Error: Method not found: 'NullThrownError' in flutter

Question

I was getting the below error while running the flutter application post flutter upgrade to 3.10.6

Failed to build build_runner:build_runner:
/C:/Users/Admin/AppData/Local/Pub/Cache/hosted/pub.dev/build_runner-2.3.2/lib/src/build_script_generate/bootstrap.dart:76:40: Error: Method not found: 'NullThrownE
rror'.
      final error = e[0] as Object? ?? NullThrownError();
                                       ^^^^^^^^^^^^^^^

Answer 1

For me this happen because the incompatibility of each package used. I think the packages that relate to build runner are floor_generator and retrofit_generator. You can simply resolve the issue by following these:

• remove retrofit_generator, floor_generator and build_runner from dev_dependencies
• add packages from terminal -> flutter pub add dev:build_runner, flutter pub add dev:floor_generator and flutter pub add dev:retrofit_generator
• try to build the build_runner again -> dart run build_runner build

or if the error still occur try this package version:

• dependencies: floor: ^1.4.2 retrofit: ^3.0.1
• dev_dependencies: build_runner: ^2.4.6 retrofit_generator: ^4.2.0 floor_generator: ^1.4.2