Setting environment variables in Flutter

问题:

For example, building a client for an API, like Twitch.

In a Dart CLI binary, I could use a generic environment variable, or a Dart definition variable. For example, using both as fallbacks:

main() {
  String clientId = 
      // dart -dCLIENT_ID='abc bin/example.dart
      // This is considered "compiled-into" the application.
      const String.fromEnvironment('CLIENT_ID') ??

      // CLIENT_ID='abc' dart bin/example.dart
      // This is considered a runtime flag.
      Platform.environment['CLIENT_ID'];

  // Use clientId.
}

Does Flutter have a way of setting either/both of these, specifically...

• During dev time
• When shipped to prod

Happy to help with some docs once I figure out how :)

回答1:

For configuration a common pattern I've seen is to use separate main files instead. i.e.

flutter run -t lib/production_main.dart

and

flutter build apk -t lib/debug_main.dart

And then in those different main files set up the configurations desired.

In terms of reading ids, you can do that from arbitrary assets https://flutter.io/assets-and-images/.

I believe it is possible in Flutter to read from the environment as you suggest, however I don't know how to set those environment variables on iOS or Android.