Dart APIunself_componentUnSliverAppBarimplyLeading implyLeading property Null safety bool implyLeading final Implementation final bool implyLeading; unself_component unself_component UnSliverAppBar implyLeading property UnSliverAppBar class Constructors UnSliverAppBar Properties description emoji hashCode implyLeading isCollapseCentered isImmersive key leading runtimeType title trailing Methods createElement createState debugDescribeChildren debugFillProperties noSuchMethod toDiagnosticsNode toString toStringDeep toStringShallow toStringShort Operators operator ==