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Flutter 多继承的ChangeNotifierProvider_Flutter_Dart_Flutter Provider_Flutter Change Notifier - Fatal编程技术网

Flutter 多继承的ChangeNotifierProvider

Flutter 多继承的ChangeNotifierProvider,flutter,dart,flutter-provider,flutter-change-notifier,Flutter,Dart,Flutter Provider,Flutter Change Notifier,我有以下服务结构,而不是单一的大型a类: class A extends ChangeNotifier { ... } class B extends A { ... } class C extends A { ... } class D extends A { ... } 我可以做到以下几点: MultiProvider( providers: [ ChangeNotifierProvider(create: (_) => A()),

我有以下服务结构,而不是单一的大型a类:

class A extends ChangeNotifier {
...
}

class B extends A {
...
}

class C extends A {
...
}
class D extends A {
...
}
我可以做到以下几点:

 MultiProvider(
      providers: [
        ChangeNotifierProvider(create: (_) => A()),
        ChangeNotifierProvider(create: (_) => B()),
        ChangeNotifierProvider(create: (_) => C()),
        ChangeNotifierProvider(create: (_) => D()),
      ],

但是有没有其他方法可以在一个步骤中提供所有子类,而不是在一个
多提供程序中单独提供每个子类

我认为您必须创建一个新类来保存所有实例,然后只提供它。如果你是这样问的话,没有内置的dart进程来“初始化某个对象的所有子类”。我已经试过了,但没有成功。