Handle State Change

<String> LViS.Powerbar.ON_STATE_CHANGE

Notifies about state change.

Example

// shorthand
var P = window.LViS.Powerbar;

element.bind(P.ON_STATE_CHANGE, function (state) {
    switch (state) {
        case P.STATE_STARTED:
            renderStartedState();
        break;
        case P.STATE_CLOSED:
            renderClosedState();
        break;
    }
});