How to detect transition to landscape when you have more then one viewcontroller

Question

I have a small app with only 4 view controllers and I want to change the layout when the user transitions to/from landscape. I figured out how to check for landscape, but the function lives in one viewController class and I am not clear how to get my other viewControllers to take action when the viewWillTransition fires. Do I put a version of that override function in each view controller class to do things specific to it? When I tried putting the override in both classes after a segue they BOTH fired and didn't feel like "right way to do it" and so I wanted to ask the experts.

Using the code below on app start I set a global bool for whether it is in landscape and I use viewWillTransition to detect changes.

    override func viewWillTransition(to size: CGSize, with coordinator: UIViewControllerTransitionCoordinator) {
    super.viewWillTransition(to: size, with: coordinator)
    print("Will Transition to size \(size) from super view size \(self.view.frame.size)")

    if (size.width > self.view.frame.size.width) {
        print("Landscape")
        inLandscapeMode = true
    } else {
        print("Portrait")
        inLandscapeMode = false
    }

    if (size.width != self.view.frame.size.width) {
        DispatchQueue.main.async {
            // DO SOMETHING LIKE reload a Table/Collection view to ensure no dequeued cells have old constraints... self.tableView.reloadData()
        }
    }
}
func setUpFormatting(){
    let size = UIScreen.main.bounds.size
    print("On App Start size \(size)")
    if size.width > size.height {
        print("Landscape")
        inLandscapeMode = true
    } else {
        print("Portrait")
        inLandscapeMode = false
    }
}

All of

Answer 1

You can get the device orientation in every view controller and setup views by that value

if UIDevice.current.orientation == .portrait {

} else if UIDevice.current.orientation == .landscapeLeft || UIDevice.current.orientation == .landscapeRight {

}