copyWith method
Do a copy of the object with other child
Implementation
FlexPersonalizableWidget copyWith(Widget child) {
final flexObject = new FlexPersonalizableWidget(child);
//Complete the grid settings
flexObject.columns = this.columns;
flexObject.columnsLand = this.columnsLand;
flexObject.offsets = this.offsets;
flexObject.offsetsLand = this.offsetsLand;
return flexObject;
}