Adding post type to the Recent post widget to WordPress 3.4+

gistfile1.aw

<?php
add_action( 'in_widget_form', 'extend_recent_posts_form', 10, 3 );
add_filter( 'widget_update_callback', 'extend_recent_posts_update', 10, 4 );
add_filter( 'widget_title', 'extend_recent_posts_init_query_filter', 10, 3 );
add_filter( 'widget_posts_args', 'extend_recent_posts_query' );


function extend_recent_posts_form( $widget, $return, $instance ) {	
	if( ! is_a( $widget, 'WP_Widget_Recent_Posts' ) ) 
		return;

	echo '<select id="' . $widget->get_field_id('posttype') . '" name="' . $widget->get_field_name('posttype') . '" >';

	$post_types = get_post_types( array( 'show_ui' => true ) ); 
	foreach ( $post_types as $post_type ) {
		if( $post_type == $instance['post_type'] ) {
			echo '<option selected="selected">' . $post_type . '</option>';
		}
		else {
			echo '<option>' . $post_type . '</option>';
		}
	}

	echo '</select>';
}

function extend_recent_posts_update( $instance, $new_instance, $old_instance, $widget ) {
	if( ! is_a( $widget, 'WP_Widget_Recent_Posts' ) ) 
		return $instance;

	$post_type = strip_tags( $new_instance['posttype'] );

	if( post_type_exists( $post_type ) ) {
		$instance['post_type'] = $post_type;
	}

	return $instance;
}

// $title, $instance, $id_base
function extend_recent_posts_init_query_filter( $title ) {
	global $recent_posts_posttype;

	if( func_num_args() >= 3 ) {
		$instance = func_get_arg( 1 );
		$id_base  = func_get_arg( 2 );

		if( isset( $instance['post_type'] ) && 'recent-posts' == $id_base ) {
			$recent_posts_posttype = $instance['post_type'];
		}
	}

	return $title;
}

function extend_recent_posts_query( $vars ) {
	global $recent_posts_posttype;

	if( ! empty( $recent_posts_posttype ) ) {
		$vars['post_type'] = $recent_posts_posttype;
 		$recent_posts_posttype = '';
	}	

	return $vars;
}