<para> This is useful for making a detail field span across more than one column E.g. if you had to columns next to each other, UserId and UserName then you could make the UserId column span 2 columns so that it can flow into the space occupied by the UserName column. You would only usually use this if this is a stacked column. </para> <para> A value of -1 indicates that the detail should span across to the right until it meets another detail field. This will only ever be the case if this is a stacked column. </para> <para> A value of zero or 1 indicates that no spanning should occur. </para> <para> Column spanning will only work correctly for left-aligned columns. </para>