SwiftUI view modifier that performs action when UIInterfaceOrientation changes

SwiftUI_onInterfaceOrientationChange.swift

import SwiftUI

public extension View {
  /// Perform action when interface orientation of the view changes
  /// - Parameter perform: Action to perform
  /// - Returns: Modified view
  func onInterfaceOrientationChange(perform: @escaping (UIInterfaceOrientation) -> Void) -> some View {
    modifier(OnInterfaceOrientationChangeViewModifier(onChange: perform))
  }
}

private struct OnInterfaceOrientationChangeViewModifier: ViewModifier {
  let onChange: (UIInterfaceOrientation) -> Void

  func body(content: Content) -> some View {
    content.background(OnInterfaceOrientationChangeView(onChange: onChange))
  }
}

private struct OnInterfaceOrientationChangeView: UIViewControllerRepresentable {
  let onChange: (UIInterfaceOrientation) -> Void

  func makeUIViewController(context: Context) -> OnInterfaceOrientationChangeViewController {
    OnInterfaceOrientationChangeViewController(onChange: onChange)
  }

  func updateUIViewController(_ uiViewController: OnInterfaceOrientationChangeViewController, context: Context) {}
}

private final class OnInterfaceOrientationChangeViewController: UIViewController {
  init(onChange: @escaping (UIInterfaceOrientation) -> Void) {
    self.onChange = onChange
    super.init(nibName: nil, bundle: nil)
  }

  required init?(coder: NSCoder) { nil }

  let onChange: (UIInterfaceOrientation) -> Void
  var lastOrientation: UIInterfaceOrientation?

  override func viewWillTransition(to size: CGSize, with coordinator: UIViewControllerTransitionCoordinator) {
    super.viewWillTransition(to: size, with: coordinator)
    perform()
  }

  override func willTransition(to newCollection: UITraitCollection, with coordinator: UIViewControllerTransitionCoordinator) {
    super.willTransition(to: newCollection, with: coordinator)
    perform()
  }

  func perform() {
    guard let orientation = view.window?.windowScene?.interfaceOrientation else { return }
    guard lastOrientation == nil || lastOrientation != orientation else { return }
    lastOrientation = orientation
    onChange(orientation)
  }
}

// MARK: - Example

struct ExampleView: View {
  var body: some View {
    Text("Hello, World")
      .onInterfaceOrientationChange { orientation in
        print("^^^ \(orientation.rawValue)")
      }
  }
}