Parallel routes concept in NextJS - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define a parallel route segment in Next.js.

NextJS

export const metadata = { title: 'Dashboard' };

export default function DashboardLayout({ children }) {
  return <section>[1]{children}</section>;
}

Drag options to blanks, or click blank then click option'

A<main>

B<div>

C<header>

D<footer>

Attempts:

3 left

💡 Hint

Common Mistakes

Using non-semantic tags like

instead of

.

Wrapping children in header or footer tags which are not appropriate here.

The <main> tag is used to wrap the main content in a layout, which is common in Next.js layouts including parallel routes.

2fill in blank

medium

Complete the code to import a parallel route segment in Next.js App Router.

NextJS

import [1] from './(admin)/settings/page';

Drag options to blanks, or click blank then click option'

ASettingsPage

BSettingsComponent

CSettingsRoute

DSettings

Attempts:

3 left

💡 Hint

Common Mistakes

Using component names that don't match the folder name.

Adding extra suffixes like 'Page' or 'Component' unnecessarily.

When importing a parallel route segment, the folder name is used as the import name, here 'Settings' matches the folder '(admin)/settings'.

3fill in blank

hard

Fix the error in the parallel route segment definition by completing the blank.

NextJS

export default function [1]() {
  return <div>Admin Settings</div>;
}

Drag options to blanks, or click blank then click option'

ASettings

BSettingsPage

CAdminSettings

DSettingsLayout

Attempts:

3 left

💡 Hint

Common Mistakes

Using unrelated function names that confuse the route segment.

Adding 'Page' or 'Layout' suffixes incorrectly.

The function name should match the segment name for clarity and convention, here 'Settings' matches the route segment folder.

4fill in blank

hard

Fill both blanks to correctly define parallel routes in Next.js App Router.

NextJS

export const parallelRoutes = {
  [1]: () => import('./(marketing)/home/page'),
  [2]: () => import('./(admin)/dashboard/page')
};

Drag options to blanks, or click blank then click option'

Amarketing

Badmin

Cdashboard

Dhome

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping keys and import folder names.

Using page names instead of folder names as keys.

The keys in the parallelRoutes object represent the route names, matching the folder names 'marketing' and 'admin'.

5fill in blank

hard

Fill all three blanks to create a parallel route layout with metadata and children rendering.

NextJS

export const metadata = { title: '[1]' };

export default function [2]Layout({ children }) {
  return <[3]>{children}</[3]>;
}

Drag options to blanks, or click blank then click option'

AAdmin Panel

BAdmin

Cmain

Dsection

Attempts:

3 left

💡 Hint

Common Mistakes

Using non-semantic tags like

instead of

.

Mismatching function names and metadata titles.

Leaving blanks empty or using incorrect strings.

The metadata title is 'Admin Panel', the function name matches the segment 'Admin', and the children are wrapped in a semantic <section> tag.

Practice

1. What is the main purpose of parallel routes in Next.js?

easy

A. To disable navigation between pages

B. To load pages sequentially one after another

C. To replace client-side routing with server-side only

D. To display multiple parts of a page simultaneously

Solution

1. Step 1: Understand what parallel routes do

   Parallel routes allow showing multiple UI sections at the same time on a page.

2. Step 2: Compare options with this understanding

   Only To display multiple parts of a page simultaneously correctly describes this purpose; others describe unrelated behaviors.

3. Final Answer:

   To display multiple parts of a page simultaneously -> Option D

4. Quick Check:

   Parallel routes = show multiple parts [OK]

Hint: Parallel routes show multiple page parts at once [OK]

Common Mistakes:

• Thinking parallel routes load pages one after another
• Confusing parallel routes with disabling navigation
• Assuming parallel routes replace client-side routing

2. Which folder naming pattern is used to define a parallel route in Next.js?

easy

A. Using parentheses like (route)

B. Using square brackets like [route]

C. Using curly braces like {route}

D. Using angle brackets like <route>

Solution

1. Step 1: Recall folder naming for parallel routes

   Next.js uses parentheses around folder names to mark parallel routes.

2. Step 2: Match options to this rule

   Only Using parentheses like (route) uses parentheses, which is correct for parallel routes.

3. Final Answer:

   Using parentheses like (route) -> Option A

4. Quick Check:

   Parallel routes folder = parentheses [OK]

Hint: Parallel routes folders use parentheses ( ) [OK]

Common Mistakes:

• Using square brackets which are for dynamic routes
• Confusing with curly braces or angle brackets
• Not using any special characters for parallel routes

3. Given this folder structure in Next.js:

app/
  (sidebar)/
    page.jsx
  (content)/
    page.jsx
  layout.jsx

What will happen when the app renders layout.jsx with parallel routes?

medium

A. Both sidebar and content pages render side by side inside layout

B. Only the sidebar page renders, content is ignored

C. Only the content page renders, sidebar is ignored

D. Neither sidebar nor content pages render automatically

Solution

1. Step 1: Understand parallel routes folder names

   Folders named with parentheses define parallel routes that render simultaneously.

2. Step 2: Apply to given structure

   Both (sidebar) and (content) are parallel routes, so their pages render side by side inside layout.

3. Final Answer:

   Both sidebar and content pages render side by side inside layout -> Option A

4. Quick Check:

   Parallel routes render all named folders simultaneously [OK]

Hint: Parentheses folders render together inside layout [OK]

Common Mistakes:

• Thinking only one parallel route renders at a time
• Assuming parallel routes need manual import to render
• Confusing parallel routes with nested routes

4. You have this code in your layout.jsx to render parallel routes:

import { Slot } from 'next/navigation';

export default function Layout() {
  return (
    

      <Slot name="sidebar" />
      <Slot name="content" />
    
  );
}

Why does this code cause an error?

medium

A. Because Slot must be imported from 'next/navigation' as a named import

B. Because <Slot /> should be self-closing JSX tags, not string literals

C. Because parallel routes cannot use Slot components

D. Because Slot requires a default export, not named

Solution

1. Step 1: Check JSX syntax in return statement

   The code uses <Slot name="sidebar" /> as a string literal, not as JSX tags.

2. Step 2: Correct JSX usage

   It should be <Slot name="sidebar" /> without quotes, as a self-closing JSX component.

3. Final Answer:

   Because <Slot /> should be self-closing JSX tags, not string literals -> Option B

4. Quick Check:

   JSX tags must not be strings [OK]

Hint: Use JSX tags, not strings, for [OK]

Common Mistakes:

• Writing JSX tags as strings inside return
• Importing Slot incorrectly
• Thinking Slot can't be used in parallel routes

5. You want to create a page with a sidebar and main content using parallel routes. Which folder structure and code snippet correctly implements this in Next.js?

app/
  (sidebar)/
    page.jsx
  (main)/
    page.jsx
  layout.jsx

And in layout.jsx:

export default function Layout() {
  return (
    

      {/* What goes here? */}
    
  );
}

hard

A. <Slot />

B. <Slot name="content" />
<Slot name="sidebar" />

C. <Slot name="sidebar" />
<Slot name="main" />

D. <Outlet name="sidebar" />
<Outlet name="main" />

Solution

1. Step 1: Match folder names to Slot names

   Folders are named (sidebar) and (main), so Slots must use these exact names.

2. Step 2: Check code snippet for correct Slot usage

   <Slot name="sidebar" /> <Slot name="main" /> uses <Slot name="sidebar" /> and <Slot name="main" />, matching folder names and correct JSX syntax.

3. Final Answer:

   <Slot name="sidebar" /> <Slot name="main" /> -> Option C

4. Quick Check:

   Slot names = folder names [OK]

Hint: Slot names must match parallel route folder names [OK]

Common Mistakes:

• Using wrong Slot names that don't match folders
• Using instead of
• Using only one Slot for multiple parallel routes