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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 |
---|---|
4307 | * |
4308 | * @since 4.7.4 |
4309 | * @since 4.8.0 The filter's default value is `true` rather than `null`. |
4310 | * |
4311 | * @link https://core.trac.wordpress.org/ticket/31071 |
4312 | * |
4313 | * @param bool|null $show Whether to show the button, or `null` to decide based |
4314 | * on whether any audio files exist in the media library. |
4315 | */ |
4316 | $show_audio_playlist = apply_filters( 'media_library_show_audio_playlist', true ); |
4317 | if ( null === $show_audio_playlist ) { |
4318 | $show_audio_playlist = $wpdb->get_var( |
4319 | " |
4320 | SELECT ID |
4321 | FROM $wpdb->posts |
4322 | WHERE post_type = 'attachment' |
4323 | AND post_mime_type LIKE 'audio%' |
4324 | LIMIT 1 |
4325 | " |