ios - How to add spacing and rounded corners to a tableview? -

ios - How to add spacing and rounded corners to a tableview? -

i'm trying figure out how add together margin tableview. right looks this:

but, this:

i tried insetting, didn't work right. i'm new, not quite sure how cgrect works.

i writing in swift.

try self.tableview.layoutmargins = uiedgeinsetszero

ios uitableview swift