Dart APIunself_componentResponsiveLayoutBuilderxLarge xLarge property Null safety ResponsiveLayoutWidgetBuilder? xLarge final ResponsiveLayoutWidgetBuilder for xLarge layout. Implementation final ResponsiveLayoutWidgetBuilder? xLarge; unself_component unself_component ResponsiveLayoutBuilder xLarge property ResponsiveLayoutBuilder class Constructors ResponsiveLayoutBuilder Properties child hashCode key large medium runtimeType small xLarge Methods build createElement debugDescribeChildren debugFillProperties noSuchMethod toDiagnosticsNode toString toStringDeep toStringShallow toStringShort Operators operator ==