React Native’s Animation API library can help you create dynamic, fluid animations with little effort.
Learn how to create animations with spring-like effects, then learn how to control their duration and speed, and apply them to real-world scenarios.
What are dynamic animations?
Dynamic animations are animations where the movements of the animated objects are not pre-programmed. You can start them in response to user interaction or changes in the environment. The technique is most popular in video game animation, social media applications, or other forms of interactive media.
Dynamic animations can provide a more immersive and engaging experience for users, as it allows for unpredictable and responsive movements that can change based on a number of factors.
Animations in mobile apps have become more and more complex over the years. React Native’s default animated API has been upgraded to accommodate these complexities. The Animated.spring() method provided by the API can animate React Native objects, creating a dynamic effect.
Control animation
When using the Animated.spring() method, you have control over the animation to make sure it behaves the way you want. Animated provides a set of methods to manually control and manipulate your React Native animations.
One of those methods is stop(), which stops the animation at its current value. This method is useful when you need to cancel or reset an animation to its initial state.
Note how you can use the setValue() method to reset the status value to its initial state of 0.
Another method available to you is reset(), which returns the animation to its initial state. This method is useful when you need to restart the animation.
Real world applications
You can explore the practical use of the Animated.spring() method by creating a simple animation. A round ball will drop to a surface when a user interacts with it, then subsequently bounce back into the air. You should already have a React Native project that you can work with.
Use Animated.Value to create a position variable called position that will track the vertical position of the ball. Wrap the View component in Animated. View so that you can apply animations to it.
Use Animated.spring() to create an animation that will move the ball from a starting position of 0 to a final position of 300. Specify friction and tension values to control the ball’s bounce effect when useNativeDriver is set to true to improve performance.
This code wraps the Animated.View component in TouchableWithoutFeedback so that the animation is triggered when the user presses the ball. You can also trigger an animation when the component is mounted by calling the startAnimation() function inside React’s useEffect() hook.
With this code, you should have a falling ball animation created using animated.spring().
Dynamic animations in React Native
You’ve seen how to implement a falling ball animation using animated.spring(), but there are many other methods you can use to create dynamic animations.
For example, you can use Animated.spring() to create animations that simulate other physics-based movements, such as swinging or rotating objects.
By combining Animated.spring() with other animation functions, such as Animated.timing() or Animated.sequence() , you can create complex and seamless animations that enhance the user experience.
Animations can be a great way to improve the user experience of your React application. They can help make a conversation feel effortless, and can also provide visual feedback or draw attention to a particular element.
There are many ways you can work with CSS animations using React, from native solutions to third-party libraries.
Why use animations in React?
There are many reasons why you might want to use animations in your React application.
Animations can help make user interactions feel more natural and spontaneous. For example, if you’re using a Toggle component, you may want to animate the toggle button between “on” and “off” states. Another example is progress bars, you can create an animated progress bar for your React app’s pages.
Animations can provide visual feedback to the user. For example, if a user clicks a button, you might want to animate the button to indicate that the app has registered that action.
Animations can direct the user’s attention to a particular element. For example, if you have a modal dialog that appears on the screen, you may want to use animation to draw the user’s attention to it.
