ios – SwiftUI views lock-up after background and sleep for “Designed for iPad” apps

There’s an simply reproducible SwiftUI bug on macOS the place an app’s UI state now not updates/re-renders for “Designed for iPad” apps (i.e. ProcessInfo.processInfo.isiOSAppOnMac == true). The bug happens in Xcode and likewise if the app is working impartial of Xcode.

The bug happens when:

1. the person Hides the app (i.e. it goes into the background)
2. the person places the Mac to sleep (e.g. Apple menu > Sleep)
3. a complete of ~60 seconds transpires (i.e. macOS places the app into the “suspended state”)
4. when the app is introduced again into the foreground the UI now not updates correctly

The one means I’ve discovered to repair that is to manually open a brand new precise full app window by way of File > New, wherein case the app works superb once more within the new window.

The next very simple code in a default Xcode mission illustrates the difficulty:

import SwiftUI

@principal
struct staleApp: App {
  @State personal var isBright = true
  var physique: some Scene {
    WindowGroup() {
      ZStack {
        (isBright ? Coloration.white : Coloration.black).ignoresSafeArea()
        Button("TOGGLE") { isBright.toggle(); print("TAPPED") }
      }
    }
  }
}

For the code above, after Hiding the app and placing the pc to sleep for 60 seconds or extra, the button now not swaps views, though the print statements nonetheless seem within the console upon tapping the button. Additionally, whereas on this buggy state, i can get the view to replace to the present state (i.e. the view triggered by the final faucet) by manually dragging the nook of the app window to resize the window. However after resizing, the view once more doesn’t replace upon button tapping till I resize the window once more.

so it seems the diff engine is mucked or that the Scene or WindowGroup are now not accurately working on the primary thread

I’ve tried rebuilding all the view hierarchy by updating .id() on views however this strategy does NOT work. I’ve tried many different choices/hacks however haven’t been capable of reset the ‘view engine’ aside from opening a brand new window manually or through the use of: @Surroundings(.openWindow) personal var openWindow

openWindow may very well be a viable resolution besides there is no technique to programmatically shut the outdated window for isiOSAppOnMac (@Surroundings(.dismissWindow) personal var dismissWindow does not work for iOS)