WordPress Admin Posts Listing: Filter Posts by Post Format

<?php
/*
Plugin Name: admin-filter-by-post-format
Plugin URI: http://en.bainternet.info
Description: answer to How to filter by post-format in admin?
http://wordpress.stackexchange.com/questions/26032/how-to-filter-by-post-format-in-admin
Version: 1.0
Author: Bainternet
Author URI: http://en.bainternet.info
*/
 
add_filter( 'parse_query', 'my_admin_posts_filter' );
add_action( 'restrict_manage_posts', 'ba_admin_posts_filter_restrict_manage_posts_format' );
 
function my_admin_posts_filter( &$query ) {
    global $pagenow;
    if ( is_admin() && $pagenow=='edit.php' && isset($_GET['p_format']) && $_GET['p_format'] != '-1') {
 
            $query->query_vars['tax_query'] = array(array(
            'taxonomy' => 'post_format',
            'field' => 'ID',
            'terms' => array($_GET['p_format'])));
 
    }
}
 
function ba_admin_posts_filter_restrict_manage_posts_format() {
    wp_dropdown_categories(array('taxonomy'=> 'post_format','hide_empty' => 0, 'name' => 'p_format', 'show_option_none' => 'Select Post Format'));
}