我一直在尝试使用我的redux知识来构建小项目，以便在这个主题上更多地训练自己。最近，我一直在尝试使用redux，但我没有得到任何错误，也没有开发工具的错误，我的页面是空白的。我将张贴我的代码下面，所以它更清楚。所以我开始我的代码与基本的redux样板，我记住了。我创建了一个userslice和一个store，然后将store作为的 Package 器提供，但在花了几个小时后，我无法修复代码，代码应该给予我初始化的useselector挂钩在div中返回用户名，但它似乎不起作用
App.js:

import React from 'react';
import { useSelector } from 'react-redux';

import './App.css';

function App() {
  const username = useSelector(state => state.username)
  return (
    <div className="App">
    
   {username}

     
     
    </div>
  );
}

export default App;

userSlice.js

import { createSlice } from "@reduxjs/toolkit";

export const userSlice = createSlice({
    name:'user'
,
initialState:{
    username:'Tony stark',
    post:'',

},

reducers:{
    updatePost:(state,action)=>{
        state.username = action.payload;

    }
}})

export const { updatePost} = userSlice.actions;
export default userSlice.reducers;

store.js

import { configureStore } from '@reduxjs/toolkit';

import userSlice from '../redux/userSlice'
export const store = configureStore({
  reducer: {
    
    user: userSlice,
  },
});

index.js

import React from 'react';
import { createRoot } from 'react-dom/client';
import { Provider } from 'react-redux';
import { store } from '../src/redux/store'
import App from './App';

import './index.css';

const container = document.getElementById('root');
const root = createRoot(container);

root.render(
  <React.StrictMode>
    <Provider store={store}>
      <App />
    </Provider>
  </React.StrictMode>
);

// If you want to start measuring performance in your app, pass a function
// to log results (for example: reportWebVitals(console.log))