Dynamic Custom Fields With Custom Metaboxes - Wordpress

fields.php

//download
$meta_boxes[] =	array(
	'id'         => 'meta_marcas_downloads',
	'title'      => 'Downloads',
	'pages'      => array( 'qd_marcas' ), // Post type
	'context'    => 'normal',
	'priority'   => 'high',
	'show_names' => true, // Show field names on the left
	'fields'     => array(

		array(
		    'id'          => $prefix . 'marcas_downloads',
		    'type'        => 'group',
		    'description' => __( 'Itens de download', 'cmb' ),
		    'options'     => array(
		        'group_title'   => __( 'Arquivo {#}', 'cmb' ), // since version 1.1.4, {#} gets replaced by row number
		        'add_button'    => __( 'Adicionar outro item', 'cmb' ),
		        'remove_button' => __( 'Remover item', 'cmb' ),
		        'sortable'      => true, // beta
		    ),
		    
		    // Fields array works the same, except id's only need to be unique for this group. Prefix is not needed.
		    'fields'      => array(

		        array(
		            'name' => 'Título do arquivo',
		            'description' => '',
		            'id'   => $prefix . 'marcas_downloads_title',
		            'type' => 'text_medium',
		        ),

		        array(
				'name' => 'Upload do arquivo',
				'desc' => '',
				'id'   => $prefix . 'marcas_download_file',
				'type' => 'file',
				'save_id' => true
			),
		    ),
		),
	),
);

single.php

//downloads
$entries_downloads = get_post_meta( get_the_ID(), 'qd_marcas_downloads', true );

foreach( (array) $entries_downloads as $key => $entry ):
	$marcas_downloads_title = $entry['qd_marcas_downloads_title'];
	$marcas_download_file = $entry['qd_marcas_download_file'];
endforeach;