LineChart,就使用Core Graphics和QuartzCore框架中的CAShapeLayer绘制.这样执行效率明显比堆砌UIView的方法效率高--占用资源少,执行快. 看看CALayer的定义: class CALayer : NSObject, NSCoding, CAMediaTiming 再看看UIView的定义: class UIView : UIResponder, NSCoding, UIAppearance, NSObjectProtocol, UIAppearan…