get midColumnVisible() {
      if (this._columnLayout) {
        return !this._isColumnHidden(this._columnLayout[1]);
      }
      return false;
    }
Returns if the <code>middle</code> column is visible.
@readonly
@type {boolean}
@defaultvalue false
@name sap.ui.webc.fiori.FlexibleColumnLayout.prototype.midColumnVisible
@public