Using custom shadow path on NSView

Question

Unfortunately it seems that setting the shadow attributes on the layer directly doesn't work:

let shadowView = NSView(frame: CGRect(x: 0, y: 0, width: 100, height: 100))
shadowView.wantsLayer = true
shadowView.layer!.backgroundColor = .white
shadowView.layer!.shadowRadius = 50
shadowView.layer!.shadowColor = .black
shadowView.layer!.shadowOffset = CGSize(width: 0, height: -30)
shadowView.layer!.shadowPath = CGPath(roundedRect: shadowView.bounds, cornerWidth: 25, cornerHeight: 25, transform: nil)

Setting the NSView.shadow property instead works:

let shadowView = NSView(frame: CGRect(x: 0, y: 0, width: 100, height: 100))let shadow = NSShadow()
shadow.shadowBlurRadius = 50
shadow.shadowColor = .black
shadow.shadowOffset = CGSize(width: 0, height: -30)
shadowView.shadow = shadow
shadowView.wantsLayer = true
shadowView.layer!.backgroundColor = .white

But NSShadow doesn't support a custom path. What's the easiest way to set a shadow with a custom path?

Answer 1

Edited Answer - after comments...

The reason your shadow code didn't seem to work was because you were missing two property settings:

// need these two properties set
shadowView.layer!.masksToBounds = false
shadowView.layer!.shadowOpacity = 1.0

Quick example (I moved the shadowView origin to 100,100 so we can see the full shadow):

class ViewController: NSViewController {
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        let shadowView = NSView(frame: CGRect(x: 100, y: 100, width: 100, height: 100))
        view.addSubview(shadowView)
        
        shadowView.wantsLayer = true
        
        shadowView.layer!.backgroundColor = .white
        shadowView.layer!.shadowRadius = 50
        shadowView.layer!.shadowColor = .black
        shadowView.layer!.shadowOffset = CGSize(width: 0, height: -30)
        shadowView.layer!.shadowPath = CGPath(roundedRect: shadowView.bounds, cornerWidth: 25, cornerHeight: 25, transform: nil)
        
        // need these two properties set
        shadowView.layer!.masksToBounds = false
        shadowView.layer!.shadowOpacity = 1.0  // set as desired
        
    }
    
}

Result: