Flutter Provider 重新初始化模型 [英] Flutter Provider reinitialize model

问题描述

我使用 MultiProvider，然后创建我的所有模型.延迟加载已启用，因此当我打开我的页面小部件时，当我调用 Provider.of<>(context) 时会调用我的模型的构造函数.

I use MultiProvider and then create all my models. Lazy loading is enabled and as such when I open my page widget the constructor of my model is called when I call Provider.of<>(context).

这会初始化我的模型，模型会获得新数据.

This initialize my model and the model gets fresh data.

然而，我有以下问题，当我弹出视图(小部件)并稍后重新访问视图(小部件)时，再次调用 Provider.of<>(context)，但由于模型已经初始化我从模型中获取以前的数据(这很有用，因为我确实使用它来保留某些屏幕之间的状态).

I have the following issue however, when I pop the view(widget) and revisit the view(widget) later, Provider.of<>(context) is called again, but since the model was already initialized I get the previous data from the model (This is useful because I do use this to preserve state between certain screens).

我需要重新初始化我的模型，因为我需要刷新我的数据并重置页面值，并且由于永远不会再次调用构造函数，我没有得到任何这些.

I need my model to reinitialize since I need to refresh my data and reset the page values, and since the constructor is never called again, I don't get any of these.

无论我做什么，如果我从 initState()/didChangeDependencies() 调用 initialize 方法，它总是会出错，因为我在小部件时更改数据正在建设中.

No matter what I do, if I call the initialize method from initState() / didChangeDependencies() it always error since I'm changing the data while the widget is building.

我正在寻找类似以下内容:

I'm looking for something like the following:

MyChangeNotifier variable = MyChangeNotifier();

ChangeNotifierProvider.value(
  value: variable,
  child: child()
)

重新初始化我的班级，但从我读到的内容来看，这很糟糕，不知道在哪里调用它.

To reinitialize my class, but from what I read this is bad and don't know where to call it.

我不知道如何继续，任何帮助将不胜感激.

I have no idea how to proceed and any help would be appreciated.

推荐答案

所以我在 Provider 的实际文档中找到了我想要的东西 此处.

So I found what I was looking for in the Provider actual documentation here.

关键是调用将更新 UI 或触发 Future.microTask() 内部重建的代码.这只会在未来完成后触发重建，而不会在小部件树仍在构建时触发重建.

The key is to call your code that would update the UI or trigger a rebuild inside a Future.microTask(). This will only then trigger the rebuild once the future completes and not trigger the rebuild while the widget tree is still building.

@override
initState() {
  super.initState();
  Future.microtask(() =>
    context.read<MyNotifier>(context).getMyData(); // Or in my situation initialize the page.
  );
}

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