Question

wp_playlist_shortcode( array $attr )

Builds the Playlist shortcode output.

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description

This implements the functionality of the playlist shortcode for displaying a collection of WordPress audio or video files in a post.

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参数

$attr

(array) (Required) Array of default playlist attributes.

• 'type'
  (string) Type of playlist to display. Accepts 'audio' or 'video'. Default 'audio'.
• 'order'
  (string) Designates ascending or descending order of items in the playlist. Accepts 'ASC', 'DESC'. Default 'ASC'.
• 'orderby'
  (string) Any column, or columns, to sort the playlist. If $ids are passed, this defaults to the order of the $ids array ('post__in'). Otherwise default is 'menu_order ID'.
• 'id'
  (int) If an explicit $ids array is not present, this parameter will determine which attachments are used for the playlist. Default is the current post ID.
• 'ids'
  (array) Create a playlist out of these explicit attachment IDs. If empty, a playlist will be created from all $type attachments of $id. Default empty.
• 'exclude'
  (array) List of specific attachment IDs to exclude from the playlist. Default empty.
• 'style'
  (string) Playlist style to use. Accepts 'light' or 'dark'. Default 'light'.
• 'tracklist'
  (bool) Whether to show or hide the playlist. Default true.
• 'tracknumbers'
  (bool) Whether to show or hide the numbers next to entries in the playlist. Default true.
• 'images'
  (bool) Show or hide the video or audio thumbnail (Featured Image/post thumbnail). Default true.
• 'artists'
  (bool) Whether to show or hide artist name in the playlist. Default true.

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返回值

(string) Playlist output. Empty string if the passed type is unsupported.

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源代码

File: wp-includes/media.php

function wp_playlist_shortcode( $attr ) {
	global $content_width;
	$post = get_post();

	static $instance = 0;
	$instance++;

	if ( ! empty( $attr['ids'] ) ) {
		// 'ids' is explicitly ordered, unless you specify otherwise.
		if ( empty( $attr['orderby'] ) ) {
			$attr['orderby'] = 'post__in';
		}
		$attr['include'] = $attr['ids'];
	}

	/**
	 * Filters the playlist output.
	 *
	 * Passing a non-empty value to the filter will short-circuit generation
	 * of the default playlist output, returning the passed value instead.
	 *
	 * @since 3.9.0
	 * @since 4.2.0 The `$instance` parameter was added.
	 *
	 * @param string $output   Playlist output. Default empty.
	 * @param array  $attr     An array of shortcode attributes.
	 * @param int    $instance Unique numeric ID of this playlist shortcode instance.
	 */
	$output = apply_filters( 'post_playlist', '', $attr, $instance );
	if ( $output != '' ) {
		return $output;
	}

	$atts = shortcode_atts( array(
		'type'		=> 'audio',
		'order'		=> 'ASC',
		'orderby'	=> 'menu_order ID',
		'id'		=> $post ? $post->ID : 0,
		'include'	=> '',
		'exclude'   => '',
		'style'		=> 'light',
		'tracklist' => true,
		'tracknumbers' => true,
		'images'	=> true,
		'artists'	=> true
	), $attr, 'playlist' );

	$id = intval( $atts['id'] );

	if ( $atts['type'] !== 'audio' ) {
		$atts['type'] = 'video';
	}

	$args = array(
		'post_status' => 'inherit',
		'post_type' => 'attachment',
		'post_mime_type' => $atts['type'],
		'order' => $atts['order'],
		'orderby' => $atts['orderby']
	);

	if ( ! empty( $atts['include'] ) ) {
		$args['include'] = $atts['include'];
		$_attachments = get_posts( $args );

		$attachments = array();
		foreach ( $_attachments as $key => $val ) {
			$attachments[$val->ID] = $_attachments[$key];
		}
	} elseif ( ! empty( $atts['exclude'] ) ) {
		$args['post_parent'] = $id;
		$args['exclude'] = $atts['exclude'];
		$attachments = get_children( $args );
	} else {
		$args['post_parent'] = $id;
		$attachments = get_children( $args );
	}

	if ( empty( $attachments ) ) {
		return '';
	}

	if ( is_feed() ) {
		$output = "\n";
		foreach ( $attachments as $att_id => $attachment ) {
			$output .= wp_get_attachment_link( $att_id ) . "\n";
		}
		return $output;
	}

	$outer = 22; // default padding and border of wrapper

	$default_width = 640;
	$default_height = 360;

	$theme_width = empty( $content_width ) ? $default_width : ( $content_width - $outer );
	$theme_height = empty( $content_width ) ? $default_height : round( ( $default_height * $theme_width ) / $default_width );

	$data = array(
		'type' => $atts['type'],
		// don't pass strings to JSON, will be truthy in JS
		'tracklist' => wp_validate_boolean( $atts['tracklist'] ),
		'tracknumbers' => wp_validate_boolean( $atts['tracknumbers'] ),
		'images' => wp_validate_boolean( $atts['images'] ),
		'artists' => wp_validate_boolean( $atts['artists'] ),
	);

	$tracks = array();
	foreach ( $attachments as $attachment ) {
		$url = wp_get_attachment_url( $attachment->ID );
		$ftype = wp_check_filetype( $url, wp_get_mime_types() );
		$track = array(
			'src' => $url,
			'type' => $ftype['type'],
			'title' => $attachment->post_title,
			'caption' => $attachment->post_excerpt,
			'description' => $attachment->post_content
		);

		$track['meta'] = array();
		$meta = wp_get_attachment_metadata( $attachment->ID );
		if ( ! empty( $meta ) ) {

			foreach ( wp_get_attachment_id3_keys( $attachment ) as $key => $label ) {
				if ( ! empty( $meta[ $key ] ) ) {
					$track['meta'][ $key ] = $meta[ $key ];
				}
			}

			if ( 'video' === $atts['type'] ) {
				if ( ! empty( $meta['width'] ) && ! empty( $meta['height'] ) ) {
					$width = $meta['width'];
					$height = $meta['height'];
					$theme_height = round( ( $height * $theme_width ) / $width );
				} else {
					$width = $default_width;
					$height = $default_height;
				}

				$track['dimensions'] = array(
					'original' => compact( 'width', 'height' ),
					'resized' => array(
'width' => $theme_width,
'height' => $theme_height
					)
				);
			}
		}

		if ( $atts['images'] ) {
			$thumb_id = get_post_thumbnail_id( $attachment->ID );
			if ( ! empty( $thumb_id ) ) {
				list( $src, $width, $height ) = wp_get_attachment_image_src( $thumb_id, 'full' );
				$track['image'] = compact( 'src', 'width', 'height' );
				list( $src, $width, $height ) = wp_get_attachment_image_src( $thumb_id, 'thumbnail' );
				$track['thumb'] = compact( 'src', 'width', 'height' );
			} else {
				$src = wp_mime_type_icon( $attachment->ID );
				$width = 48;
				$height = 64;
				$track['image'] = compact( 'src', 'width', 'height' );
				$track['thumb'] = compact( 'src', 'width', 'height' );
			}
		}

		$tracks[] = $track;
	}
	$data['tracks'] = $tracks;

	$safe_type = esc_attr( $atts['type'] );
	$safe_style = esc_attr( $atts['style'] );

	ob_start();

	if ( 1 === $instance ) {
		/**
		 * Prints and enqueues playlist scripts, styles, and JavaScript templates.
		 *
		 * @since 3.9.0
		 *
		 * @param string $type  Type of playlist. Possible values are 'audio' or 'video'.
		 * @param string $style The 'theme' for the playlist. Core provides 'light' and 'dark'.
		 */
		do_action( 'wp_playlist_scripts', $atts['type'], $atts['style'] );
	} ?>
<div class="wp-playlist wp-<?php echo $safe_type ?>-playlist wp-playlist-<?php echo $safe_style ?>">
	<?php if ( 'audio' === $atts['type'] ): ?>
	<div class="wp-playlist-current-item"></div>
	<?php endif ?>
	<<?php echo $safe_type ?> controls="controls" preload="none" width="<?php
		echo (int) $theme_width;
	?>"<?php if ( 'video' === $safe_type ):
		echo ' height="', (int) $theme_height, '"';
	endif; ?>></<?php echo $safe_type ?>>
	<div class="wp-playlist-next"></div>
	<div class="wp-playlist-prev"></div>
	<noscript>
	<ol><?php
	foreach ( $attachments as $att_id => $attachment ) {
		printf( '<li>%s</li>', wp_get_attachment_link( $att_id ) );
	}
	?></ol>
	</noscript>
	<script type="application/json" class="wp-playlist-script"><?php echo wp_json_encode( $data ) ?></script>
</div>
	<?php
	return ob_get_clean();
}

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更新日志

Version	description
3.9.0	Introduced.

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相关函数

Uses

• wp-includes/post.php: get_children()
• wp-includes/functions.php: wp_json_encode()
• wp-includes/functions.php: wp_validate_boolean()
• wp-includes/formatting.php: esc_attr()
• wp-includes/query.php: is_feed()
• wp-includes/functions.php: wp_check_filetype()
• wp-includes/functions.php: wp_get_mime_types()
• wp-includes/shortcodes.php: shortcode_atts()
• wp-includes/plugin.php: apply_filters()
• wp-includes/plugin.php: do_action()
• wp-includes/post-thumbnail-template.php: get_post_thumbnail_id()
• wp-includes/post-template.php: wp_get_attachment_link()
• wp-includes/media.php: wp_get_attachment_id3_keys()
• wp-includes/media.php: post_playlist
• wp-includes/media.php: wp_playlist_scripts
• wp-includes/media.php: wp_get_attachment_image_src()
• wp-includes/post.php: wp_mime_type_icon()
• wp-includes/post.php: wp_get_attachment_url()
• wp-includes/post.php: wp_get_attachment_metadata()
• wp-includes/post.php: get_posts()
• wp-includes/post.php: get_post()
Show 16 more uses Hide more uses

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User Contributed Notes

1. Skip to note content You must log in to vote on the helpfulness of this noteVote results for this note: 0You must log in to vote on the helpfulness of this note Contributed by David

   FEEDBACK: This (and other) code references would be quite a bit more useful if they could include SCREEN SHOTS of what the resulting page looks like, where applicable.

   In this case, four screenshots of PLAYLIST results would be appropriate:

   – type=”audio” style=”light” (default)
   – type=”audio” style=”dark”
   – type=”video” (style=”light” – default)
   – type=”video” style=”dark”

   and other screenshots as needed to illustrate the results of various parameters.

   NOTE: These would also be extremely useful on corresponding SHORTCODE pages of the codex.