public function __construct( $args = array() ) {
    $defaults = array(
      'url'    => '',
      'plugin' => '',
      'nonce'  => '',
      'title'  => __( 'Update Plugin' ),
    );
    $args     = wp_parse_args( $args, $defaults );

    $this->plugin = $args['plugin'];

    $this->plugin_active         = is_plugin_active( $this->plugin );
    $this->plugin_network_active = is_plugin_active_for_network( $this->plugin );

    parent::__construct( $args );
  }