public function build()
    {
        if ($this->isBuild) {
            return;
        }

        $settings = $this->getObject();
        $form     = $this->formManager->get($settings->getForm());

        $this->setLabel(
            $form->getOption('settings_label') ?: sprintf(
                /*@translate*/ 'Customize enabled elements for %s',
                get_class($form)
            )
        );

        $this->add(
            array(
            'type' => 'Checkbox',
            'name' => 'isActive',
            'options' => array(
                'label' => /*@translate*/ 'Activate',
                'long_label' => /*@translate*/ 'Enables the form element customization.',
            ),
            'attributes' => array(
                'class' => 'decfs-active-toggle',
            ),
            )
        );
        $element = new DisableElementsCapableFormSettings('disableElements');
        $element->setForm($form);
        $this->add($element);

        $this->isBuild = true;
    }