Hero constructor

const Hero({Key key, @required Object tag, CreateRectTween createRectTween, HeroFlightShuttleBuilder flightShuttleBuilder, TransitionBuilder placeholderBuilder, bool transitionOnUserGestures: false, @required Widget child })

Create a hero.

The tag and child parameters must not be null.

Implementation 

const Hero({
  Key key,
  @required this.tag,
  this.createRectTween,
  this.flightShuttleBuilder,
  this.placeholderBuilder,
  this.transitionOnUserGestures = false,
  @required this.child,
}) : assert(tag != null),
     assert(transitionOnUserGestures != null),
     assert(child != null),
     super(key: key);