flutter provider changenotifierprovider 问题

Question

我正在查看 flutter 网站上的以下代码:

void main() {
  runApp(
    MultiProvider(
      providers: [
        ChangeNotifierProvider(create: (context) => CartModel()),
        Provider(create: (context) => SomeOtherClass()),
      ],
      child: MyApp(),
    ),
  );
}

我想知道，Provider 和 ChangeNotifierProvider 有什么区别？

谢谢!

Answer 1

来自 provider package documentation (一直往下):

Provider: The most basic form of provider. It takes a value and exposes it, whatever the value is.

ListenableProvider: A specific provider for Listenable object. ListenableProvider will listen to the object and ask widgets which depend on it to rebuild whenever the listener is called.

ChangeNotifierProvider: A specification of ListenableProvider for ChangeNotifier. It will automatically call ChangeNotifier.dispose when needed.

所以， ChangeNotifierProvider是 Provider 的特定类型它将监听该对象并在此对象更新后重建其依赖的小部件。此外，它会自动调用 dispose需要时的方法。
Provider是通用提供程序，没有任何更复杂的功能，非常像优化的 Inherited Widget .