Add admin settings

lib.php

+<?php
+// This file is part of Moodle - https://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <https://www.gnu.org/licenses/>.
+
+/**
+ * Plugin administration pages are defined here.
+ *
+ * @package     local_hshexport
+ * @copyright   2024 Elke Kreim elke.kreim@hs-hannover.de
+ * @license     https://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+define('LOCALHSHEXPORT_NAV_COURSE', 'navcourse');
+define('LOCALHSHEXPORT_NAV_PARTICIPANTS', 'navpart');
\ No newline at end of file

settings.php

@@ -23,13 +23,30 @@
  * @license     https://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
 
+
 defined('MOODLE_INTERNAL') || die();
 
+// Require library.
+require_once($CFG->dirroot.'/local/hshexport/lib.php');
+
 if ($hassiteconfig) {
     $settings = new admin_settingpage('local_hshexport_settings', new lang_string('pluginname', 'local_hshexport'));
 
     // phpcs:ignore Generic.CodeAnalysis.EmptyStatement.DetectedIf
     if ($ADMIN->fulltree) {
-        // TODO: Define actual plugin settings page and add it to the tree - {@link https://docs.moodle.org/dev/Admin_settings}.
+        // Create navigation node placement widget.
+        $navigationoptions = [LOCALHSHEXPORT_NAV_COURSE => get_string('nav_course', 'local_hshexport'),
+            LOCALHSHEXPORT_NAV_PARTICIPANTS => get_string('nav_participants', 'local_hshexport')];
+        $settings->add(
+            new admin_setting_configselect(
+                'local_hshexport/navigation',
+                get_string('navigation', 'local_hshexport'),
+                get_string('navigation_desc', 'local_hshexport'),
+                LOCALHSHEXPORT_NAV_PARTICIPANTS,
+                $navigationoptions)
+        );
+        unset($navigationoptions);
     }
+
+    $ADMIN->add('localplugins', $settings);
 }