Twitter API: Tweet Button Callbacks

tweet_button_callback.js

function reward_user( event ) {
    if ( event ) {
        // do something
        alert( 'Tweeted' );
    }
}

window.twttr = (function (d,s,id) {
    var t, js, fjs = d.getElementsByTagName(s)[0];
    if (d.getElementById(id)) return; js=d.createElement(s); js.id=id;
    js.src="//platform.twitter.com/widgets.js"; fjs.parentNode.insertBefore(js, fjs);
    return window.twttr || (t = { _e: [], ready: function(f){ t._e.push(f) } });
    }(document, "script", "twitter-wjs"));

twttr.ready(function (twttr) {
    twttr.events.bind('tweet', reward_user);
});