I'm trying to figure out how to have a custom background image (instead of plain white TableView) on my app's FirebaseUI login screen, for iOS (Swift).

So far, I've got the code below (from my ViewController.swift file), which presents the image OVER the three login buttons, and I'd like the image to go BEHIND the three buttons for Facebook, Google, and email.

    func login() {

        let authUI = FIRAuthUI.init(auth: FIRAuth.auth()!)

        let options = FIRApp.defaultApp()?.options

        let clientId = options?.clientID

        let googleProvider = FIRGoogleAuthUI(clientID: clientId!)

        let facebookProvider = FIRFacebookAuthUI(appID: kFacebookAppID)

        authUI?.delegate = self

        authUI?.providers = [googleProvider, facebookProvider]

        let authViewController = authUI?.authViewController()


        let width = UIScreen.main.bounds.size.width

        let height = UIScreen.main.bounds.size.height


        let imageViewBackground = UIImageView(frame: CGRect(x: 0, y: 0, width: width, height: height))

        imageViewBackground.image = UIImage(named: "bizzybooksbee")


        // you can change the content mode:

        imageViewBackground.contentMode = UIViewContentMode.scaleAspectFill


        authViewController?.view.insertSubview(imageViewBackground, at: 1)


        self.present(authViewController!, animated: true, completion: nil)


Here's a picture of what the code results in right now. Since my image is partly translucent, you can still see the buttons through the image, and can actually still click on them, too. By the way, this isn't the image I'll be using - it's just temporary.


To see a basic run down of my code, here's a YouTube tutorial I did on how to install the FirebaseUI login solution on iOS.