Solving the component flickering Issue with React-Query in Context API

Описание: Learn how to use `keepPreviousData` option in React-Query to prevent component flickering and enhance user experience while making queries.
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Solving the component flickering Issue with React-Query in Context API

When working with React applications that use context API and react-query, developers may encounter an issue where components flicker due to state changes and data fetching delays. This post explores this problem in detail and provides a clear solution to ensure a smooth user experience.

Understanding the Flickering Issue

The flickering issue arises in scenarios where:

The user interacts with a form and makes a selection using a dropdown.

This selection updates the context API, which then triggers a re-render of the parent component.

As a result, a mutation is fired, and a new query is made to fetch updated data.

Key Steps in the Process:

User selects an option.

Context API updates.

Parent component re-renders.

A mutation is triggered.

Flickering occurs as the component waits for the new data.

The flickering happens particularly when the component tries to use a value before the query has completed fetching new data, leading to undefined values being passed to components.

Common Symptoms

The component displays a value, then switches to undefined, and finally retrieves the new value after the data fetching is complete.

The user experience is disrupted due to these brief moments of inconsistency, which can be frustrating.

Proposed Solution: Using keepPreviousData

To address this issue, we can leverage the keepPreviousData option provided by react-query. Here’s how this works:

How It Works

keepPreviousData: This option allows react-query to retain the data from the previous query even when the query key changes.

When a new query is initiated, instead of showing undefined, you will still see the data from the previous query until the new data arrives.

You will also receive an isPreviousData: true flag, which can be used to manage loading states or conditional rendering.

Implementation Steps

Here’s how to apply the keepPreviousData option in your component:

Modify Your Query Hook: Update your product query to include the keepPreviousData option.

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

Update Your Component Rendering: Check the data and the isPreviousData flag to ensure your component behaves correctly during the transition between states.

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

In this setup, if the new data isn't available yet, the component will show the previous value instead of going through a flickering state of undefined.

Benefits

Improved User Experience: By keeping the previous data, users won’t notice the delays, making the interface feel more responsive and reliable.

Less Complexity: The need to implement local state or ref hooks to manage previous values is eliminated, simplifying your component logic significantly.

Conclusion

When working with state management and data fetching, it’s essential to ensure a smooth user experience. The keepPreviousData option in react-query provides an effective way to handle component flickering. By intelligently managing the query's state, we can maintain the flow of data without interrupting the user interaction.

For more complex queries where context changes frequently, consider using this option to manage your state and keep your components rendering smoothly.



Feel free to experiment with this solution and upgrade your React components’ performance while utilizing context API effectively!