SnackBar constructor Null safety

const SnackBar(
  1. {Key? key,
  2. required Widget content,
  3. Color? backgroundColor,
  4. double? elevation,
  5. EdgeInsetsGeometry? margin,
  6. EdgeInsetsGeometry? padding,
  7. double? width,
  8. ShapeBorder? shape,
  9. SnackBarBehavior? behavior,
  10. SnackBarAction? action,
  11. Duration duration,
  12. Animation<double>? animation,
  13. VoidCallback? onVisible,
  14. DismissDirection dismissDirection}
)

Creates a snack bar.

The content argument must be non-null. The elevation must be null or non-negative.

Implementation

const SnackBar({
  Key? key,
  required this.content,
  this.backgroundColor,
  this.elevation,
  this.margin,
  this.padding,
  this.width,
  this.shape,
  this.behavior,
  this.action,
  this.duration = _snackBarDisplayDuration,
  this.animation,
  this.onVisible,
  this.dismissDirection = DismissDirection.down,
}) : assert(elevation == null || elevation >= 0.0),
     assert(content != null),
     assert(
       width == null || margin == null,
       'Width and margin can not be used together',
     ),
     assert(duration != null),
     super(key: key);