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WP_Widget_Media_Audio

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概述

WP_Widget_Media_Audio 是 WordPress 核心类，用于实现音频小部件，继承自 WP_Widget_Media。它提供音频播放器功能，支持前端渲染、媒体管理和管理界面脚本加载。

关键要点

  • 继承自 WP_Widget_Media，专门处理音频媒体类型。
  • 构造函数设置小部件 ID、标题和描述，并定义本地化字符串。
  • get_instance_schema 方法定义小部件实例的属性模式，包括预加载、循环和音频扩展 URL。
  • render_media 方法在前端渲染音频，使用 wp_audio_shortcode 生成播放器。
  • enqueue_preview_scripts 和 enqueue_admin_scripts 方法分别用于预览和管理界面的脚本和样式加载。
  • render_control_template_scripts 方法渲染表单模板脚本。

代码示例

// 构造函数示例
public function __construct() {
    parent::__construct(
        'media_audio',
        __( 'Audio' ),
        array(
            'description' => __( 'Displays an audio player.' ),
            'mime_type'   => 'audio',
        )
    );
    // 本地化字符串设置
    $this->l10n = array_merge( $this->l10n, array( /* ... */ ) );
}

// get_instance_schema 方法示例
public function get_instance_schema() {
    $schema = array(
        'preload' => array(
            'type'        => 'string',
            'enum'        => array( 'none', 'auto', 'metadata' ),
            'default'     => 'none',
            'description' => __( 'Preload' ),
        ),
        'loop'    => array(
            'type'        => 'boolean',
            'default'     => false,
            'description' => __( 'Loop' ),
        ),
    );
    // 添加音频扩展 URL 模式
    foreach ( wp_get_audio_extensions() as $audio_extension ) {
        $schema[ $audio_extension ] = array(
            'type'        => 'string',
            'default'     => '',
            'format'      => 'uri',
            'description' => sprintf( __( 'URL to the %s audio source file' ), $audio_extension ),
        );
    }
    return array_merge( $schema, parent::get_instance_schema() );
}

// render_media 方法示例
public function render_media( $instance ) {
    $instance = array_merge( wp_list_pluck( $this->get_instance_schema(), 'default' ), $instance );
    $attachment = null;
    if ( $this->is_attachment_with_mime_type( $instance['attachment_id'], $this->widget_options['mime_type'] ) ) {
        $attachment = get_post( $instance['attachment_id'] );
    }
    if ( $attachment ) {
        $src = wp_get_attachment_url( $attachment->ID );
    } else {
        $src = $instance['url'];
    }
    echo wp_audio_shortcode( array_merge( $instance, compact( 'src' ) ) );
}

注意事项

  • 该类自 WordPress 4.8.0 版本引入，使用时需确保版本兼容性。
  • 音频小部件依赖于 MediaElement.js 库，需通过 enqueue_preview_scripts 和 enqueue_admin_scripts 正确加载相关脚本和样式。
  • get_instance_schema 方法返回的模式用于 REST API 和小部件实例验证，开发者可扩展或修改。
  • render_media 方法优先使用附件 ID，若不存在则回退到 URL，确保音频源正确。
📄 原文内容

Core class that implements an audio widget.

Description

See also

Methods

Name Description
WP_Widget_Media_Audio::__construct Constructor.
WP_Widget_Media_Audio::enqueue_admin_scripts Loads the required media files for the media manager and scripts for media widgets.
WP_Widget_Media_Audio::enqueue_preview_scripts Enqueue preview scripts.
WP_Widget_Media_Audio::get_instance_schema Get schema for properties of a widget instance (item).
WP_Widget_Media_Audio::render_control_template_scripts Render form template scripts.
WP_Widget_Media_Audio::render_media Render the media on the frontend.

Source

class WP_Widget_Media_Audio extends WP_Widget_Media {


	/**

	 * Constructor.

	 *

	 * @since 4.8.0

	 */

	public function __construct() {

		parent::__construct(

			'media_audio',

			__( 'Audio' ),

			array(

				'description' => __( 'Displays an audio player.' ),

				'mime_type'   => 'audio',

			)

		);


		$this->l10n = array_merge(

			$this->l10n,

			array(

				'no_media_selected'          => __( 'No audio selected' ),

				'add_media'                  => _x( 'Add Audio', 'label for button in the audio widget' ),

				'replace_media'              => _x( 'Replace Audio', 'label for button in the audio widget; should preferably not be longer than ~13 characters long' ),

				'edit_media'                 => _x( 'Edit Audio', 'label for button in the audio widget; should preferably not be longer than ~13 characters long' ),

				'missing_attachment'         => sprintf(

					/* translators: %s: URL to media library. */

					__( 'That audio file cannot be found. Check your <a href="%s">media library</a> and make sure it was not deleted.' ),

					esc_url( admin_url( 'upload.php' ) )

				),

				/* translators: %d: Widget count. */

				'media_library_state_multi'  => _n_noop( 'Audio Widget (%d)', 'Audio Widget (%d)' ),

				'media_library_state_single' => __( 'Audio Widget' ),

				'unsupported_file_type'      => __( 'Looks like this is not the correct kind of file. Please link to an audio file instead.' ),

			)

		);

	}


	/**

	 * Get schema for properties of a widget instance (item).

	 *

	 * @since 4.8.0

	 *

	 * @see WP_REST_Controller::get_item_schema()

	 * @see WP_REST_Controller::get_additional_fields()

	 * @link https://core.trac.wordpress.org/ticket/35574

	 *

	 * @return array Schema for properties.

	 */

	public function get_instance_schema() {

		$schema = array(

			'preload' => array(

				'type'        => 'string',

				'enum'        => array( 'none', 'auto', 'metadata' ),

				'default'     => 'none',

				'description' => __( 'Preload' ),

			),

			'loop'    => array(

				'type'        => 'boolean',

				'default'     => false,

				'description' => __( 'Loop' ),

			),

		);


		foreach ( wp_get_audio_extensions() as $audio_extension ) {

			$schema[ $audio_extension ] = array(

				'type'        => 'string',

				'default'     => '',

				'format'      => 'uri',

				/* translators: %s: Audio extension. */

				'description' => sprintf( __( 'URL to the %s audio source file' ), $audio_extension ),

			);

		}


		return array_merge( $schema, parent::get_instance_schema() );

	}


	/**

	 * Render the media on the frontend.

	 *

	 * @since 4.8.0

	 *

	 * @param array $instance Widget instance props.

	 */

	public function render_media( $instance ) {

		$instance   = array_merge( wp_list_pluck( $this->get_instance_schema(), 'default' ), $instance );

		$attachment = null;


		if ( $this->is_attachment_with_mime_type( $instance['attachment_id'], $this->widget_options['mime_type'] ) ) {

			$attachment = get_post( $instance['attachment_id'] );

		}


		if ( $attachment ) {

			$src = wp_get_attachment_url( $attachment->ID );

		} else {

			$src = $instance['url'];

		}


		echo wp_audio_shortcode(

			array_merge(

				$instance,

				compact( 'src' )

			)

		);

	}


	/**

	 * Enqueue preview scripts.

	 *

	 * These scripts normally are enqueued just-in-time when an audio shortcode is used.

	 * In the customizer, however, widgets can be dynamically added and rendered via

	 * selective refresh, and so it is important to unconditionally enqueue them in

	 * case a widget does get added.

	 *

	 * @since 4.8.0

	 */

	public function enqueue_preview_scripts() {

		/** This filter is documented in wp-includes/media.php */

		if ( 'mediaelement' === apply_filters( 'wp_audio_shortcode_library', 'mediaelement' ) ) {

			wp_enqueue_style( 'wp-mediaelement' );

			wp_enqueue_script( 'wp-mediaelement' );

		}

	}


	/**

	 * Loads the required media files for the media manager and scripts for media widgets.

	 *

	 * @since 4.8.0

	 */

	public function enqueue_admin_scripts() {

		parent::enqueue_admin_scripts();


		wp_enqueue_style( 'wp-mediaelement' );

		wp_enqueue_script( 'wp-mediaelement' );


		$handle = 'media-audio-widget';

		wp_enqueue_script( $handle );


		$exported_schema = array();

		foreach ( $this->get_instance_schema() as $field => $field_schema ) {

			$exported_schema[ $field ] = wp_array_slice_assoc( $field_schema, array( 'type', 'default', 'enum', 'minimum', 'format', 'media_prop', 'should_preview_update' ) );

		}

		wp_add_inline_script(

			$handle,

			sprintf(

				'wp.mediaWidgets.modelConstructors[ %s ].prototype.schema = %s;',

				wp_json_encode( $this->id_base, JSON_HEX_TAG | JSON_UNESCAPED_SLASHES ),

				wp_json_encode( $exported_schema, JSON_HEX_TAG | JSON_UNESCAPED_SLASHES )

			)

		);


		wp_add_inline_script(

			$handle,

			sprintf(

				'

					wp.mediaWidgets.controlConstructors[ %1$s ].prototype.mime_type = %2$s;

					wp.mediaWidgets.controlConstructors[ %1$s ].prototype.l10n = _.extend( {}, wp.mediaWidgets.controlConstructors[ %1$s ].prototype.l10n, %3$s );

				',

				wp_json_encode( $this->id_base, JSON_HEX_TAG | JSON_UNESCAPED_SLASHES ),

				wp_json_encode( $this->widget_options['mime_type'], JSON_HEX_TAG | JSON_UNESCAPED_SLASHES ),

				wp_json_encode( $this->l10n, JSON_HEX_TAG | JSON_UNESCAPED_SLASHES )

			)

		);

	}


	/**

	 * Render form template scripts.

	 *

	 * @since 4.8.0

	 */

	public function render_control_template_scripts() {

		parent::render_control_template_scripts()

		?>

		<script type="text/html" id="tmpl-wp-media-widget-audio-preview">

			<# if ( data.error && 'missing_attachment' === data.error ) { #>

				<?php

				wp_admin_notice(

					$this->l10n['missing_attachment'],

					array(

						'type'               => 'error',

						'additional_classes' => array( 'notice-alt', 'notice-missing-attachment' ),

					)

				);

				?>

			<# } else if ( data.error ) { #>

				<?php

				wp_admin_notice(

					__( 'Unable to preview media due to an unknown error.' ),

					array(

						'type'               => 'error',

						'additional_classes' => array( 'notice-alt' ),

					)

				);

				?>

			<# } else if ( data.model && data.model.src ) { #>

				<?php wp_underscore_audio_template(); ?>

			<# } #>

		</script>

		</pre><p class="wporg-dot-link-list"><a href="https://developer.wordpress.org/reference/files/wp-includes/widgets/class-wp-widget-media-audio.php/">View all references</a> <a href="https://core.trac.wordpress.org/browser/tags/6.9.4/src/wp-includes/widgets/class-wp-widget-media-audio.php#L18">View on Trac</a> <a href="https://github.com/WordPress/wordpress-develop/blob/6.9.4/src/wp-includes/widgets/class-wp-widget-media-audio.php#L18-L217">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_media/">WP_Widget_Media</a><code>wp-includes/widgets/class-wp-widget-media.php


Core class that implements a media widget.

Changelog

Version Description
4.8.0 Introduced.