Gravity Forms sub menu item

gravity-forms-submenu-item.php

/* Add 'Entry Reports' to Gravity Forms 'Settings' form page */
add_filter( 'gform_form_settings_menu', 'gfer_form_settings_menu_item' );
function gfer_form_settings_menu_item( $menu_items ) {
  $menu_items[] = array(
    'name'          => 'gfer_form_settings_page',
    'label'         => __('Entry Reports', 'gravity-forms-entry-reports'),
    'title'         => __('Entry Reports', 'gravity-forms-entry-reports'),
    'menu_class'    => 'gfer_settings_navigation',
    'link_class'    => '',
    'capabilities'  => array( 'gravityforms_edit_forms' ),
    'icon'          => 'dashicons-chart-bar dashicons',
    'priority'      => 500
  );
  return $menu_items;
}


// handle displaying content for our custom menu when selected
add_action( 'gform_form_settings_page_gfer_form_settings_page', 'gfer_form_settings_page' );
function gfer_form_settings_page() {
  
    GFFormSettings::page_header(); ?>
  
    <fieldset id="gform-settings-section-form-basics" class="gform-settings-panel gform-settings-panel--with-title">
        <legend class="gform-settings-panel__title gform-settings-panel__title--header"><?php _e('Entry Reports', 'gravity-forms-entry-reports'); ?></legend>

        <div class="gform-settings-panel__content">
            Stuff goes here
        </div>

    </fieldset>
    <?php GFFormSettings::page_footer();
}