flutter - 常量创建的参数必须是Flutter上的常量表达式

Question

我使用了Flavor并定义了两个主要的类。而且我还使用了Chopper。如何设置基于baseUrl的环境？

import 'package:meta/meta.dart';

enum BuildFlavor { production, development }

BuildEnvironment get env => _env;
BuildEnvironment _env;

class BuildEnvironment {
  final String ssoBaseUrl;
  final BuildFlavor flavor;

  BuildEnvironment._init(
      {this.ssoBaseUrl,
      this.flavor});

  static void init(
          {@required flavor,
          @required ssoBaseUrl}) =>
      _env ??= BuildEnvironment._init(
          flavor: flavor,
          ssoBaseUrl: ssoBaseUrl);
}

main.dev.dart

void main() {
  BuildEnvironment.init(
      flavor: BuildFlavor.development,
      ssoBaseUrl: 'http://15.88.219.20');
  assert(env != null);
  runApp(MultiProvider(
    providers: globalProviders,
    child: MyApp(),
  ));
}

斩波器

@ChopperApi(baseUrl:'${env.ssoBaseUrl}')
abstract class Services extends ChopperService {
  static Services create([ChopperClient client]) => _$Services(client);

  @Post(path: '/sso-dev/registration')
  Future<Response> registerPost(

错误消息

Answer 1

注释仅需提供const值。由于env是getter属性，因此它不是const。恐怕您将无法通过这种方式指定baseUrl。