WP_Widget_Categories

17class WP_Widget_Categories extends WP_Widget {18 19	/**20	 * Sets up a new Categories widget instance.21	 *22	 * @since 2.8.023	 */24	public function __construct() {25		$widget_ops = array(26			'classname'                   => 'widget_categories',27			'description'                 => __( 'A list or dropdown of categories.' ),28			'customize_selective_refresh' => true,29			'show_instance_in_rest'       => true,30		);31		parent::__construct( 'categories', __( 'Categories' ), $widget_ops );32	}33 34	/**35	 * Outputs the content for the current Categories widget instance.36	 *37	 * @since 2.8.038	 * @since 4.2.0 Creates a unique HTML ID for the `<select>` element39	 *              if more than one instance is displayed on the page.40	 *41	 * @param array $args     Display arguments including 'before_title', 'after_title',42	 *                        'before_widget', and 'after_widget'.43	 * @param array $instance Settings for the current Categories widget instance.44	 */45	public function widget( $args, $instance ) {46		static $first_dropdown = true;47 48		$default_title = __( 'Categories' );49		$title         = ! empty( $instance['title'] ) ? $instance['title'] : $default_title;50 51		/** This filter is documented in wp-includes/widgets/class-wp-widget-pages.php */52		$title = apply_filters( 'widget_title', $title, $instance, $this->id_base );53 54		$count        = ! empty( $instance['count'] ) ? '1' : '0';55		$hierarchical = ! empty( $instance['hierarchical'] ) ? '1' : '0';56		$dropdown     = ! empty( $instance['dropdown'] ) ? '1' : '0';57 58		echo $args['before_widget'];59 60		if ( $title ) {61			echo $args['before_title'] . $title . $args['after_title'];62		}63 64		$cat_args = array(65			'orderby'      => 'name',66			'show_count'   => $count,67			'hierarchical' => $hierarchical,68		);69 70		if ( $dropdown ) {71			printf( '<form action="%s" method="get">', esc_url( home_url() ) );72			$dropdown_id    = ( $first_dropdown ) ? 'cat' : "{$this->id_base}-dropdown-{$this->number}";73			$first_dropdown = false;74 75			echo '<label class="screen-reader-text" for="' . esc_attr( $dropdown_id ) . '">' . $title . '</label>';76 77			$cat_args['show_option_none'] = __( 'Select Category' );78			$cat_args['id']               = $dropdown_id;79 80			/**81			 * Filters the arguments for the Categories widget drop-down.82			 *83			 * @since 2.8.084			 * @since 4.9.0 Added the `$instance` parameter.85			 *86			 * @see wp_dropdown_categories()87			 *88			 * @param array $cat_args An array of Categories widget drop-down arguments.89			 * @param array $instance Array of settings for the current widget.90			 */91			wp_dropdown_categories( apply_filters( 'widget_categories_dropdown_args', $cat_args, $instance ) );92 93			echo '</form>';94 95			ob_start();96			?>