Swift: Switch between NSViewController inside Container View / NSView

Question

I want to achieve a really simple task—changing the ViewController of a Container View by pressing a button:

In my example the ViewController1 is embedded into the Container View using Interface Builder. By pressing the Button ViewController2 I want to change the view to the second ViewController.

I’m confused because the Container View itself seems to be a NSView if I create an Outlet and as far as I know a NSView can’t contain a VC. Really appreciate your help!

Answer 1

Just note that in order for this to work you have to add storyboard identifiers to your view controllers, which can by going to your storyboard then selecting the Identity Inspector in the right hand pane and then entering the Storyboard ID in the Identity subcategory.

Then this implementation of ViewController would achieve what you are looking for.

import Cocoa

class ViewController: NSViewController {

    // link to the NSView Container
    @IBOutlet weak var container : NSView!

    var vc1 : ViewController1!
    var vc2 : ViewController2!

    var vc1Active : Bool = false

    override func viewDidLoad() {
        super.viewDidLoad()

        // Make sure to set your storyboard identiefiers on ViewController1 and ViewController2
        vc1 = NSStoryboard(name: "name", bundle: nil).instantiateController(withIdentifier: "ViewController1") as! ViewController1
        vc2 = NSStoryboard(name: "name", bundle: nil).instantiateController(withIdentifier: "ViewController2") as! ViewController2

        self.addChild(vc1)
        self.addChild(vc2)
        vc1.view.frame = self.container.bounds
        self.container.addSubview(vc1.view)
        vc1Active = true

    }

    // You can link this action to both buttons
    @IBAction func switchViews(sender: NSButton) {

        for sView in self.container.subviews {
            sView.removeFromSuperview()
        }

        if vc1Active == true {

            vc1Active = false
            vc2.view.frame = self.container.bounds
            self.container.addSubview(vc2.view)

        } else {

            vc1Active = true
            vc1.view.frame = self.container.bounds
            self.container.addSubview(vc1.view)
        }

    }
}