Need help with grouping in ListGrid

I have extended ListGrid and I am creating ListGrid of my extension type.
After applying group on that list grid, the component is being changed to treegrid. Now if we try to sort that item I am getting record of ListGridRecord instead of my extended record type.

The problem with this is normal ListGridRecord is not having all the attributes that's been set.

Could you please guide me how to resolve this problem?


Thanks in advance