Spinner components in Bootsrap - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a spinner component in Bootstrap?

A spinner component in Bootstrap is a small animated graphic that shows loading or processing activity to users, helping them know the app is working.

beginner

How do you create a simple spinner using Bootstrap?

Use the <div class='spinner-border' role='status'><span class='visually-hidden'>Loading...</span></div> code. This creates a circular spinner with accessible text.

intermediate

What role does role='status' play in spinner components?

It helps screen readers announce the spinner as a status message, improving accessibility for users who rely on assistive technology.

beginner

Name two types of spinners Bootstrap offers.

Bootstrap offers border spinners (a rotating border) and grow spinners (a growing and shrinking circle).

intermediate

How can you change the color of a Bootstrap spinner?

Add a color utility class like <code>text-primary</code>, <code>text-success</code>, or <code>text-danger</code> to the spinner element to change its color.

Which Bootstrap class creates a border spinner?

A spinner-border

B spinner-grow

C spinner-circle

D spinner-rotate

The class spinner-border creates a spinner with a rotating border.

What is the purpose of the <span class='visually-hidden'> inside a spinner?

A To add color to the spinner

B To show a tooltip on hover

C To provide accessible text for screen readers

D To animate the spinner

The visually-hidden class hides text visually but keeps it readable by screen readers.

Which attribute improves accessibility by indicating the spinner is a status message?

A tabindex='0'

B role='button'

C aria-hidden='true'

D role='status'

The role='status' tells assistive tech that the spinner is a live status update.

How do you make a spinner larger in Bootstrap?

A Add class <code>spinner-border</code> with custom CSS size

B Add inline style <code>font-size</code>

C Add class <code>spinner-lg</code>

D Add class <code>spinner-border-sm</code>

Bootstrap does not provide a built-in large spinner class, so you customize size with CSS on the spinner element.

Which spinner type grows and shrinks instead of rotating?

A spinner-border

B spinner-grow

C spinner-pulse

D spinner-fade

The spinner-grow class creates a spinner that grows and shrinks.

Explain how to create an accessible spinner component in Bootstrap.

Think about both the visual spinner and how screen readers understand it.

Describe how you can customize the appearance of Bootstrap spinners.

Consider color, size, and spinner style.

Practice

1. What is the main purpose of Bootstrap spinner components?

easy

A. To show a loading or processing state visually

B. To create navigation menus

C. To style buttons with colors

D. To add images to the page

Solution

1. Step 1: Understand spinner usage

   Spinners are used to indicate that something is loading or processing in the background.

2. Step 2: Identify spinner purpose in Bootstrap

   Bootstrap spinner components visually show this loading state to users.

3. Final Answer:

   To show a loading or processing state visually -> Option A

4. Quick Check:

   Spinner = Loading indicator [OK]

Hint: Spinners always mean loading or waiting [OK]

Common Mistakes:

• Thinking spinners are for decoration only
• Confusing spinners with buttons
• Using spinners for static images

2. Which of the following is the correct Bootstrap class to create a border spinner?

easy

A. spinner-grow

B. spinner-spin

C. spinner-border

D. spinner-circle

Solution

1. Step 1: Recall Bootstrap spinner classes

   Bootstrap provides two main spinner classes: spinner-border and spinner-grow.

2. Step 2: Identify the border spinner class

   The class spinner-border creates a spinner with a border style.

3. Final Answer:

   spinner-border -> Option C

4. Quick Check:

   Border spinner class = spinner-border [OK]

Hint: Border spinner always uses spinner-border class [OK]

Common Mistakes:

• Using spinner-grow for border spinner
• Typing class names incorrectly
• Confusing spinner classes with button classes

3. What will be the visible result of this code snippet?

<div class="spinner-grow text-primary" role="status">
  <span class="visually-hidden">Loading...</span>
</div>

medium

A. A growing spinner with blue color and hidden accessible text

B. A border spinner with red color and visible text

C. A static blue circle with visible 'Loading...' text

D. No spinner shown, only text visible

Solution

1. Step 1: Analyze spinner-grow and text-primary classes

   The spinner-grow class creates a growing spinner animation. The text-primary class applies Bootstrap's primary blue color.

2. Step 2: Understand role and visually-hidden span

   The role="status" helps screen readers. The span with visually-hidden hides the text visually but keeps it accessible.

3. Final Answer:

   A growing spinner with blue color and hidden accessible text -> Option A

4. Quick Check:

   spinner-grow + text-primary = blue growing spinner [OK]

Hint: spinner-grow + text-primary = blue growing spinner [OK]

Common Mistakes:

• Thinking text-primary changes text color only
• Expecting visible text from visually-hidden span
• Confusing spinner-grow with spinner-border

4. Identify the error in this spinner code:

<div class="spinner-border" aria-label="Loading">
  <span>Loading...</span>
</div>

medium

A. aria-label should be aria-labelledby

B. Incorrect class name spinner-border

C. Missing role="status" attribute for accessibility

D. Span should have class visually-hidden for screen readers

Solution

1. Step 1: Check accessibility best practices for spinners

   Bootstrap recommends adding a span with visually-hidden class inside spinners to provide accessible text for screen readers.

2. Step 2: Analyze given code

   The span inside the spinner lacks the visually-hidden class, so the text is visible visually, which is not ideal.

3. Final Answer:

   Span should have class visually-hidden for screen readers -> Option D

4. Quick Check:

   Accessible text inside spinner needs visually-hidden class [OK]

Hint: Use visually-hidden class on spinner text for accessibility [OK]

Common Mistakes:

• Omitting visually-hidden class
• Using aria-label instead of role
• Confusing aria-label with aria-labelledby

5. You want to create a spinner that grows in size and uses the Bootstrap danger color with accessible text. Which code snippet correctly achieves this?

hard

A. Loading...

B. Loading...

C. Loading...

D. Loading...

Solution

1. Step 1: Choose spinner-grow for growing animation

   The question asks for a spinner that grows in size, so spinner-grow is the correct class.

2. Step 2: Apply danger color and accessibility

   The text-danger class applies the red color. The role="status" and span with visually-hidden provide accessible loading text.

3. Step 3: Verify all requirements

   Loading... uses spinner-grow, text-danger, role="status", and hidden accessible text correctly.

4. Final Answer:

   <div class="spinner-grow text-danger" role="status"><span class="visually-hidden">Loading...</span></div> -> Option B

5. Quick Check:

   Growing spinner + danger color + accessible text =
   Loading...
   [OK]

Hint: spinner-grow + text-danger + visually-hidden span = correct combo [OK]

Common Mistakes:

• Using spinner-border instead of spinner-grow
• Missing role="status"
• Not hiding accessible text visually