  if( newState.title ){
                             this.button.title = newState.title;
                         } else {
                             this.button.removeAttribute('title');
                         }

                         // update classes for animations
                         for(var i=0;i<this._states.length;i++){
                             L.DomUtil.removeClass(this._states[i].icon, this._currentState.stateName + '-active');
                             L.DomUtil.addClass(this._s