public function heading()
    {
        $heading = $this->render((string)$this->heading);

        if (!$heading) {
            $heading = $this->translator()->translation('{{ objType }} #{{ id }}', [
                '{{ objType }}' => ucfirst($this->microType()),
                '{{ id }}'      => $this->id()
            ]);
        }

        return $heading;
    }