Tab in UI not working when integrated in theme

Hi Derek,

I made an export of a layout when OptionTree was a theme plugin. Then I integrated the plugin within the theme and added the theme-options.php in the theme folder. Everything works perfectly except for the Tab function within in the UI. It provided: “Sorry, this function does not exist” . Below an example of the array:

array(
        'id'          => 'programma_blok_2',
        'label'       => __( 'Programma Blok 2', 'FD' ),
        'desc'        => '',
        'std'         => '',
        'type'        => 'tab',
        'section'     => 'programma',
        'rows'        => '',
        'post_type'   => '',
        'taxonomy'    => '',
        'min_max_step'=> '',
        'class'       => 'option_tab',
        'condition'   => '',
        'operator'    => 'and'
      ),

https://wordpress.org/plugins/option-tree/