Unhandled exception: type 'Null' is not a subtype of type 'Map<dynamic, dynamic>' in type cast

[Ngochiendev]

Describe the bug
When I use this command dart run flutter_native_splash:create --path=native_splash_generator.yaml , an error appears like the image below
Error -> Building package executable...
Built flutter_native_splash:create.
Unhandled exception:
type 'Null' is not a subtype of type 'Map<dynamic, dynamic>' in type cast
#0 getConfig (package:flutter_native_splash/cli_commands.dart:350:67)
#1 createSplash (package:flutter_native_splash/cli_commands.dart:42:18)
#2 main (file:///Users/macos/.pub-cache/hosted/pub.dev/flutter_native_splash-2.3.8/bin/create.dart:31:5)
#3 _delayEntrypointInvocation. (dart:isolate-patch/isolate_patch.dart:295:33)
#4 _RawReceivePort._handleMessage (dart:isolate-patch/isolate_patch.dart:184:12)

Screenshots

Please give me solution to fix this error

[jonbhanson]

Please add your config.

[jonbhanson]

Closed due to inactivity. Feel free to reopen if you're still having trouble.

[BujusKrachus]

I was experiencing the same issue. Though it's not an actual package issue, rather a documentation/usage one. I am adding this comment in case anybody else is confused.

Steps to reproduce:

1. Create a new Flutter project. I used Android Studio and Flutter SDK 3.16.7 for it.
2. run flutter pub add flutter_native_splash
3. add flutter_native_splash: color: "#000000" to pubspec.yaml
4. run dart run flutter_native_splash:create, this will work
5. run dart run flutter_native_splash:create --path=splash.yaml, this will not work because splash.yaml does not yet exist
6. Thus create a new file splash.yaml
7. run dart run flutter_native_splash:create --path=splash.yaml again, this will not work because of the Unhandled exception: type 'Null' is not a subtype of type 'Map<dynamic, dynamic>' in type cast

Full output of command:

dart run flutter_native_splash:create --path=splash.yaml
Building package executable... 
Built flutter_native_splash:create.
Unhandled exception:
type 'Null' is not a subtype of type 'Map<dynamic, dynamic>' in type cast
#0      getConfig (package:flutter_native_splash/cli_commands.dart:350:67)
#1      createSplash (package:flutter_native_splash/cli_commands.dart:42:18)
#2      main (file:///C:/Users/user/AppData/Local/Pub/Cache/hosted/pub.dev/flutter_native_splash-2.3.10/bin/create.dart:31:5)
#3      _delayEntrypointInvocation.<anonymous closure> (dart:isolate-patch/isolate_patch.dart:295:33)
#4      _RawReceivePort._handleMessage (dart:isolate-patch/isolate_patch.dart:184:12)

What's going on?
you either specify the parameters (splash config instructions) in pubspec.yaml and run dart run flutter_native_splash:create OR specify the parameters in a seperate file (e.g. splash.yaml) and run dart run flutter_native_splash:create --path=splash.yaml.
In my opinion the Readme is a bit misleading here and the exception output could be handled better. If someone has some time this could get improved.

Also maybe helpful to note: The splash screen will get displayed despite the error, as the issue is just a usage one (only use one command/method).

Future improvements

• clarify usage in readme (2. Run the package)
• handle exception better in case of no splash.yaml
• handle exception better in case of no flutter_native_splash section in pubspec.yaml

Hope this helps any future readers :)