Responsive images in NextJS - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to import the Next.js Image component.

NextJS

import [1] from 'next/image';

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

Aimg

BImage

CPicture

DNextImage

Attempts:

3 left

💡 Hint

Common Mistakes

Using lowercase 'img' which is the HTML tag, not the Next.js component.

Using 'Picture' which is not a Next.js import.

Using 'NextImage' which is not the correct import name.

The Next.js Image component is imported as Image from 'next/image'.

2fill in blank

medium

Complete the code to set the image source to '/logo.png'.

NextJS

<Image src=[1] alt="Logo" width={100} height={100} />

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

A'logo.png'

B"logo.png"

C'/logo.png'

D"logo"

Attempts:

3 left

💡 Hint

Common Mistakes

Omitting the leading slash which causes the image not to load.

Using just the filename without extension.

Using incorrect quotes or missing quotes.

The src attribute requires the path starting with a slash for public folder images, so '/logo.png' is correct.

3fill in blank

hard

Fix the error in the code to make the image responsive using the 'fill' layout.

NextJS

<Image src="/banner.jpg" alt="Banner" [1] />

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

Aresponsive

Bfill={true}

Clayout="responsive"

Dlayout="fill"

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'responsive' without quotes which causes syntax errors.

Using 'fill={true}' which is not a valid prop.

Using 'layout="responsive"' which is different from 'fill'.

Next.js Image uses layout="fill" to make the image fill its parent container responsively.

4fill in blank

hard

Fill both blanks to add width and height props for a fixed size image.

NextJS

<Image src="/avatar.png" alt="User Avatar" width=[1] height=[2] />

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

A150

B100

C200

D250

Attempts:

3 left

💡 Hint

Common Mistakes

Using strings instead of numbers for width and height.

Swapping width and height values incorrectly.

Omitting either width or height.

The width and height props must be numbers. Here width is 100 and height is 150 for a fixed size image.

5fill in blank

hard

Fill all three blanks to create a responsive image with priority loading and alt text 'Hero Image'.

NextJS

<Image src=[1] alt=[2] priority=[3] width={800} height={600} />

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

A"/hero.jpg"

B"Hero Image"

Ctrue

Dfalse

Attempts:

3 left

💡 Hint

Common Mistakes

Using alt text without quotes.

Setting priority to false which disables priority loading.

Omitting quotes around the src path.

Use the image path "/hero.jpg", alt text "Hero Image", and set priority to true for faster loading.

Practice

1. What is the main benefit of using responsive images in a Next.js app?

easy

A. They load the right image size for different screen widths, improving speed.

B. They automatically add captions to images.

C. They convert images to black and white on small screens.

D. They disable images on mobile devices to save data.

Solution

1. Step 1: Understand responsive images purpose

   Responsive images adjust to screen size to load faster and look better.

2. Step 2: Identify Next.js Image component benefit

   Next.js Image component helps load the right image size automatically.

3. Final Answer:

   They load the right image size for different screen widths, improving speed. -> Option A

4. Quick Check:

   Responsive images = load right size fast [OK]

Hint: Responsive images adapt size to screen for speed [OK]

Common Mistakes:

• Thinking responsive images add captions automatically
• Believing images turn black and white on small screens
• Assuming images are disabled on mobile devices

2. Which is the correct way to import and use the Next.js Image component for responsive images?

easy

A. import Image from 'next/image';

B. import { Image } from 'react';

C. import Img from 'next/image';

D. import Image from 'next/image';

Solution

1. Step 1: Check import syntax

   Next.js Image is imported as default from 'next/image'. So, import Image from 'next/image' is correct.

2. Step 2: Check usage with required props

   Image requires src, width, height, and alt for accessibility and layout.

3. Final Answer:

   import Image from 'next/image'; <Image src='/pic.jpg' width={500} height={300} alt='pic' /> -> Option A

4. Quick Check:

   Correct import + width/height + alt = import Image from 'next/image'; [OK]

Hint: Next.js Image needs import, src, width, height, alt [OK]

Common Mistakes:

• Importing Image from 'react' instead of 'next/image'
• Omitting width and height props
• Using wrong component name like Img

3. What will be the behavior of this Next.js Image component?

import Image from 'next/image';
export default function Photo() {
  return (
    <Image
      src='/photo.jpg'
      alt='A photo'
      sizes='(max-width: 600px) 100vw, 50vw'
      width={800}
      height={600}
    />
  );
}

medium

A. Loads image only on screens wider than 600px.

B. Always loads image at 800x600 pixels regardless of screen size.

C. Throws an error because sizes prop is invalid.

D. Loads 100% viewport width image on screens 600px or smaller, else 50% viewport width.

Solution

1. Step 1: Understand sizes prop usage

   The sizes prop defines image display width based on screen width media queries.

2. Step 2: Interpret sizes value

   For screens max 600px wide, image uses 100vw (full viewport width). Otherwise, 50vw (half viewport width).

3. Final Answer:

   Loads 100% viewport width image on screens 600px or smaller, else 50% viewport width. -> Option D

4. Quick Check:

   Sizes prop controls image width by screen size [OK]

Hint: Sizes prop sets image width per screen size [OK]

Common Mistakes:

• Thinking sizes sets image pixel dimensions directly
• Assuming sizes prop causes error
• Believing image loads only on wide screens

4. Identify the error in this Next.js Image usage:

import Image from 'next/image';
export default function Banner() {
  return (
    <Image
      src='/banner.png'
      alt='Banner'
      width='100%'
      height='300'
    />
  );
}

medium

A. alt text is missing.

B. src path must be an external URL.

C. width should be a number, not a string with '%'.

D. height cannot be set with a number.

Solution

1. Step 1: Check width prop type

   Next.js Image expects width as a number (pixels), not a string with '%'.

2. Step 2: Verify other props

   alt is present, src can be local path, height as number is valid.

3. Final Answer:

   width should be a number, not a string with '%'. -> Option C

4. Quick Check:

   Width must be numeric pixels [OK]

Hint: Width and height props must be numbers, not strings [OK]

Common Mistakes:

• Using percentage strings for width or height
• Thinking alt text is optional
• Believing src must be external URL

5. You want to optimize images for a blog with different screen sizes. Which approach correctly uses Next.js Image to load responsive images with accessibility and performance in mind?

hard

A.

B.

C.

D.

Solution

1. Step 1: Check alt text for accessibility

   includes meaningful alt text 'Blog post', improving accessibility.

2. Step 2: Verify sizes and priority usage

   Sizes prop correctly sets image width for small and larger screens. Priority loads important images faster.

3. Step 3: Identify issues in other options

   A lacks alt text and reverses sizes logic, B has empty alt (bad for accessibility), D uses invalid string props for width/height.

4. Final Answer:

   <Image src='/post.jpg' alt='Blog post' width={1200} height={800} sizes='(max-width: 768px) 100vw, 50vw' priority /> -> Option B

5. Quick Check:

   Alt + sizes + priority = best practice [OK]

Hint: Use alt text, sizes, and priority for best responsive images [OK]

Common Mistakes:

• Leaving alt text empty
• Using invalid width/height values
• Incorrect sizes media query order