WP hooks navigation: Home/browse • Actions index • Filters index
To save our bandwidth, we show only a snippet of code around each occurence of the hook. View complete file in SVN (without highlighting).
The best way to understand what a hook does is to look at where it occurs in the source code.
do_action( "hook_name" )apply_filters( "hook_name", "what_to_filter" ).Remember, this hook may occur in more than one file. Moreover, the hook's context may change from version to version.
| Line | Code |
|---|---|
| 3493 | * |
| 3494 | * @since 4.7.4 |
| 3495 | * @since 4.8.0 The filter's default value is `true` rather than `null`. |
| 3496 | * |
| 3497 | * @link https://core.trac.wordpress.org/ticket/31071 |
| 3498 | * |
| 3499 | * @param bool|null Whether to show the button, or `null` to decide based |
| 3500 | * on whether any audio files exist in the media library. |
| 3501 | */ |
| 3502 | $show_audio_playlist = apply_filters( 'media_library_show_audio_playlist', true ); |
| 3503 | if ( null === $show_audio_playlist ) { |
| 3504 | $show_audio_playlist = $wpdb->get_var( |
| 3505 | " |
| 3506 | SELECT ID |
| 3507 | FROM $wpdb->posts |
| 3508 | WHERE post_type = 'attachment' |
| 3509 | AND post_mime_type LIKE 'audio%' |
| 3510 | LIMIT 1 |
| 3511 | " |