Animated.Value and Animated.timing in React Native - UI Render Trace

Component - Animated.Value and Animated.timing

This React Native component shows how to animate a box moving horizontally using Animated.Value to hold the animation state and Animated.timing to change that value smoothly over time.

When you press the button, the box slides from the center to the right across the screen.

Widget Tree

View
├─ Animated.View
└─ Button

The root View holds two children: an Animated.View that is the moving box, and a Button that triggers the animation when pressed. The Animated.View uses the animated value to update its horizontal position.

Render Trace - 3 Steps

Step 1: View

Step 2: Animated.View

Step 3: Button

State Change - Re-render

Trigger:User presses the 'Move Box' button

Before

animatedValue is 0, so the box is centered horizontally

→

After

animatedValue animates to 200 over 1 second, moving the box right

Re-renders:Animated.View re-renders continuously during animation to update position

UI Quiz - 3 Questions

What does Animated.Value represent in this component?

A A number that changes over time to animate the box position

B A static color value for the box

C A function to handle button presses

D A style property for the button

Key Insight

Using Animated.Value with Animated.timing lets you smoothly change UI properties over time. The animated value drives the visual changes, and React Native efficiently updates only the parts that depend on it, creating smooth animations without blocking the app.