在 Flutter 中捕获未处理的异常

Question

I'm trying to catch all unhandled exceptions in my Flutter app. Here's my main.dart:

void main() async {
  FlutterError.onError = (FlutterErrorDetails details) {
    print("FlutterError.onError");
  };

  try {
    runZoned<Future<void>>(
      () async {
        runApp(App());
      },
      onError: (dynamic error, StackTrace stackTrace) {
        print("runZoned.onError");
      },
    );
  } catch (ex) {
    print("main.catch");
  }
}

... however, none of these methods works, and my app outputs the following when running in the iOS simulator:

[VERBOSE-2:ui_dart_state.cc(166)] Unhandled Exception: SocketException: OS Error: Connection refused, errno = 61, address = localhost, port = 57562

... how do I catch this exception?

Answer 1

OK I've solved this. Some of my initialisation logic was outside the runZoned block. I incorrectly assumed that all that was needed inside runZoned was the call to runApp . I've put everything inside the runZoned and it's now correctly catching the errors.