斯威夫特 - animateWithDuration完成不好的访问

Question

let downFrame = CGRect(x: 0, y: ScreenSize.height, width: ScreenSize.width, height: ScreenSize.height-Constants.navBarHeight) 

UIView.animateWithDuration(0.3, animations: { 
     self.frame = self.downFrame 
    }, 
    completion: nil) 

Animation move view out of screen. Then crash in comletion

Answer 1

你的代码工作得很好

什么是价值Self.downFrame？