sites.php

add_shortcode( 'ss-site-form', 'ss_frontend_form_shortcode' );
/**
 * Shortcode to display a CMB2 form for a post ID.
 * @param  array  $atts Shortcode attributes
 * @return string       Form HTML markup
 */
function ss_frontend_form_shortcode( $atts = array() ) {

	global $post;

	//var_dump($atts);
	/**
	 * Depending on your setup, check if the user has permissions to edit_posts
	 */
	if ( ! current_user_can( 'edit_posts' ) ) {
		return _e( 'You do not have permissions to edit this post.', 'lang_domain' );
	}
	/**
	 * Make sure a WordPress post ID is set.
	 * We'll default to the current post/page
	 */
	if ( ! isset( $atts['post_id'] ) ) {
		$atts['post_id'] = $post->ID;
	}
	// If no metabox id is set, yell about it
	if ( empty( $atts['id'] ) ) {
		return "Please add a 'id' attribute to specify the CMB2 form to display.";
	}
	$metabox_id = esc_attr( $atts['id'] );
	$object_id  = absint( $atts['post_id'] );
	// Get our form
	$form = cmb2_get_metabox_form( $metabox_id, $object_id );

	return $form;

}




function site_title() {

	$user_array = ss_list_array();

	foreach ($user_array['sites'] as $site) {
		$title = $site['post_title'];;
		echo '<li><a href="">'.$title.'</a></li>';

	}


}


function site_tab() {

	$user_array = ss_list_array();

	foreach ($user_array['sites'] as $site) {

		// vars
		$post_id =  $site['post_id'];
		$meta_id = 'site_meta';
		$atts = array (
			'id' => $meta_id,
			'post_id' => (string)$post_id
		);

		//var_dump($atts);

		echo '<li>'.do_shortcode('[ss-site-form post_id='. $post_id .' id='. $meta_id .' ]').'</li>';
		//ss_frontend_form_shortcode($atts);



	}
}



?>

<h1>Site Settings</h1>

<div class="uk-alert uk-alert-warning">Your sites will be displayed below.</div>

<div class="uk-grid">
		<!-- This is the vertical tabbed navigation containing the toggling elements -->

		<ul class="uk-tab uk-tab-left col-md-4" data-uk-tab="{connect:'#my-id'}">
			<?php site_title(); ?>
		</ul>
		<!-- This is the container of the content items -->
		<ul id="my-id" class="uk-switcher col-med-8 container">
				<?php site_tab(); ?>
		</ul>
</div>