I was recently asked to implement a comments section using the Facebook API. In general Facebook makes it really easy to do this with only a few lines of Javascript. When I tried to use their comment counting as well, though, I got this error:
this._count.value is undefined
So I looked into it a bit more, and it turns out that the issue is when the Facebook API is called multiple times on the same page. Consider how you initialize the API:
<p style="padding-left: 30px;"><div id="fb-root"></div> <script src="http://connect.facebook.net/en_US/all.js#appId=APP_ID&amp;xfbml=1"></script></p>
By using this multiple times on one page, the ID “fb-root” is included multiple times – so when the Javascript fires, it has an issue with populating the ID, and its behavior becomes erratic. If you happen to find yourself in this situation – either by getting that Javascript error, or by having <fb:comments-count> not working, try searching through your code and make sure that fb-root exists only once.
Hey,
I’m having the same issue and only have fb-root in there once…
Did you manage to figure out any other causes?
Thanks,
–d
I didn’t, no. I assume you also checked that you’re only including all.js once in the page as well?
Hi, here I did not have the rb-root twice, but I had FB.init.
Once I removed FB.init, the page worked well.
Thank you! 🙂
Another reason I’ve found which causes this is to do with
If you specify the ‘href’ attribute like , the href attribute must contain a valid URL.
I output /path-to-page by accident in the href attribute which caused the issue. Replacing it with http://www.mysite.com/path-to-page resolved it.
Ben