Animated API basics in React Native - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the purpose of the Animated API in React Native?

The Animated API helps create smooth and efficient animations in React Native apps, making UI elements move or change over time.

beginner

What is an Animated.Value in React Native?

Animated.Value is a special variable that holds a number which can change over time to drive animations.

beginner

How do you start an animation using the Animated API?

You use functions like Animated.timing() or Animated.spring() and then call .start() to begin the animation.

beginner

What does Animated.View do?

Animated.View is like a regular View but can accept animated styles to smoothly change its appearance or position.

intermediate

Why should animations use the Animated API instead of changing styles directly?

The Animated API runs animations on the native thread, making them smoother and more efficient than changing styles directly in JavaScript.

Which of these is used to create a changing numeric value for animation?

A Animated.Value

B Animated.View

C Animated.Style

D Animated.Component

Animated.Value holds the numeric value that changes during animation.

How do you start an animation with the Animated API?

A Call <code>Animated.start()</code>

B Call <code>.start()</code> on an animation object

C Set a style property directly

D Use <code>Animated.run()</code>

You create an animation like Animated.timing() and then call .start() on it.

Which component allows you to apply animated styles to a container?

A Animated.Container

B Animated.Text

C Animated.Style

D Animated.View

Animated.View is used to animate container views.

What is the benefit of using the Animated API over changing styles directly?

A It disables user interaction

B It uses less memory

C Animations run on the native thread for better performance

D It requires less code

The Animated API runs animations on the native thread, making them smoother.

Which method is commonly used to create a timing animation?

A Animated.timing()

B Animated.decay()

C Animated.spring()

D Animated.loop()

Animated.timing() creates animations that change values over a set duration.

Explain how to create a simple fade-in animation using the Animated API.

Think about changing opacity from 0 to 1 over time.

Describe why using Animated.View is important for animations in React Native.

Consider how it differs from a normal View.