MDL-13722, MDL-12909 - idnumber required in xml grade export, if not present do not show user in export preview

grade/export/lib.php

@@ -191,8 +191,9 @@ class grade_export {
 
     /**
      * Prints preview of exported grades on screen as a feedback mechanism
+     * @param bool $require_user_idnumber true means skip users without idnumber
      */
-    function display_preview() {
+    function display_preview($require_user_idnumber=false) {
 
         print_heading(get_string('previewrows', 'grades'));
 
@@ -224,10 +225,11 @@ class grade_export {
                 break;
             }
             $user = $userdata->user;
-            // if (empty($user->idnumber)) {   // Not sure why this was here, ccommented out for MDL-13722
-            //     continue;
-            // }
-            
+            if ($require_user_idnumber and empty($user->idnumber)) {
+                // some exports require user idnumber
+                continue;
+            }
+
             $gradeupdated = false; // if no grade is update at all for this user, do not display this row
             $rowstr = '';
             foreach ($this->columns as $itemid=>$unused) {

grade/export/xml/index.php

@@ -54,7 +54,7 @@ if ($data = $mform->get_data()) {
     // print the grades on screen for feedbacks
     $export->process_form($data);
     $export->print_continue();
-    $export->display_preview();
+    $export->display_preview(true);
     print_footer($course);
     exit;
 }