Undefined Index Notice #7

I'm currently using Easy Digital Download plugin and WP_debug is being set to "true", on checkout page of EDD, I get the following notice:

Notice: Undefined index: post_type in C:\xampp\htdocs\wordpress\wp-content\themes\extensv\metaboxes\init.php on line 45

It refers to dev7_meta_box_framework.php on line 45. Here's the code:

if ( 'page' == $_REQUEST['post_type'] ) {

There is something wrong with the "post type" field but i cant figure out what.