Home / admin / Custom metabox listing all audio files from media library
  • How to Custom metabox listing all audio files from media library


    I wrote this for a recent project because a client needed an easy way to attach audio files to the post without custom fields complicating things. Adding this snippet to the functions.php of your wordpress theme will add a metabox to your post editing screen with a select menu containing all audio files. Add the second snippet to display the specified audio URL in your wordpress theme.

    ( click code to copy )

    wordpress snippet : PHP

    	add_action("admin_init", "audio_init");
    	add_action('save_post', 'save_audio_link');
    	function audio_init(){
    		add_meta_box("mp3-audio", "MP3 AUDIO", "audio_link", "post", "normal", "low");
    	function audio_link(){
    		global $post;
    		$custom  = get_post_custom($post->ID);
    		$link    = $custom["link"][0];
    		$count   = 0;
    		echo '<div class="link_header">';
    		$query_audio_args = array(
    			'post_type' => 'attachment',
    			'post_mime_type' =>'audio',
    			'post_status' => 'inherit',
    			'posts_per_page' => -1,
    		$query_audio = new WP_Query( $query_audio_args );
    		$audio = array();
    		echo '<select name="link">';
    		echo '<option class="audio_select">SELECT AUDIO FILE</option>';
    		foreach ( $query_audio->posts as $file) {
    		   if($link == $audio[]= $file->guid){
    		      echo '<option value="'.$audio[]= $file->guid.'" selected="true">'.$audio[]= $file->guid.'</option>';
    		      echo '<option value="'.$audio[]= $file->guid.'">'.$audio[]= $file->guid.'</option>';
    		echo '</select><br /></div>';
    		echo '<p>Selecting an audio file from the above list to attach to this post.</p>';
    		echo '<div class="audio_count"><span>Files:</span> <b>'.$count.'</b></div>';
    	function save_audio_link(){
    		global $post;
    		if (defined('DOING_AUTOSAVE') && DOING_AUTOSAVE){ return $post->ID; }
    		update_post_meta($post->ID, "link", $_POST["link"]);
    	add_action( 'admin_head', 'audio_css' );
    	function audio_css() {
    		echo '<style type="text/css">
    			border-top:solid 1px #e5e5e5;
    			padding:6px 6px 6px 12px;
    			margin:0px -6px -8px -6px;
    			-moz-border-radius:0px 0px 6px 6px;
    			-webkit-border-radius:0px 0px 6px 6px;
    			border-radius:0px 0px 6px 6px;
    		.audio_count span{color:#666;}
    	function audio_file_url(){
    		global $wp_query;
    		$custom = get_post_custom($wp_query->post->ID);
    		echo $custom['link'][0];
    ( click code to copy )

    wordpress snippet : PHP


    ( WordPress codex functions, hooks, in this snippet. )

    posts_per_page, query, admin_head, init, save_post, get_post, get_post_custom, update_post_meta, add_meta_box, add_action, selected, wp,
  • zeb

    Hi Kevin, I have a request which may also relate to this article. I hope you could take a look at it and consider if you could publish an article about it.

    My users use custom fields to attach files such as pdf, word, etc. to their posts. It would be wonderfull if I could make it alittle easier for the readers to understan that this is a file rather than a link to other sites by adding an icon to the left side of the file title automatically.
    For example, a user uploads a pdf file and bellow the content (front-end) there is the files title and a pdf icon beside the title. I usually use Custom Field Template plugin.

    I appreciate your concern.

    • Hi Zeb you can do this type of thing with javascript,

      Works very well.  however ill look into an updated version of this snippet as well.

      • zeb

        Thanks for the reply Kevin.
        As you already have stated, it needs an update. It uses jQuery 1.2.6 which is outdated and I’m not quite sure if it is optimated for WordPress and security issues. It would be kind of you if you could publish an update for this.  


        • Hi Zeb,
          Ill post an update soon, however it does not use JQuery, so that should not be a problem.

  • well, nice tips.Is there any sample site that already success to use your script?

    • Its hard to know because a lot of people like this snippet, but since its an admin snippet it is hard to tell.

  • Apelletier Mtl

    Thanks for your post.
    I have a question : how display file name instead of file url.
    Sorry for my bad english.

    • Hi Anne, You will notice on line 24 & 26 – $file->guid change the second instance on each line or guid to post_title eg:   $file->post_title

      line 24

      echo ‘guid.'” selected=”true”>’.$audio[]= $file->guid.”;

      echo ‘guid.'” selected=”true”>’.$audio[]= $file->post_title.”;

      line 26:
      echo ‘guid.'”>’.$audio[]= $file->guid.”;

      echo ‘guid.'”>’.$audio[]= $file->post_title.”;

      • Anne

        Hie Kevin,
        Thanks a lot for your help !

        • No problem Anne enjoy the wordpress snippets,

  • Doug

    Thank you so much! This is exactly what I needed!

    • Hey Doug, cool  glad you like the snippet.

  • Jen


    First this is brilliant, I think something like this should be part of wordpress’s core functionality.

    I’ve been looking at this too see if I can use it as guide for something I’m doing. I’m wondering if there’s a way to adapt this to show link categories rather than media files? Meta boxes with checks and fields I’m familiar with, but drop downs are new for me, and I’m playing around with get_terms(link_category) but its a bit over me on how to work it into a solution like this.

    Any ideas? If not, that’s alright.


  • Michael Wilhelmsen

    Hi Kevin, could you tell me how I can get the URL to display as an audio shortcode in my theme?