */
                 global $objPage;
 
+                if ($arrItem['orderSRC'])
+                {
+                         $tmp = StringUtil::deserialize($arrItem['orderSRC']);
+
+                         if (!empty($tmp) && \is_array($tmp))
+                         {
+                                 // Remove all values
+                                 $arrOrder = array_map(static function () {}, array_flip($tmp));
+
+                                 // Move the matching elements to their position in $arrOrder
+                                 foreach ($arrItem['multiSRC'] as $k=>$v)
+                                 {
+                                         if (\array_key_exists($v['uuid'], $arrOrder))
+                                         {
+                                                 $arrOrder[$v['uuid']] = $v;
+                                                 unset($arrItem['multiSRC'][$k]);
+                                         }
+                                 }
+
+                                 // Append the left-over images at the end
+                                 if (!empty($arrItem['multiSRC']))
+                                 {
+					 $arrOrder = array_merge($arrOrder, array_values($arrItem['multiSRC']));
+                                 }
+
+                                 // Remove empty (unreplaced) entries
+                                 $arrItem['multiSRC'] = array_values(array_filter($arrOrder));
+                                 unset($arrOrder);
+                         }
+                 }
+
                 $pictures = array();
                 foreach ($arrItem['multiSRC'] as $path => $objFile)
                 {