Present view controller programmatically from NSWindowController

Question

I am working with swift 4 for macOS and I can show another view controller programmatically with this code:

@IBAction func showVC(_ sender: NSButton) {
    let vc = NSStoryboard(name: NSStoryboard.Name(rawValue: "Main"), bundle: nil).instantiateController(withIdentifier: NSStoryboard.SceneIdentifier(rawValue: "MyVC")) as! NSViewController
    self.presentViewController(vc, asPopoverRelativeTo: sender.bounds, of: sender, preferredEdge: .maxX, behavior: .transient)
}

Now I would like to do the same from a NSWindowController, but I get below "error":

value of type 'WindowController' has no member 'presentViewController'

Is there another way to realize it?

NEXT TRY

   @IBAction func showVC(_ sender: NSToolbarItem) {
    let vc = NSStoryboard(name: NSStoryboard.Name(rawValue: "Main"), bundle: nil).instantiateController(withIdentifier: NSStoryboard.SceneIdentifier(rawValue: "MyVC")) as! NSViewController
self.contentViewController?.presentViewController(x, asPopoverRelativeTo: sender.view!.bounds, of: sender.view!, preferredEdge: .maxX, behavior: .transient)

    }        

the app crashes on the second line with:

fatal error: unexpectedly found nil while unwrapping an Optional value

i check following:

print(sender.view?.bounds ?? "No bounds")
print(sender.view ?? "No view")

Print result

No bounds
No view

But why??

Answer 1

try this :

let storyBoard = NSStoryboard(name: NSStoryboard.Name(rawValue: "Main"), bundle: nil)
let mainViewController : NSViewController = storyBoard.instantiateController(withIdentifier: NSStoryboard.SceneIdentifier(rawValue: "myVC")) as! NSViewController
self.contentViewController!.presentViewController(mainViewController, asPopoverRelativeTo: sender.bounds, of: sender, preferredEdge: .maxY, behavior: .transient)