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<?php
// Sample code to display fields on frontend - put in a hookbox in Dynamik, for example, or in your custom template
                    $text  = esc_html (get_post_meta( get_the_ID(), '_siga_text', true ));
                    $email = is_email(get_post_meta( get_the_ID(), '_siga_email', true ));
                    $url   = esc_url(get_post_meta( get_the_ID(), '_siga_url', true ));
                    $output = '';
					          
	// Only display the fields if we have all the data. Define your required fields here.
	if ( $text && $email && $url ) {
		echo '<p>' . $text . '<br>' . $email . '<br>' . $url . '</p>';
	}
	// Else display nothing to avoid empty HTML tags being added				
	else {		
         return $output;
	}
?>

// Goes to functions

add_action( 'cmb2_admin_init', 'cmb2_sample_metaboxes' );
/**
 * Define the metabox and field configurations.
 */
function cmb2_sample_metaboxes() {

    // Start with an underscore to hide fields from custom fields list
    $prefix = '_siga_';

    /**
     * Initiate the metabox
     */
    $cmb = new_cmb2_box( array(
        'id'            => 'test_metabox',
        'title'         => __( 'Test Metabox', 'cmb2' ),
        'object_types'  => array( 'page', ), // These fields will only show up on pages
        //'show_on'      => array( 'key' => 'page-template', 'value' => 'my-templates/teammembers.php' ), // will show up only on this template
        'context'       => 'normal',
        'priority'      => 'high',
        'show_names'    => true, // Show field names on the left
        // 'cmb_styles' => false, // false to disable the CMB stylesheet
        // 'closed'     => true, // Keep the metabox closed by default
    ) );

    // Regular text field
    $cmb->add_field( array(
        'name'       => __( 'Test Text', 'cmb2' ),
        'desc'       => __( 'Put your text in here)', 'cmb2' ),
        'id'         => $prefix . 'text',
        'type'       => 'text',
        'show_on_cb' => 'cmb2_hide_if_no_cats', // function should return a bool value
		'before_row'   => '<h4 style="color:red;">ALL fields must be populated!</h4>',
        // 'sanitization_cb' => 'my_custom_sanitization', // custom sanitization callback parameter
        // 'escape_cb'       => 'my_custom_escaping',  // custom escaping callback parameter
        // 'on_front'        => false, // Optionally designate a field to wp-admin only
        // 'repeatable'      => true,
    ) );

    // URL text field
    $cmb->add_field( array(
        'name' => __( 'Website URL', 'cmb2' ),
        'desc' => __( 'Add your URL, please', 'cmb2' ),
        'id'   => $prefix . 'url',
        'type' => 'text_url',
        // 'protocols' => array('http', 'https', 'ftp', 'ftps', 'mailto', 'news', 'irc', 'gopher', 'nntp', 'feed', 'telnet'), // Array of allowed protocols
        // 'repeatable' => true,
    ) );

    // Email text field
    $cmb->add_field( array(
        'name' => __( 'Test Text Email', 'cmb2' ),
        'desc' => __( 'Add your email address, please', 'cmb2' ),
        'id'   => $prefix . 'email',
        'type' => 'text_email',
        // 'repeatable' => true,
    ) );

    // Add other metaboxes as needed

}