code: function (value) {
              if (value && this.controller && this.controller.getDisplayTextFromValue) {
                  return this.controller.getDisplayTextFromValue(this._cfg.prefill);
              } else {
                  return value;
              }
          }
docs: Get the text value that should be prefilled in the widget. It takes a default value that could be anything
  (like dates). For non string objects it delegates the string resolution to the controller.
  @param {Object} value
  @return {String}
  @protected