React Routing still showing root component even after using exact - reactjs

Question

I am still a newbie to React. So here I am rendering the root component with two routes: Home and About located in functional components: home.js and about.js respectively. However, even after using exact attribute and , the root component keeps on rendering above. I still cannot figure out how to not render the root component when I am redirecting to any of the mentioned routes?
Heres the live demo: https://codesandbox.io/s/vmz6zwq0k7

Answer 1

The Route component is acting like a "placeholder" for the component you want to render when the URL matches. everything above it (parents and siblings) wont get affected.
Given this code example:
render() {
return (
<BrowserRouter>
<div className="App">
<Link to="/home"> Home </Link>{" "}
|
<Link to="/about"> About Us </Link>{" "}
<div>
<Route exact path="/home" component={Home} />
<Route exact path="/about" component={About} />
</div>
</div>
</BrowserRouter>
);
}
This line of code:
<Route exact path="/home" component={Home} />
Is only a "placeholder" for the Home component. It won't render anything only when the path is matching "/home".
When the path will match, the Route component will render the passed component, The Home component in this case.
It will not affect the entire app tree, and for a good reason!
If the entire app would get re-rendered and replaced with the Home component you would loose the navigation links.

Answer 2

I had the same problem looking at the react-routing getting started portion here. https://reactrouter.com/web/guides/quick-start
I placed my Router/BrowserRouter in my App component. Instead place the router in your index.js file like so
import React from 'react';
import ReactDOM from 'react-dom';
import './index.css';
import App from './App';
import reportWebVitals from './reportWebVitals';
import { BrowserRouter } from "react-router-dom";
ReactDOM.render(
<React.StrictMode>
<BrowserRouter>
<App />
</BrowserRouter>
</React.StrictMode>,
document.getElementById('root')
);
Then your app component can look like so and the root route wont be matched if about or users is matched.
import React from "react";
import {
Switch,
Route,
Link
} from "react-router-dom";
export default function App() {
return (
<div>
<nav>
<ul>
<li>
<Link to="/">Home</Link>
</li>
<li>
<Link to="/about">About</Link>
</li>
<li>
<Link to="/users">Users</Link>
</li>
</ul>
</nav>
{/* A <Switch> looks through its children <Route>s and
renders the first one that matches the current URL. */}
<Switch>
<Route path="/about">
<About />
</Route>
<Route path="/users">
<Users />
</Route>
<Route path="/">
<Home />
</Route>
</Switch>
</div>
);
}
function Home() {
return <h2>Home</h2>;
}
function About() {
return <h2>About</h2>;
}
function Users() {
return <h2>Users</h2>;
}