NavigationBar constructor Null safety

const NavigationBar(
  1. {Key? key,
  2. Duration? animationDuration,
  3. int selectedIndex,
  4. required List<Widget> destinations,
  5. IntSelectionCallback? onDestinationSelected,
  6. Color? backgroundColor,
  7. double? elevation,
  8. Color? shadowColor,
  9. Color? surfaceTintColor,
  10. Color? indicatorColor,
  11. ShapeBorder? indicatorShape,
  12. double? height,
  13. NavigationDestinationLabelBehavior? labelBehavior}
)

Implementation

const factory NavigationBar(
        {final Key? key,
        final Duration? animationDuration,
        final int selectedIndex,
        required final List<Widget> destinations,
        final IntSelectionCallback? onDestinationSelected,
        final Color? backgroundColor,
        final double? elevation,
        final Color? shadowColor,
        final Color? surfaceTintColor,
        final Color? indicatorColor,
        final ShapeBorder? indicatorShape,
        final double? height,
        final NavigationDestinationLabelBehavior? labelBehavior}) =
    _$NavigationBar;