从其他类Swift访问UI对象的属性

Question

I have this class in Swift 2.0:

class CharacterSelectionController: UIViewController {
    @IBOutlet weak var scrollView: UIScrollView!
    @IBOutlet weak var scnView: SCNView!

    var characterArray = [CharacterInfo]()
    var scene: CharacterScene!

    override func viewDidLoad() {

        // Set up the SCNView
        scnView.backgroundColor = AppDelegate().lightBlueColor()
        scnView.showsStatistics = false
        scnView.antialiasingMode = SCNAntialiasingMode.Multisampling2X
        scnView.overlaySKScene = SKScene(size: view.bounds.size)
        scnView.playing = false

       // Start playing the scene
      scnView.scene = scene
      scnView.scene!.rootNode.hidden = false
      scnView.play(self)

In the AppDelegate and other classes I have to set scnView to pause, something like scnView.pause(self). However I cannot seem to be able to access either the view or the self part in the other class. I tried setting some struct in this way:

struct GlobalVariables {
    static var globalGameView: SCNView = SCNView()
}

and then setting globalGameView = scnView but It doesn't work. I also tried:

    var myCustomViewController: CharacterSelectionController = CharacterSelectionController(nibName: nil, bundle: nil)
    myCustomViewController.scnView.pause(myCustomViewController)
    print(myCustomViewController.scnView)

but the app crashes... Any ideas?

Answer 1

You should not try to access another view controller's view objects. That is a violation of the encapsulation principle of object-oriented design. Treat another view controller's views as private.

What you should do is to add a public method to the other view controller that does the changes for you, and the call that method. That way, if you decide to switch your view controller to draw its contents using Metal instead of SceneKit at some future date, you can do that and only your one view controller has to change.