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<?php
/**
 * Plugin Name: Remove Admin Bar in WordPress 3.3
 * Plugin URI:  http://wordpress.stackexchange.com/questions/40983/removing-admin-bar-from-wordpress-dashboard
 * Description: Remove Admin Bar
 * Version:	1.0.0
 * Author:      Frank Bültge
 * Author URI:  http://bueltge.de
 * License:     GPLv3
 */

// This file is not called from WordPress. We don't like that.
! defined( 'ABSPATH' ) and exit;

add_action( 'init', 'fb_remove_admin_bar', 0 );
function fb_remove_admin_bar() {
	wp_deregister_script( 'admin-bar' );
	wp_deregister_style( 'admin-bar' );
	remove_action( 'init', '_wp_admin_bar_init' );
	remove_action( 'wp_footer', 'wp_admin_bar_render', 1000 );
	remove_action( 'admin_footer', 'wp_admin_bar_render', 1000 );
	// maybe also: 'wp_head'
	foreach ( array( 'wp_head', 'admin_head' ) as $hook ) {
		add_action(
			$hook,
			create_function(
				'',
				"echo '<style>body.admin-bar, body.admin-bar #wpcontent, body.admin-bar #adminmenu {
					 padding-top: 0px !important;
					}
					html.wp-toolbar {
						padding-top: 0px !important;
					}</style>';"
			)
		);
	}
}