React 怎样重新渲染整个App

Question

有如下代码，请问在shell reload之后怎么重新 render 整个App， 这也写App内部的state都没有清掉，感觉App像是单例，望解答原理。

import * as React from 'react';
import * as ReactDOM from 'react-dom';
import App from './App';
import Bridge from '../util/bridge';

export function initDevTools(shell: any) {
  // initApp(shell);
  //   initStorage().then(() => {
  initApp(shell);
  shell.onReload(() => {
    // if (app) {
    //   app.$el.classList.add('disconnected');
    //   app.$destroy();
    // }
    Bridge.instance.removeAllListeners();
    initApp(shell);
  });
  //   });
}
function initApp(shell: any) {
  shell.connect((bridge: Bridge) => {
    Bridge.instance = bridge;
    ReactDOM.render(<App />, document.querySelector('#app'));
  });
}