The Facebook SDK for JavaScript doesn’t have any standalone files that need to be downloaded or installed, instead you simply need to include a short piece of regular JavaScript in your HTML that will asynchronously load the SDK into your pages. The async load means that it does not block loading other elements of your page.
The following snippet of code will give the basic version of the SDK where the options are set to their most common defaults. You should insert it directly after the opening <body> tag on each page you want to load it:
<script>
window.fbAsyncInit = function() {
FB.init({
appId : ‘your-app-id’,
autoLogAppEvents : true,
xfbml : true,
version : ‘v3.0’
});
};
(function(d, s, id){
var js, fjs = d.getElementsByTagName(s)[0];
if (d.getElementById(id)) {return;}
js = d.createElement(s); js.id = id;
js.src = “https://connect.facebook.net/en_US/sdk.js”;
fjs.parentNode.insertBefore(js, fjs);
}(document, ‘script’, ‘facebook-jssdk’));
</script>
This code will load and initialize the SDK. You must replace the value in your-app-id with the ID of your own Facebook App.
Changing the Language
In the basic setup snippet, the en_US version of the SDK is initialized, which means that all of the Facebook-generated buttons and plugins used on your site will be in US English. (However, pop-up dialogs generated by Facebook like the Login Dialog will be in the language the person has chosen on Facebook, even if they differ from what you’ve selected.) You can change this language by changing the js.src value in the snippet. Take a look at Localization to see the different locales that can be used. For example, if your site is in Spanish, using the following code to load the SDK will cause all Social Plugins to be rendered in Spanish.
<script>
(function(d, s, id){
var js, fjs = d.getElementsByTagName(s)[0];
if (d.getElementById(id)) return;
js = d.createElement(s); js.id = id;
js.src = “https://connect.facebook.net/es_LA/sdk.js”;
fjs.parentNode.insertBefore(js, fjs);
}(document, ‘script’, ‘facebook-jssdk’));
</script>
Login Status Check
If you set status to true in the FB.init() call, the SDK will attempt to get info about the current user immediately after init. Doing this can reduce the time it takes to check for the state of a logged in user if you’re using Facebook Login, but isn’t useful for pages that only have social plugins on them.
You can use FB.getLoginStatus to get a person’s login state.
Disabling XFBML Parsing
With xfbml set to true, the SDK will parse your page’s DOM to find and initialize any social plugins that have been added using XFBML. If you’re not using social plugins on the page, setting xfbml to false will improve page load times. You can find out more about this by looking at Social Plugins.
Triggering Code when the SDK loads
The function assigned to window.fbAsyncInit is run as soon as the SDK has completed loading. Any code that you want to run after the SDK is loaded should be placed within this function and after the call to FB.init. Any kind of JavaScript can be used here, but any SDK functions must be called after FB.init.
Debugging
To improve performance, the JavaScript SDK is loaded minified. You can also load a debug version of the JavaScript SDK that includes more logging and stricter argument checking as well as being non-minified. To do so, change the js.src value in your loading code to this:
js.src = “https://connect.facebook.net/en_US/sdk/debug.js”;
