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2026-09-09-app-error-screen-builder

title: The startup error screen is built from the error affects: dartway_flutter: "0.9.0"​

Who is affected​

A project that passes its own errorScreen to DwAppLoadingOptions — in the DwAppRunner of its app file. A project that uses the default screen has nothing to change.

What to change​

DwAppLoadingOptions.errorScreen (a widget) is now errorScreenBuilder (a function of the error that failed the start):

- DwAppLoadingOptions.withNativeSplash(errorScreen: const MyStartupError())
+ DwAppLoadingOptions.withNativeSplash(
+   errorScreenBuilder: (error, stackTrace) => MyStartupError(error: error),
+ )

Ignoring both arguments is a valid answer — (_, _) => const MyStartupError() — but the error is worth putting on the screen. The person looking at a failed start is usually the one who will be asked what happened, and "please contact administrator" with nothing else is not something they can report.

How to check​

dart analyze in the Flutter package: errorScreen no longer exists, so a missed call site is a compile error rather than something that surfaces on a launch nobody watched.