flutter_field_not_map

The value of the 'flutter' field is expected to be a map.

The analyzer produces this diagnostic when the value of the flutter key isn't a map.

The following code produces this diagnostic because the value of the top-level flutter key is a string:

name: example
flutter: true

If you need to specify Flutter-specific options, then change the value to be a map:

name: example
flutter:
  uses-material-design: true

If you don't need to specify Flutter-specific options, then remove the flutter key:

name: example