Crossfade for list items in Svelte - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the purpose of the crossfade function in Svelte?

The crossfade function creates smooth transitions between elements entering and leaving the DOM, making list items fade and move gracefully instead of appearing or disappearing abruptly.

beginner

How do you import the <code>crossfade</code> function in a Svelte component?

You import it from <code>svelte/animate</code> like this: <br><code>import { crossfade } from 'svelte/animate';</code>

intermediate

What are the two functions returned by crossfade() and what are they used for?

The crossfade() function returns two functions: send and receive. <br>- send is used on elements leaving the DOM to animate their exit.<br>- receive is used on elements entering the DOM to animate their entrance.

beginner

Why do list items need a unique key when using crossfade in Svelte?

A unique key helps Svelte track which items are entering or leaving so it can match them and apply the crossfade animation correctly between the old and new elements.

intermediate

How can you customize the duration of the crossfade animation in Svelte?

You can pass options to <code>crossfade()</code>, such as <code>duration</code>, to control how long the animation lasts. For example:<br><code>const [send, receive] = crossfade({ duration: d => Math.sqrt(d * 200) });</code>

What does the crossfade function in Svelte help you do?

A Sort list items alphabetically

B Create a fade effect only when hovering over elements

C Animate elements smoothly when they enter or leave a list

D Change the color of list items on click

Crossfade creates smooth animations for elements entering or leaving, making transitions look natural.

Which two functions does crossfade() return?

A send and receive

B fadeIn and fadeOut

C enter and leave

D start and stop

The crossfade function returns send (for leaving elements) and receive (for entering elements) functions.

Why is it important to use a unique key on list items when using crossfade?

A To improve page loading speed

B To disable animations

C To change the font style

D To help Svelte match items for animation

Unique keys let Svelte track which items correspond between old and new lists for smooth animation.

Where do you import the crossfade function from in Svelte?

A 'svelte/animate'

B 'svelte/store'

C 'svelte/internal'

D 'svelte/transition'

crossfade is part of the animate module in Svelte.

How can you change the speed of the crossfade animation?

A By changing the CSS color property

B By passing a duration option to crossfade()

C By adding a delay in the HTML

D By using a different key

You customize animation timing by setting the duration option in crossfade.

Explain how the crossfade function works in Svelte to animate list items when they change.

Think about how elements leave and enter the list and how Svelte matches them.

Describe the steps to add a crossfade animation to a list of items in a Svelte component.

Focus on imports, function usage, and keys.