Category "flutter-exception"

I'm creating and validating a dynamic form in Flutter, but when I change the page and return to the previous page I get an error. how can i solve

It works in release mode but I get an error in debug mode class UrunHizmetWidget extends StatefulWidget { int index; final state = _UrunHizmetWidgetState();

Flutter facebook app events : lateinit property anonymousId has not been initialized

I'm trying to call Facebook app events in my flutter project. I'm using the dependency facebook_app_events: ^0.12.0. meta-data is also added in the manifest fil