SelectionManager = function() {
        this.selectionMap_ = {};
      };
      
      SelectionManager.prototype.select = function(id) {
        this.selectionMap_[id] = id;
        $('#' + id).addClass('ui-selected');
      };
      SelectionManager.prototype.unselect = function(id) {
        delete this.selectionMap_[id];
        $('#' + id).removeClass('ui-selected');
      };