UnconstrainedBox constructor

const UnconstrainedBox({Key key, Widget child, TextDirection textDirection, AlignmentGeometry alignment: Alignment.center, Axis constrainedAxis })

Creates a widget that imposes no constraints on its child, allowing it to render at its "natural" size. If the child overflows the parents constraints, a warning will be given in debug mode.

Implementation 

const UnconstrainedBox({
  Key key,
  Widget child,
  this.textDirection,
  this.alignment = Alignment.center,
  this.constrainedAxis,
}) : assert(alignment != null),
     super(key: key, child: child);