Enhance your React Native Application Performance.
Various ways to improve the React Native Application performance
Part — 1 The Overview
Hi there! React Native is the most favored framework that delivers flexibility and adaptability, according to cross-platform app developers. This framework has built-in capabilities and has large community support to make the apps more useful as well as attractive.
However, there are certain drawbacks to this application architecture, especially when it comes to performance, You would be aware of the limited support for animation and the lack of parallel processing on this platform. These interactions may slow down the speed and have an impact on the performance as a whole.
The community is continuously working on improving its performance with various methods to make better architecture, multiple JS Engine support, and so on.
Let’s see how the performance drops before making any plans to improve it. Get started!
Top factor for the performance drop
When the same task is performed over and over again, it has a significant impact on the application’s performance. It is also affected when the component is used too heavily and re-rendered often.
- Over-rendering will significantly impact how well the application performs. The reason behind this is increasing in frame rates which affects the app speed.
- Unaware of the pros of memorization when dealing with static components.
- When huge quantities of data are loaded without pagination. It definitely makes a performance penalty.
- Running animations in the JS thread and ignoring the UI thread utilization.
- Not optimizing the image rendering.
These are the frequently used performance-dropping factors. Now Let’s see how to improve the app’s performance.
Top methods to fine-tune the app performance
To Avoid Unwanted Rendering, Use Memorization.
React library offers inbuild memorization features like
- useMemo()
- React.memo()
The useMemo Hook can be used to prevent costly, resource-intensive processes from running repeatedly.
If you use a React memo, React will skip rendering a component if its props have not changed. This can improve performance. We will see this memorization with examples in a separate blog.
Make faster App Launch
When it comes to app performance metrics, one of the most important factors is app launch speed — use Hermes.
You might think, what is Hermes?
Hermes is an Open source Javascript Engine which is specially designed for React Native apps. It improves the start-up time, decreased memory usage, and smaller app size. Now, Hermes is used as default by React Native. The primary reason is bytecode precompilation (Hermes Engine uses AOT (ahead-of-time compiler) rather than JIT (just in time), which means the bytecode conversion occurs at build time rather than run time. Hermes substantially boosts memory utilization and app launch speed. For more details click here.
Use the cached optimized image
For faster images, take advantage of community packages (such as react-native-fast-image). Each image in your collection is a new Image() instance. The sooner it reaches the loaded hook, the sooner your JavaScript thread will be free.
Avoid Using the Scroll View
ScrollView and FlatList are two methods for displaying lists in your application. This helps in the appearance of scrollable lists on the app interface.
Implementing ScrollView is easier, as it renders the list easily. The fact that you render every component is the only drawback to this component list view. The performance will be affected if the list contains unlimited views. It will make data handling more difficult and make the application run slower.
Instead of using ScrollView use Flatlist, which is well optimized and suitable for large lists of data. Also, try Shopify’s Flashlist which is more mature and optimized with higher frames per second.
Important note: Rendering large data cause a performance penalty, Make sure to use pagination for rendering a large list of data.
Utilize the Animations properly.
We’ve already talked about how animations might slow down your application. You may be able to avoid rendering complicated programs. You can utilize the nativeDriver method to assure the smooth rendering of animated apps.
The function makes sure that your animations are processed on the interface before passing them over the native bridge, as the name would imply. Your animation would run separately instead of through JavaScript threads.
React Native reanimated helps a lot when it comes to animations in React Native apps. Reanimated aims to provide ways of offloading animation and event-handling logic off of the JavaScript thread and onto the UI thread. These things are achieved by the Reanimated worklets which use a separate Javascript VM to run the animations smoothly.
Implement Memory Optimization
You must ensure that your app code is optimized in order to detect memory leaks and improve memory usage. Make sure that the console log is not included in the production version.
Conclusion
App performance is a crucial part of user experience. It is better to create a well-optimized application. This place, I believe, captured your interest.
So far, you’ve learned some basic techniques to optimize and improve your React Native performance. In the very next blog post, we will see in-depth optimization techniques with real-time examples. Until then, keep expecting the best from us. Bye-bye.
