FloatingActionButton constructor

const FloatingActionButton({Key key, Widget child, String tooltip, Color foregroundColor, Color backgroundColor, Object heroTag: const _DefaultHeroTag(), double elevation: 6.0, double highlightElevation: 12.0, @required VoidCallback onPressed, bool mini: false, ShapeBorder shape: const CircleBorder(), Clip clipBehavior: Clip.none, MaterialTapTargetSize materialTapTargetSize, bool isExtended: false })

Creates a circular floating action button.

The elevation, highlightElevation, mini, shape, and clipBehavior arguments must not be null.

Implementation 

const FloatingActionButton({
  Key key,
  this.child,
  this.tooltip,
  this.foregroundColor,
  this.backgroundColor,
  this.heroTag = const _DefaultHeroTag(),
  this.elevation = 6.0,
  this.highlightElevation = 12.0,
  @required this.onPressed,
  this.mini = false,
  this.shape = const CircleBorder(),
  this.clipBehavior = Clip.none,
  this.materialTapTargetSize,
  this.isExtended = false,
}) :  assert(elevation != null),
      assert(highlightElevation != null),
      assert(mini != null),
      assert(shape != null),
      assert(isExtended != null),
      _sizeConstraints = mini ? _kMiniSizeConstraints : _kSizeConstraints,
      super(key: key);