Border.symmetric constructor Null safety

const Border.symmetric(
  1. {BorderSide vertical: BorderSide.none,
  2. BorderSide horizontal: BorderSide.none}

Creates a border with symmetrical vertical and horizontal sides.

The vertical argument applies to the left and right sides, and the horizontal argument applies to the top and bottom sides.

All arguments default to BorderSide.none and must not be null.


const Border.symmetric({
  BorderSide vertical = BorderSide.none,
  BorderSide horizontal = BorderSide.none,
}) : assert(vertical != null),
     assert(horizontal != null),
     left = vertical,
     top = horizontal,
     right = vertical,
     bottom = horizontal;