CupertinoSliverNavigationBar constructor Null safety

const CupertinoSliverNavigationBar(
  1. {Key? key,
  2. Widget? largeTitle,
  3. Widget? leading,
  4. bool automaticallyImplyLeading = true,
  5. bool automaticallyImplyTitle = true,
  6. String? previousPageTitle,
  7. Widget? middle,
  8. Widget? trailing,
  9. Border? border = _kDefaultNavBarBorder,
  10. Color? backgroundColor,
  11. Brightness? brightness,
  12. EdgeInsetsDirectional? padding,
  13. bool transitionBetweenRoutes = true,
  14. Object heroTag = _defaultHeroTag,
  15. bool stretch = false}
)

Creates a navigation bar for scrolling lists.

The largeTitle argument is required and must not be null.

Implementation

const CupertinoSliverNavigationBar({
  super.key,
  this.largeTitle,
  this.leading,
  this.automaticallyImplyLeading = true,
  this.automaticallyImplyTitle = true,
  this.previousPageTitle,
  this.middle,
  this.trailing,
  this.border = _kDefaultNavBarBorder,
  this.backgroundColor,
  this.brightness,
  this.padding,
  this.transitionBetweenRoutes = true,
  this.heroTag = _defaultHeroTag,
  this.stretch = false,
}) : assert(automaticallyImplyLeading != null),
     assert(automaticallyImplyTitle != null),
     assert(
       automaticallyImplyTitle == true || largeTitle != null,
       'No largeTitle has been provided but automaticallyImplyTitle is also '
       'false. Either provide a largeTitle or set automaticallyImplyTitle to '
       'true.',
     );