Move NSWindow standardWindowButtons in Swift

buttons.swift

// Add this to your main view.

override func viewDidLayout() {
        
    super.viewDidLayout()

    if let btn = view.window?.standardWindowButton(.closeButton) {
        btn.removeFromSuperview()
        btn.setFrameOrigin(NSPoint(x: 12, y: 28))
        view.addSubview(btn)
    }

    if let btn = view.window?.standardWindowButton(.miniaturizeButton) {
        btn.removeFromSuperview()
        btn.setFrameOrigin(NSPoint(x: 32, y: 28))
        view.addSubview(btn)
    }

    if let btn = view.window?.standardWindowButton(.zoomButton) {
        btn.removeFromSuperview()
        btn.setFrameOrigin(NSPoint(x: 52, y: 28))
        view.addSubview(btn)
    }


}

hi，I use your code with playground,then i put a button to the playground ,when i run the program ,Xcode warn:

2016-08-21 13:37:59.105 airprojectS[5072:144369] Layout still needs update after calling -[NSView layout]. NSView or one of its superclasses may have overridden -layout without calling super. Or, something may have dirtied layout in the middle of updating it. Both are programming errors in Cocoa Autolayout. The former is pretty likely to arise if some pre-Cocoa Autolayout class had a method called layout, but it should be fixed.

can you help me to solve the program? thank u