class UIBezierPath : NSObject, NSCopying, NSCoding { ... } ... path.addLineToPoint(CGPoint(x: 100, y: 0)) path.fillWithBlendMode(kCGBlendModeMultiply, alpha: 0.7) 將變成 class UIBezierPath : Object, Copying, Coding { ... } ... path.addLineTo(CGPoint(x: 100, y: 0)) path.fillWith(kCGBlendModeMultiply, alpha: 0.7)