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WP_Widget_Archives

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概述

WP_Widget_Archives 是 WordPress 核心类，用于实现归档小部件，显示网站文章的月度归档。它继承自 WP_Widget，提供小部件的创建、设置、更新和输出功能。

关键要点

  • 继承自 WP_Widget，用于创建归档小部件实例。
  • 包含四个主要方法：__construct() 初始化小部件，widget() 输出内容，update() 处理设置更新，form() 输出设置表单。
  • 支持下拉菜单和显示文章计数选项，通过 wp_get_archives() 函数生成归档列表。
  • 使用 WordPress 标准小部件钩子和过滤机制，如 widget_title 过滤器。

代码示例

public function __construct() {
    $widget_ops = array(
        'classname'                   => 'widget_archive',
        'description'                 => __( 'A monthly archive of your site’s Posts.' ),
        'customize_selective_refresh' => true,
        'show_instance_in_rest'       => true,
    );
    parent::__construct( 'archives', __( 'Archives' ), $widget_ops );
}

注意事项

  • 小部件设置包括标题、是否显示文章计数和是否使用下拉菜单，需通过表单和 update 方法处理。
  • 输出内容时需遵循 WordPress 小部件结构，使用 before_widget 和 after_widget 等参数。
  • 自 WordPress 2.8.0 版本引入，确保兼容性时注意版本要求。
📄 原文内容

Core class used to implement the Archives widget.

Description

See also

Methods

Name Description
WP_Widget_Archives::__construct Sets up a new Archives widget instance.
WP_Widget_Archives::form Outputs the settings form for the Archives widget.
WP_Widget_Archives::update Handles updating settings for the current Archives widget instance.
WP_Widget_Archives::widget Outputs the content for the current Archives widget instance.

Source

class WP_Widget_Archives extends WP_Widget {


	/**

	 * Sets up a new Archives widget instance.

	 *

	 * @since 2.8.0

	 */

	public function __construct() {

		$widget_ops = array(

			'classname'                   => 'widget_archive',

			'description'                 => __( 'A monthly archive of your site’s Posts.' ),

			'customize_selective_refresh' => true,

			'show_instance_in_rest'       => true,

		);

		parent::__construct( 'archives', __( 'Archives' ), $widget_ops );

	}


	/**

	 * Outputs the content for the current Archives widget instance.

	 *

	 * @since 2.8.0

	 *

	 * @param array $args     Display arguments including 'before_title', 'after_title',

	 *                        'before_widget', and 'after_widget'.

	 * @param array $instance Settings for the current Archives widget instance.

	 */

	public function widget( $args, $instance ) {

		$default_title = __( 'Archives' );

		$title         = ! empty( $instance['title'] ) ? $instance['title'] : $default_title;


		/** This filter is documented in wp-includes/widgets/class-wp-widget-pages.php */

		$title = apply_filters( 'widget_title', $title, $instance, $this->id_base );


		$count    = ! empty( $instance['count'] ) ? '1' : '0';

		$dropdown = ! empty( $instance['dropdown'] ) ? '1' : '0';


		echo $args['before_widget'];


		if ( $title ) {

			echo $args['before_title'] . $title . $args['after_title'];

		}


		if ( $dropdown ) {

			$dropdown_id = "{$this->id_base}-dropdown-{$this->number}";

			?>

		<label class="screen-reader-text" for="<?php echo esc_attr( $dropdown_id ); ?>"></label>

		<select id="<?php echo esc_attr( $dropdown_id ); ?>" name="archive-dropdown">

			 'monthly',

					'format'          => 'option',

					'show_post_count' => $count,

				),

				$instance

			);


			switch ( $dropdown_args['type'] ) {

				case 'yearly':

					$label = __( 'Select Year' );

					break;

				case 'monthly':

					$label = __( 'Select Month' );

					break;

				case 'daily':

					$label = __( 'Select Day' );

					break;

				case 'weekly':

					$label = __( 'Select Week' );

					break;

				default:

					$label = __( 'Select Post' );

					break;

			}

			?>


			<option value=""></option>


		</select>


<script>

( ( dropdownId ) => {

	const dropdown = document.getElementById( dropdownId );

	function onSelectChange() {

		setTimeout( () => {

			if ( 'escape' === dropdown.dataset.lastkey ) {

				return;

			}

			if ( dropdown.value ) {

				document.location.href = dropdown.value;

			}

		}, 250 );

	}

	function onKeyUp( event ) {

		if ( 'Escape' === event.key ) {

			dropdown.dataset.lastkey = 'escape';

		} else {

			delete dropdown.dataset.lastkey;

		}

	}

	function onClick() {

		delete dropdown.dataset.lastkey;

	}

	dropdown.addEventListener( 'keyup', onKeyUp );

	dropdown.addEventListener( 'click', onClick );

	dropdown.addEventListener( 'change', onSelectChange );

})( <?php echo wp_json_encode( $dropdown_id, JSON_HEX_TAG | JSON_UNESCAPED_SLASHES ); ?> );

</script>

			';

			}

			?>


			<ul>

				 'monthly',

							'show_post_count' => $count,

						),

						$instance

					)

				);

				?>

			</ul>


			';

			}

		}


		echo $args['after_widget'];

	}


	/**

	 * Handles updating settings for the current Archives widget instance.

	 *

	 * @since 2.8.0

	 *

	 * @param array $new_instance New settings for this instance as input by the user via

	 *                            WP_Widget_Archives::form().

	 * @param array $old_instance Old settings for this instance.

	 * @return array Updated settings to save.

	 */

	public function update( $new_instance, $old_instance ) {

		$instance             = $old_instance;

		$new_instance         = wp_parse_args(

			(array) $new_instance,

			array(

				'title'    => '',

				'count'    => 0,

				'dropdown' => '',

			)

		);

		$instance['title']    = sanitize_text_field( $new_instance['title'] );

		$instance['count']    = $new_instance['count'] ? 1 : 0;

		$instance['dropdown'] = $new_instance['dropdown'] ? 1 : 0;


		return $instance;

	}


	/**

	 * Outputs the settings form for the Archives widget.

	 *

	 * @since 2.8.0

	 *

	 * @param array $instance Current settings.

	 */

	public function form( $instance ) {

		$instance = wp_parse_args(

			(array) $instance,

			array(

				'title'    => '',

				'count'    => 0,

				'dropdown' => '',

			)

		);

		?>

		<p>

			<label for="<?php echo $this->get_field_id( 'title' ); ?>"></label>

			<input class="widefat" id="<?php echo $this->get_field_id( 'title' ); ?>" name="<?php echo $this->get_field_name( 'title' ); ?>" type="text" value="<?php echo esc_attr( $instance['title'] ); ?>" />

		</p>

		<p>

			<input class="checkbox" type="checkbox"<?php checked( $instance['dropdown'] ); ?> id="get_field_id( 'dropdown' ); ?>" name="get_field_name( 'dropdown' ); ?>" />

			<label for="<?php echo $this->get_field_id( 'dropdown' ); ?>"></label>

			<br />

			<input class="checkbox" type="checkbox"<?php checked( $instance['count'] ); ?> id="get_field_id( 'count' ); ?>" name="get_field_name( 'count' ); ?>" />

			<label for="<?php echo $this->get_field_id( 'count' ); ?>"></label>

		</p>

		</pre><p class="wporg-dot-link-list"><a href="https://developer.wordpress.org/reference/files/wp-includes/widgets/class-wp-widget-archives.php/">View all references</a> <a href="https://core.trac.wordpress.org/browser/tags/6.9.4/src/wp-includes/widgets/class-wp-widget-archives.php#L17">View on Trac</a> <a href="https://github.com/WordPress/wordpress-develop/blob/6.9.4/src/wp-includes/widgets/class-wp-widget-archives.php#L17-L247">View on GitHub</a></p></section>


		<section class="wp-block-wporg-code-reference-related" data-nosnippet="true"><h2 id="related" class="is-toc-heading wp-block-heading has-heading-5-font-size" tabindex="-1" ><a href="#related">Related</a></h2> <section style="margin-top:var(--wp--preset--spacing--20)" class="wp-block-wporg-code-table" id="uses"><figure class="wp-block-table "><table><thead><tr><th scope="col">Uses</th><th scope="col">Description</th></tr></thead><tbody><tr class=""><td><a href="https://developer.wordpress.org/reference/classes/wp_widget/">WP_Widget</a><code>wp-includes/class-wp-widget.php


Core base class extended to register widgets.

Changelog

Version Description
2.8.0 Introduced.