ios - 如何在iOS Swift的UIView中的左右和底部设置阴影？

我想在左侧，右侧和底部看到阴影。但是Swift 3阴影偏移仅提供高度或宽度。我发现类似的答案，请参见下面的链接，它显示阴影左上右阴影。我要左右左右。


见链接little similar answer

最佳答案

与提供的链接几乎相同的任务，只需更改BezierPath。

let block1 = UIView(frame: CGRect.init(x: 50, y: 50, width: 300, height: 300))
block1.backgroundColor = UIColor.red

block1.layer.masksToBounds = false
block1.layer.shadowOffset = CGSize(width: 0.0, height: 0.0)
block1.layer.shadowRadius = 5.0
block1.layer.shadowOpacity = 0.7

let path = UIBezierPath()
path.move(to: CGPoint(x: 0.0, y: 0.0))
// Move to center between two top points instead of bottom
path.addLine(to: CGPoint(x: block1.frame.size.width/2.0, y: block1.frame.size.height/2.0))
path.addLine(to: CGPoint(x: block1.frame.size.width, y: 0.0))
path.addLine(to: CGPoint(x: block1.frame.size.width, y: block1.frame.size.height))
path.addLine(to: CGPoint(x: 0.0, y: block1.frame.size.height))
path.close()
block1.layer.shadowPath = path.cgPath