Hi Jeck,
Thank you for your interest in Syncfusion products.
Regret for the delay. Please try using GridBoundColumns collection in GridDataBoundGrid to Show/Hide columns instead of LayoutColumns.
GridBoundColumnsCollection coll;
coll = this.gridDataBoundGrid1.Binder.InternalColumns.Clone() as GridBoundColumnsCollection;
//hiding columns
GridBoundColumnsCollection cool = coll.Clone() as GridBoundColumnsCollection;
cool.RemoveAt(2);
cool.RemoveAt(1);
this.gridDataBoundGrid1.GridBoundColumns = cool;
//showing columns
this.gridDataBoundGrid1.GridBoundColumns = coll;
Please refer the following sample which illustrates the above behavior in GridDataBoundGrid.
http://www.syncfusion.com/uploads/redirect.aspx?&team=support&file=MasterDetailHide1705156286.zipLet me know if you need any further clarifications.
Regards,
Christopher K.