family and was still in beta at the time this book went to press. The
biggest advantage is that you can use it from an HTML page with no
server-side code required, which can be served up by Facebook either
inside an iFrame-based app or inside an
fb:iframe in a Canvas-based app. This opens
up the possibility of creating apps with really rich Ajax
interactions, which can even run outside of Facebook (provided that
the user is logged into Facebook in another window or tab).
Since there’s no server-side code, there’s nothing for you to download. The first step is to create what’s known as a “channel page” on your server, which uses a library developed by Facebook to enable communications between your site and Facebook without running into cross-domain scripting limitations. Create a page on your site called xd_receiver.html and enter the following HTML into it (you can copy and paste from http://wiki.developers.facebook.com/index.php/Cross_Domain_Communication_Channel):
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Cross-Domain Receiver Page</title> </head> <body> <script src="http://static.ak.facebook.com/js/api_lib/ ...