Replace custom tpl with a generic, fix php error, fix message BT#10882

when adding users to a LP category.0

main/lp/lp_subscribe_users_to_category.php

@@ -48,11 +48,12 @@ $interbreadcrumb[] = ['url' => '#', 'name' => strip_tags($category->getName())];
 
 $url = api_get_self().'?'.api_get_cidreq().'&action=add_users_to_category&id='.$categoryId;
 
-Display::addFlash(Display::return_message(get_lang('UserLpCategorySubscriptionDescription')));
+$message = Display::return_message(get_lang('UserLpCategorySubscriptionDescription'));
 
 // Building the form for Groups
 $form = new FormValidator('lp_edit', 'post', $url);
 $form->addElement('hidden', 'group_form', 1);
+$form->addLabel('', $message);
 
 // Group list
 $groupList = \CourseManager::get_group_list_of_course(
@@ -119,7 +120,6 @@ foreach ($subscribedUsers as $user) {
 
 // Getting subscribed users to a category.
 $subscribedUsersInCategory = $category->getUsers();
-
 $selectedChoices = [];
 foreach ($subscribedUsersInCategory as $item) {
     $selectedChoices[] = $item->getUser()->getId();
@@ -128,6 +128,7 @@ foreach ($subscribedUsersInCategory as $item) {
 // Building the form for Users
 $formUsers = new FormValidator('lp_edit', 'post', $url);
 $formUsers->addElement('hidden', 'user_form', 1);
+$formUsers->addLabel('', $message);
 
 $userMultiSelect = $formUsers->addElement(
     'advmultiselect',
@@ -138,7 +139,6 @@ $userMultiSelect = $formUsers->addElement(
 $formUsers->addButtonSave(get_lang('Save'));
 
 $defaults = [];
-
 if (!empty($selectedChoices)) {
     $defaults['users'] = $selectedChoices;
 }
@@ -205,8 +205,6 @@ if ($formUsers->validate()) {
         get_lang('SubscribeGroupsToLpCategory')
     ];
     $tabs = Display::tabs($headers, [$formUsers->toHtml(), $form->toHtml()]);
-    $tpl->assign('tabs', $tabs);
+    $tpl->assign('content', $tabs);
+    $tpl->display_one_col_template();
 }
-
-$layout = $tpl->get_template('learnpath/subscribe_users.tpl');
-$tpl->display($layout);