WP_Widget_Pages::widget( array $args, array $instance )

	public function widget( $args, $instance ) {
		$title = ! empty( $instance['title'] ) ? $instance['title'] : __( 'Pages' );

		/**
		 * Filters the widget title.
		 *
		 * @since WP-2.6.0
		 *
		 * @param string $title    The widget title. Default 'Pages'.
		 * @param array  $instance Array of settings for the current widget.
		 * @param mixed  $id_base  The widget ID.
		 */
		$title = apply_filters( 'widget_title', $title, $instance, $this->id_base );

		$sortby = empty( $instance['sortby'] ) ? 'menu_order' : $instance['sortby'];
		$exclude = empty( $instance['exclude'] ) ? '' : $instance['exclude'];

		if ( $sortby == 'menu_order' )
			$sortby = 'menu_order, post_title';

		/**
		 * Filters the arguments for the Pages widget.
		 *
		 * @since WP-2.8.0
		 * @since WP-4.9.0 Added the `$instance` parameter.
		 *
		 * @see wp_list_pages()
		 *
		 * @param array $args     An array of arguments to retrieve the pages list.
		 * @param array $instance Array of settings for the current widget.
		 */
		$out = wp_list_pages( apply_filters( 'widget_pages_args', array(
			'title_li'    => '',
			'echo'        => 0,
			'sort_column' => $sortby,
			'exclude'     => $exclude
		), $instance ) );

		if ( ! empty( $out ) ) {
			echo $args['before_widget'];
			if ( $title ) {
				echo $args['before_title'] . $title . $args['after_title'];
			}
		?>
		<ul>
			<?php echo $out; ?>
		</ul>
		<?php
			echo $args['after_widget'];
		}
	}