Customize Control View appearance in xCode

Question

I'm creating an application for OSX and the only thing I need is to delete the background color of my application's window.

If I run the app, it will appear a window that could be white or black (Aqua, Dark Aqua).

So, i tried to move into the 'ViewController.swift' file and I wrote this code

class ViewController: NSViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        // tell the controller's view to use a CALayer as its backing store
        view.wantsLayer = true
        // change the background color of the layer
        view.layer?.backgroundColor = NSColor.red.cgColor
    }
}

For example, in this way I turn the background colour to red. BUT, this is not what I want. So I tried another way (using RGBA colours)

class ViewController: NSViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        // tell the controller's view to use a CALayer as its backing store
        view.wantsLayer = true
        // change the background color of the layer
        view.layer?.backgroundColor = CGColor(red: 255/255, green: 0/255, blue: 0/255, alpha: 1)
    }
}

And I saw that decreasing the 'alpha' value, the opacity decreases too. So, I tried with

CGColor(red: 255/255, green: 0/255, blue: 0/255, alpha: 0)

The red colour disappears, but now you can see the white (or black) colour of the ViewController.

I understood that I just create another layer (like an ImageView) with a colour, but I haven't modified the ViewController background. Is there a way I can do this? Or it is just impossible?

Answer 1

I've found out the solution. Just go to the "ViewController.swift" file and than write this

class ViewController: NSViewController {

    override func viewWillAppear() {
        super.viewWillAppear()
        view.window?.isOpaque = false
        view.window?.backgroundColor = NSColor(red: 1, green: 0.5, blue: 0.5, alpha: 0.0)
    }
}

If you wanna change the colour, just fix the red, green, blue values. The alpha value determinate the transparency.