Fixing PHP warnings #7225

main/inc/lib/plugin.class.php

@@ -208,12 +208,18 @@ class Plugin
                     $result->addGroup($group, null, array($this->get_lang($name), $help));
                     break;
                 case 'checkbox':
+                    $selectedValue = null;
+                    if (isset($checkboxCollection[$name])) {
+                        if ($checkboxCollection[$name]['selected_value'] === 'true') {
+                            $selectedValue = 'checked';
+                        }
+                    }
                     $element = $result->createElement(
                         $type,
                         $name,
                         '',
                         $this->get_lang($name),
-                        $checkboxCollection[$name]['selected_value'] === 'true' ? 'checked' : ''
+                        $selectedValue
                     );
                     $element->_attributes['value'] = 'true';
                     $checkboxGroup[] = $element;