外形與UIView的三角形由CAShapeLayer

Question

從教程支持：http://swiftiostutorials.com/tutorial-draw-nice-triangle-view-border-cashapelayer/，我成功地創造出像一個三角形：

class Triangle: UIView { 
    override func drawRect(rect: CGRect) { 
     let mask = CAShapeLayer() 
     mask.frame = self.layer.bounds 

     let width = self.layer.frame.size.width 
     let height = self.layer.frame.size.height 

     let path = CGPathCreateMutable() 

     CGPathMoveToPoint(path, nil, 0, 0) 
     CGPathAddLineToPoint(path, nil, width, 0) 
     CGPathAddLineToPoint(path, nil, width, height) 
     CGPathAddLineToPoint(path, nil, width/2, height) 
     CGPathAddLineToPoint(path, nil, width, height) 


     mask.path = path 
     self.layer.mask = mask 
    } 
} 

但我想要實現的，是像一個三角形：

怎樣才能做到這一點？

Answer 1

使用此路徑，而不是：

CGPathMoveToPoint(path, nil, 0, 0) 
CGPathAddLineToPoint(path, nil, width, 0) 
CGPathAddLineToPoint(path, nil, width/2, height) 
CGPathAddLineToPoint(path, nil, 0, 0) 

滿級：

class Triangle: UIView { 
    override func drawRect(rect: CGRect) { 
     let mask = CAShapeLayer() 
     mask.frame = self.layer.bounds 

     let width = self.layer.frame.size.width 
     let height = self.layer.frame.size.height 

     let path = CGPathCreateMutable() 

     CGPathMoveToPoint(path, nil, 0, 0) 
     CGPathAddLineToPoint(path, nil, width, 0) 
     CGPathAddLineToPoint(path, nil, width/2, height) 
     CGPathAddLineToPoint(path, nil, 0, 0) 

     mask.path = path 
     self.layer.mask = mask 
    } 
}