BottomSheet({Key key, AnimationController animationController, VoidCallback onClosing, WidgetBuilder builder })

Creates a bottom sheet.

Typically, bottom sheets are created implicitly by Scaffold.showBottomSheet, for persistent bottom sheets, or by showModalBottomSheet, for modal bottom sheets.

Source 

BottomSheet({
  Key key,
  this.animationController,
  this.onClosing,
  this.builder
}) : super(key: key) {
  assert(onClosing != null);
  assert(builder != null);
}