Dart APIunself_styleUnFontWeightextraBold extraBold constant Null safety FontWeight const extraBold FontWeight value of w800 Implementation static const FontWeight extraBold = FontWeight.w800; unself_style unself_style UnFontWeight extraBold constant UnFontWeight class Constructors UnFontWeight Properties hashCode runtimeType Methods noSuchMethod toString Operators operator == Constants black bold extraBold extraLight light medium regular semiBold thin