fixes #3648

Closes #3648

Merge request studip/studip!2523

app/views/resources/room_request/planning.php

@@ -134,7 +134,7 @@
     <?= MessageBox::info(_('Es wurde kein Raum ausgewählt!')) ?>
 <? endif ?>
 
-<? if ($requests && $resource): ?>
+<? if (isset($requests, $resource)): ?>
     <form class="default" method="post"
           action="<?= $controller->link_for('room_request/assign') ?>">
         <table id="external-events" class="default request-list">

lib/classes/forms/RangeInput.php

@@ -11,9 +11,9 @@ class RangeInput extends Input
         $template->name = $this->name;
         $template->value = $this->value;
         $template->id = md5(uniqid());
-        $template->min = $this->attributes['min'];
-        $template->max = $this->attributes['max'];
-        $template->step = $this->attributes['step'];
+        $template->min = $this->attributes['min'] ?? null;
+        $template->max = $this->attributes['max'] ?? null;
+        $template->step = $this->attributes['step'] ?? null;
         $template->required = $this->required;
         $template->attributes = arrayToHtmlAttributes($this->attributes);
         return $template->render();