On the new style Page Tabs, the Like button no longer re-freshes the page. This breaks the existing workflow for "Like-gates", where the signed request is checked on the server. Like the page, page refreshes, boom - the tab now updates to the "Liked" state.
Will there be any kind of event fired when user clicks thew new Like button? Or is this kind of gating no longer possible?
it's a bug that the page is not refreshing after being liked. Here's the bug reported:
https://developers.facebook.com/bugs/228778937218386?browse=search_4f500194bc1bd0293819428
However, I managed to do a workaround to detect if the page is still not using timeline by looking for an album called "Cover Photos" on the album list of that page. Here's a sample:
http://graph.facebook.com/-page_id-/albums?fields=name
You don't need a token unless the page isn't published yet.
The problem with this approach is that some pages still don't have cover picture yet, but it's the minority.
This problem is now fixed by Facebook. See here:
http://developers.facebook.com/bugs/228778937218386
So everyone can relax.
来源：https://stackoverflow.com/questions/9508624/new-timeline-like-button-behavior