function jslive(eventType, elementId, cb) {
    document.addEventListener(eventType, function (event) {
        if (event.target.id === elementId) {
            cb.call(event.target, event);
        }
    });
}

// Params are: event type (click, mouseover etc), element to look for (id or class etc), callback function
jslive("click", ".my-class", function (event) {
    console.log("element fired", event);
});