Default options form that provides the label widget that all fields should have.
Overrides FieldPluginBase::buildOptionsForm
public function buildOptionsForm(&$form, &$form_state) {
$form['text'] = array(
'#type' => 'textfield',
'#title' => t('Text to display'),
'#default_value' => $this->options['text'],
);
$form['link_to_node'] = array(
'#title' => t('Link field to the node if there is no comment.'),
'#type' => 'checkbox',
'#default_value' => $this->options['link_to_node'],
);
parent::buildOptionsForm($form, $form_state);
}