How to Optimize Google Maps Rendering in React Using React.memo

Описание: Learn how to prevent unnecessary re-renders of your Google Maps component in a React application using `React.memo`. Enhance performance and user experience in your app!
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How to Optimize Google Maps Rendering in React Using React.memo

In a React application, unnecessary re-renders can significantly degrade performance, especially when dealing with components like maps, which may be resource-intensive. If you're experiencing re-renders of your Google Maps component every time the state of the parent component changes—even when those changes are irrelevant to the map—you’re not alone. This post will guide you step-by-step on how to optimize your Google Maps component using React.memo to prevent these unwanted re-renders.

The Problem: Unnecessary Re-renders

When integrating Google Maps into our React application, we encountered an issue: the map component re-renders every time we update the parent component's state. Here’s a brief overview of the relevant code from the parent component:

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In this scenario, the MyMap component (which wraps the Google Maps implementation) is re-invoked every time the setPhone state changes in the parent component. This is inefficient and can lead to a laggy user experience.

The Solution: Using React.memo Correctly

Understanding React.memo

React.memo is a Higher-Order Component (HOC) designed to optimize functional components by memoizing their output. This means that if the component's props do not change, React will skip rendering the component altogether, thus avoiding unnecessary operations.

Implementing React.memo

In your case, even though you wrapped your Map component in React.memo, the issue arises due to the way your TabPanel is structured. The TabPanel component is defined inside the CompanyDepotsPopup component, which causes a new instance of TabPanel to be created on each render of CompanyDepotsPopup. This leads to re-renders of MyMap, even when its props remain unchanged.

Here’s how to fix it:

Move the TabPanel component outside of the CompanyDepotsPopup function.

[[See Video to Reveal this Text or Code Snippet]]

Modify your parent component to reference the external TabPanel.

[[See Video to Reveal this Text or Code Snippet]]

Why This Works

By moving TabPanel outside of CompanyDepotsPopup, you create a single instance of TabPanel. This means MyMap will not get remounted every time CompanyDepotsPopup updates; instead, it will only re-render when its props actually change, significantly improving performance.

Conclusion

In React, performance issues like unnecessary re-renders can make a noticeable difference in user experience, especially with resource-heavy components like Google Maps. By carefully utilizing React.memo and understanding how component instances are created, we can create a more efficient application.

With these changes, your Google Maps component should no longer re-render unnecessarily! Remember, if you're ever unsure whether a component should render again, consider whether its props are truly changing.

By adopting this strategy, you not only improve your app’s responsiveness but also foster a more seamless interaction for your users.