public function updateSearchForm(Form $form)
    {
        if ($this->isVersioned()) {
            
            // Obtain Field List:
            
            $fields = $form->Fields();
            
            // Create Filter Field:
            
            $filter = DropdownField::create(
                'q[FilterClass]',
                $this->owner->getStatusFieldTitle(),
                $this->getFilterClassOptions(),
                $this->getFilterClass()
            )->setForm($form);
            
            // Add Filter Field to Form:
            
            if ($this->owner->StatusFieldBefore) {
                $fields->insertBefore(sprintf('q[%s]', $this->owner->StatusFieldBefore), $filter);
            } elseif ($this->owner->StatusFieldAfter) {
                $fields->insertAfter(sprintf('q[%s]', $this->owner->StatusFieldAfter), $filter);
            } else {
                $fields->push($filter);
            }
            
        }
    }