Fixing Nested Route Rendering Issues in React Router v6

Nested routes are a powerful feature in React Router v6, but they often cause confusion when not implemented correctly. Here’s how to properly structure and render nested routes.

The Core Problem

Common symptoms of incorrect nested route implementation:

• Child routes not appearing
• Layout components rendering incorrectly
• Blank screens where content should be
• URL changes but content doesn’t update

Correct Implementation

1. Basic Nested Route Structure

<Routes>
  <Route path="/" element={<Layout />}>
    <Route index element={<Home />} />
    <Route path="about" element={<About />} />
    <Route path="products" element={<Products />}>
      <Route index element={<ProductList />} />
      <Route path=":id" element={<ProductDetail />} />
    </Route>
  </Route>
</Routes>

2. Layout Component with Outlet

import { Outlet } from 'react-router-dom';

function Layout() {
  return (
    <div>
      <header>My App</header>
      <main>
        <Outlet /> {/* Nested routes render here */}
      </main>
      <footer>© 2023</footer>
    </div>
  );
}

Common Mistakes and Solutions

❌ Missing Outlet in Parent Component

function Products() {
  return <ProductFilters />; {/* ❌ No Outlet for child routes */}
}

✅ Fix: Add Outlet where children should render

function Products() {
  return (
    <div>
      <ProductFilters />
      <Outlet /> {/* ✅ Child routes appear here */}
    </div>
  );
}

❌ Incorrect Path Structure

<Route path="/products" element={<Products />}>
  <Route path="/details" element={<Details />} /> {/* ❌ Absolute path */}
</Route>

✅ Fix: Use relative paths

<Route path="products" element={<Products />}>
  <Route path="details" element={<Details />} /> {/* ✅ Relative to parent */}
</Route>

❌ Wrong Route Ordering

<Routes>
  <Route path=":userId" element={<UserProfile />} />
  <Route path="settings" element={<Settings />} /> {/* ❌ Will never match */}
</Routes>

✅ Fix: More specific routes first

<Routes>
  <Route path="settings" element={<Settings />} />
  <Route path=":userId" element={<UserProfile />} />
</Routes>

Advanced Patterns

1. Multiple Nested Layers

<Routes>
  <Route path="/" element={<MainLayout />}>
    <Route path="dashboard" element={<DashboardLayout />}>
      <Route index element={<DashboardHome />} />
      <Route path="analytics" element={<Analytics />} />
    </Route>
  </Route>
</Routes>

2. Pathless Layout Routes

<Routes>
  <Route element={<AuthLayout />}> {/* No path */}
    <Route path="login" element={<Login />} />
    <Route path="register" element={<Register />} />
  </Route>
</Routes>

// AuthLayout.js
function AuthLayout() {
  return (
    <div className="auth-page">
      <Outlet />
    </div>
  );
}

3. Dynamic Breadcrumbs

function ProductPage() {
  const matches = useMatches();
  const crumbs = matches.map((match) => ({
    path: match.pathname,
    title: match.handle?.crumb,
  }));

  return (
    <div>
      <Breadcrumbs crumbs={crumbs} />
      <Outlet />
    </div>
  );
}

Debugging Techniques

1. Check the URL structure matches your route paths
2. Verify Outlet placement in parent components
3. Use useMatches() to see current route matches:

   const matches = useMatches();
   console.log(matches);

4. Inspect route ranking with React DevTools
5. Add route tracing:

   function RouteDebugger() {
     const location = useLocation();
     const matches = useMatches();

     useEffect(() => {
       console.log('Current location:', location);
       console.log('Route matches:', matches);
     }, [location]);

     return null;
   }

   // Add to your app
   <Routes>
     <Route path="*" element={<RouteDebugger />} />
   </Routes>

Complete Example

// App.js
function App() {
  return (
    <Routes>
      <Route path="/" element={<MainLayout />}>
        <Route index element={<HomePage />} />
        <Route path="shop" element={<ShopLayout />}>
          <Route index element={<ProductList />} />
          <Route path=":category" element={<CategoryPage />}>
            <Route index element={<CategoryProducts />} />
            <Route path=":productId" element={<ProductDetail />} />
          </Route>
          <Route path="cart" element={<CartPage />} />
        </Route>
        <Route path="*" element={<NotFound />} />
      </Route>
    </Routes>
  );
}

// MainLayout.js
function MainLayout() {
  return (
    <div className="app">
      <Header />
      <main>
        <Outlet />
      </main>
      <Footer />
    </div>
  );
}

// ShopLayout.js
function ShopLayout() {
  return (
    <div className="shop">
      <ShopSidebar />
      <div className="shop-content">
        <Outlet />
      </div>
    </div>
  );
}

Key Takeaways

1. Always include an Outlet in parent route components
2. Use relative paths for nested routes
3. Order routes from most specific to least specific
4. Structure layouts hierarchically to match your UI
5. Leverage pathless routes for shared layouts

Properly structured nested routes create maintainable, flexible navigation systems that mirror your application’s UI hierarchy. Following these patterns ensures your routes render exactly where and when you expect them to.