From f6bb712e3acdc2330336cb5b21d5b41f269514be Mon Sep 17 00:00:00 2001
From: Dan Marsden <dan@danmarsden.com>
Date: Tue, 15 Mar 2016 09:02:06 +1300
Subject: [PATCH] Fixes #190 Show warning message when no users in course

---
 export_form.php        | 8 +++++++-
 lang/en/attendance.php | 1 +
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/export_form.php b/export_form.php
index ba048e5..c53ff71 100644
--- a/export_form.php
+++ b/export_form.php
@@ -58,7 +58,6 @@ class mod_attendance_export_form extends moodleform {
                 $grouplist[$group->id] = $group->name;
             }
         }
-        $mform->addElement('select', 'group', get_string('group'), $grouplist);
 
         // Restrict the export to the selected users.
         $namefields = get_all_user_name_fields(true, 'u');
@@ -72,6 +71,11 @@ class mod_attendance_export_form extends moodleform {
         foreach ($tempusers as $user) {
             $userlist[$user->studentid] = $user->fullname;
         }
+        if (empty($userlist)) {
+            $mform->addElement('static', 'nousers', '', get_string('noattendanceusers', 'attendance'));
+            return;
+        }
+
         list($gsql, $gparams) = $DB->get_in_or_equal(array_keys($grouplist), SQL_PARAMS_NAMED);
         list($usql, $uparams) = $DB->get_in_or_equal(array_keys($userlist), SQL_PARAMS_NAMED);
         $params = array_merge($gparams, $uparams);
@@ -88,6 +92,8 @@ class mod_attendance_export_form extends moodleform {
             $groupmappings[0] = $userlist;
         }
 
+        $mform->addElement('select', 'group', get_string('group'), $grouplist);
+
         $mform->addElement('selectyesno', 'selectedusers', get_string('onlyselectedusers', 'mod_attendance'));
         $sel = $mform->addElement('select', 'users', get_string('users', 'mod_attendance'), $userlist, array('size' => 12));
         $sel->setMultiple(true);
diff --git a/lang/en/attendance.php b/lang/en/attendance.php
index 2ec8406..7871676 100644
--- a/lang/en/attendance.php
+++ b/lang/en/attendance.php
@@ -312,3 +312,4 @@ $string['hiddensessionsdeleted'] = 'All hidden sessions were delete';
 
 $string['timeahead'] = 'Multiple sessions that exceed one year cannot be created, please adjust the start and end dates.';
 $string['priorto'] = 'The session date is prior to the course start date ({$a}) so that the new sessions scheduled before this date will be hidden (not accessible). You can change the course start date at any time (see course settings) in order to have access to earlier sessions.<br><br>Please change the session date or just click the "Add session" button again to confirm?';
+$string['noattendanceusers'] = 'It is not possible to export any data as there are no students enrolled in the course.';