var player = {
setVolume: function() {
$(this).trigger("volumeChanged");
},
addVolumeChangeHandler: function(fn) {
$(this).bind("volumeChanged", fn);
}
};
// add a listener
player.addVolumeChangeHandler(function() {
alert("volume has been changed");
});
// change volume (should fire the attached listener)
player.setVolume(); // alerts "volume has been changed"