How to use the useInfiniteQuery hook for paginated infinite scroll with React-Query

To implement paginated infinite scroll with React-Query using the useInfiniteQuery hook, you can follow these steps:

1. Install React-Query: First, make sure you have React-Query installed in your project. You can install it via npm or yarn:

   csharpCopy code
   npm install react-query
   // or
   yarn add react-query
   

2. Set Up Your API Functions: You need to define a function to fetch your paginated data from the server. This function should accept a pageParam parameter that specifies the page number to fetch.

3. Use useInfiniteQuery Hook: In your React component, import useInfiniteQuery from 'react-query'. Then, use it to fetch and manage paginated data.

Here's an example implementation:

jsxCopy code
import React from 'react';
import { useInfiniteQuery } from 'react-query';

const fetchUsers = async (key, page = 1) => {
  const response = await fetch(`https://api.example.com/users?page=${page}`);
  if (!response.ok) {
    throw new Error('Network response was not ok');
  }
  return response.json();
};

const UsersList = () => {
  const {
    data,
    fetchNextPage,
    hasNextPage,
    isFetching,
    isFetchingNextPage,
    error,
  } = useInfiniteQuery('users', fetchUsers, {
    getNextPageParam: (lastPage, allPages) => {
      // Return the next page number or null if no more pages left
      return lastPage.page < lastPage.totalPages ? lastPage.page + 1 : null;
    },
  });

  if (error) return <div>Error: {error.message}</div>;

  return (
    <div>
      {data.pages.map(pageData => (
        <React.Fragment key={pageData.page}>
          {pageData.users.map(user => (
            <div key={user.id}>{user.name}</div>
          ))}
        </React.Fragment>
      ))}
      {isFetching && <div>Loading...</div>}
      {hasNextPage && (
        <button
          onClick={() => fetchNextPage()}
          disabled={isFetchingNextPage}
        >
          {isFetchingNextPage ? 'Loading more...' : 'Load More'}
        </button>
      )}
    </div>
  );
};

export default UsersList;

In this example:

• We have a fetchUsers function that fetches users from an API endpoint. It takes a page parameter indicating the page number to fetch.
• We use the useInfiniteQuery hook to fetch paginated data. We pass it the key 'users' to identify this query, the fetchUsers function, and a getNextPageParam function that tells React-Query how to determine the next page number.
• We render the fetched users and provide a button to load more pages if there are more pages available.

Make sure to adjust the API endpoint and data structure according to your backend implementation.