sidebar-selector.php

<?php

/**
 * Sidebar Picker
 */

if ( !class_exists( 'My_Sidebar_Picker' ) ) :

class My_Sidebar_Picker {

	private static $instance;

	private $dynamic_widget_areas;

	private function __construct() {
		/* Don't do anything, needs to be initialized via instance() method */
	}

	public static function instance() {
		if ( ! isset( self::$instance ) ) {
			self::$instance = new My_Sidebar_Picker;
			self::$instance->setup();
		}
		return self::$instance;
	}


	public function setup() {
		add_action( 'save_post', array( $this, 'save_sidebar_link' ) );
		add_action( 'admin_print_styles-post.php', array( $this, 'sidebar_css' ) );
		add_action( 'admin_print_styles-post-new.php', array( $this, 'sidebar_css' ) );
		add_action( 'add_meta_boxes', array( $this, 'add_meta_boxes' ) );

		$this->dynamic_widget_areas = array(
			/* rename or create new dynamic sidebars */
			"Sidebar 01",
			"Sidebar 02",
			"Sidebar 03",
			"Sidebar 04",
			"Sidebar 05",
			"Sidebar 06",
			"Sidebar 07",
			"Search Template",
		);

		if ( function_exists('register_sidebar') ) {
			foreach ( $this->dynamic_widget_areas as $widget_area_name ) {
				register_sidebar( array(
				   'name'=> $widget_area_name,
				   'before_widget' => '<div id="%1$s" class="widget %2$s left half">',
				   'after_widget' => '</div>',
				   'before_title' => '<h3 class="widgettitle">',
				   'after_title' => '</h3>',
				) );
			}
		}
	}


	public function add_meta_boxes() {
		add_meta_box( "sidebar_meta", "Sidebar Selection", array( $this, "sidebar_link" ), "page", "side", "default" );
	}


	public function save_sidebar_link( $post_id ) {
		if ( defined( 'DOING_AUTOSAVE' ) && DOING_AUTOSAVE ) {
			return;
		}

		if ( ! isset( $_POST['some_nonce_field'] ) ) {
			return;
		}

		check_admin_referer( 'some_nonce_key', 'some_nonce_field' );

		if ( in_array( $_POST['link'], $this->dynamic_widget_areas ) ) {
			update_post_meta( $post_id, "_sidebar", $_POST["link"] );
		} else {
			delete_post_meta( $post_id, '_sidebar' );
		}
	}


	public function sidebar_link( $post ) {
		$link = get_post_meta( $post->ID, '_sidebar', true );
		wp_nonce_field( 'some_nonce_key', 'some_nonce_field' );
		?>

		<div class="link_header">
			<select name="link" class="sidebar-selection">
				<option value=''>Select Sidebar</option>
				<option value=''>-----------------------</option>
				<?php foreach ( $this->dynamic_widget_areas as $list ) : ?>
					<option <?php selected( $list, $link ) ?>><?php echo esc_html( $list ); ?></option>
				<?php endforeach ?>
			</select><br />
		</div>
		<p>Select sidebar to use on this page.</p>

		<?php
	}


	public function sidebar_css() {
		echo'
		<style type="text/css">
				.sidebar-selection{width:100%;}
		</style>
		';
	}
}

function My_Sidebar_Picker() {
	return My_Sidebar_Picker::instance();
}
add_action( 'after_setup_theme', 'My_Sidebar_Picker' );

endif;