Plugin Registration crash when adopting UISceneDelegate due to nil FlutterEngine

[realdev-fr]

Hi,

I migrated my IOS app due to new recommandations of Flutter/iOS : https://docs.flutter.dev/release/breaking-changes/uiscenedelegate

After migrating and launching my app, I got this error :

flutter_contacts/SwiftFlutterContactsPlugin.swift:435: Fatal error: Unexpectedly found nil while unwrapping an Optional value
Process 2128 stopped
* thread #1, queue = 'com.apple.main-thread', stop reason = Fatal error: Unexpectedly found nil while unwrapping an Optional value
    frame #3: 0x0000000103b9996c flutter_contacts`static SwiftFlutterContactsPlugin.register(registrar=0x0000000105558d40) at SwiftFlutterContactsPlugin.swift:435:72
   432 	            name: "github.com/QuisApp/flutter_contacts/events",
   433 	            binaryMessenger: registrar.messenger()
   434 	        )
-> 435 	        let rootViewController = UIApplication.shared.delegate!.window!!.rootViewController!
    	                                                                       ^
   436 	        let instance = SwiftFlutterContactsPlugin(rootViewController)
   437 	        registrar.addMethodCallDelegate(instance, channel: channel)
   438 	        eventChannel.setStreamHandler(instance)
Target 0: (Runner) stopped.

flutter --version :

Flutter 3.41.0-0.1.pre • channel beta • https://github.com/flutter/flutter.git
Framework • revision be9275b822 (4 days ago) • 2026-01-26 10:44:57 -0500
Engine • hash f724992bc20c92305c51047e400816b13ab6c4c0 (revision d8756bc5ef) (7 days ago) • 2026-01-22 16:11:54.000Z
Tools • Dart 3.11.0 (build 3.11.0-296.4.beta) • DevTools 2.54.1

[El3aQeeD]

I have same issue

[chilkurisainath]

Facing the same issue, any solution so far on this?

[DanielBrunner97]

@chilkurisainath @El3aQeeD @realdev-fr Are you getting the error when using the newest beta version(2.0.0-beta.2)?