Dart APIunself_componentUnselfSliverNavigationBarborder border property Null safety Border? border final Implementation final Border? border; unself_component unself_component UnselfSliverNavigationBar border property UnselfSliverNavigationBar class Constructors UnselfSliverNavigationBar Properties automaticallyImplyLeading automaticallyImplyTitle backgroundColor border brightness hashCode heroTag key largeTitle leading middle opaque padding previousPageTitle runtimeType stretch trailing transitionBetweenRoutes Methods createElement createState debugDescribeChildren debugFillProperties noSuchMethod toDiagnosticsNode toString toStringDeep toStringShallow toStringShort Operators operator ==