code: function(key){
              this._configs = this._configs || {};
              var config = this._configs[key];
              
              if (!config || !this._configs.hasOwnProperty(key)) {
                  return null;
              }
              
              return config.getValue();
          }
docs: Returns the current value of the attribute.
  @method get
  @param {String} key The attribute whose value will be returned.
  @return {Any} The current value of the attribute.