Preview setting (as image):
'preview' => get_template_directory_uri() . 'some_url.jpg',
'field' => array(
'type' => 'radio',
'label' => esc_html__('Radio Button', 'my-domain'),
'submenu' => esc_html__('General fields', 'my-domain'),
'options' => array(
1 => 'One',
2 => 'Two',
3 => 'Three',
4 => 'Four',
),
'previews' => array(
1 => get_template_directory_uri() . 'some_url_1.jpg',
2 => get_template_directory_uri() . 'some_url_2.jpg',
3 => get_template_directory_uri() . 'some_url_3.jpg',
4 => get_template_directory_uri() . 'some_url_4.jpg',
),
'description' => esc_html__('Manage create listing page section titles front-end and admin', 'my-domain'),
),