Prompt Title: Scroll API calls React

To implement the functionality of making a new API call and setting the received data into the dropdown when it is scrolled to the bottom in a React component using TypeScript, you can follow the following steps:

1. Import the necessary dependencies:

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import { useState, useEffect, useRef } from "react";

2. Define a state variable to store the data that you want to show in the dropdown:

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const [dropdownData, setDropdownData] = useState<any[]>([]);

3. Define a reference to the dropdown element using the useRef hook:

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const dropdownRef = useRef<HTMLSelectElement>(null);

4. Define a function to make the API call and update the state variable with the received data:

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const fetchData = async () => {
  // Make the API call here
  const response = await fetch("your-api-url");
  const data = await response.json();

  // Update the state variable with the received data
  setDropdownData((prevData) => [...prevData, ...data]);
};

5. Use the useEffect hook to add an event listener to the dropdown element and check if it is scrolled to the bottom:

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useEffect(() => {
  const dropdownElement = dropdownRef.current;

  const handleScroll = () => {
    if (
      dropdownElement &&
      dropdownElement.scrollHeight - dropdownElement.scrollTop ===
        dropdownElement.clientHeight
    ) {
      fetchData();
    }
  };

  dropdownElement?.addEventListener("scroll", handleScroll);

  return () => {
    dropdownElement?.removeEventListener("scroll", handleScroll);
  };
}, []);

In this code, the handleScroll function is called when the dropdown element is scrolled. It checks if the element is scrolled to the bottom by comparing the sum of the scrollTop and clientHeight properties with the scrollHeight property of the element. If it is scrolled to the bottom, the fetchData function is called to make a new API call and update the state variable with the received data.

6. Finally, render the dropdown element and pass the dropdownRef reference to it:

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return (
  <select ref={dropdownRef}>
    {dropdownData.map((item) => (
      <option key={item.id} value={item.value}>
        {item.label}
      </option>
    ))}
  </select>
);

This code will render a dropdown element with the options from the dropdownData state variable. As the user scrolls to the bottom of the dropdown, new data will be fetched and added to the dropdownData state variable, and the options in the dropdown will be updated accordingly.