Migration from UIKit app lifecycle to SwiftUI app lifecycle fails

Originator:florentmorin
Number:rdar://FB9692750 Date Originated:
Status:Open Resolved:
Product:SwiftUI Framework Product Version:
Classification: Reproducible:
 
I currently have an app on the App Store, built with UIKit.

App was rewritten to SwiftUI during this summer.
Everything is OK with fresh install.

But, when app is launched after an update, I can only saw a black screen.

The only way to solve this is set a blank UISceneDelegateClassName in Info.plist file.
But this solution create a warning when launching the app.

1. Create a UIKit app
2. Launch the app on simulator
3. Replace UIKit lifecycle by SwiftUI lifecycle (and remove unnecessary entries of Info.plist)
4. Launch the app

Expected result: the app
Current result: a black screen

For easier debugging (especially to migrate between apps), a complete source code with 3 branches is attached:
- main: UIKit sample app
- swiftui: SwiftUI sample app
- swiftui-fix-scenedelegate: SwiftUI app with a fix for Scene Delegate (with warning at launch)

https://github.com/florentmorin/SwiftUIUpdate

Comments

Try to add multiple scenes support in your info.plist

<key>UIApplicationSceneManifest</key> <dict> <key>UIApplicationSupportsMultipleScenes</key> <true/> </dict>

By Jos.shad at Oct. 22, 2021, 3 p.m. (reply...)

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