PositionedTransition constructor Null safety

const PositionedTransition(
  1. {Key? key,
  2. required Animation<RelativeRect> rect,
  3. required Widget child}
)

Creates a transition for Positioned.

The rect argument must not be null.

Implementation

const PositionedTransition({
  super.key,
  required Animation<RelativeRect> rect,
  required this.child,
}) : assert(rect != null),
     super(listenable: rect);