Drag and drop functionality is a common feature in many web applications. To implement droppable elements, we can create a custom React hook called useDroppable. This hook will handle the logic for making an element droppable and provide us with the necessary state and callbacks.

In this tutorial, we will walk through the steps of creating the useDroppable hook using React and TypeScript.

Table of Contents

• Setting up the Project
• Creating the useDroppable Hook
• Adding Droppable Functionality to Elements
• Using the useDroppable Hook
• Conclusion

Setting up the Project

Before we start, make sure you have a React project set up with TypeScript. You can create one using create-react-app:

npx create-react-app my-app --template typescript

Once your project is set up, navigate to the project directory:

cd my-app

Creating the useDroppable Hook

Start by creating a new file called useDroppable.ts in the src folder. This file will contain our custom hook code.

import { useState, useEffect, useDrag } from 'react';

const useDroppable = () => {
  const [isOver, setIsOver] = useState(false);

  const handleDragEnter = (event: DragEvent) => {
    event.preventDefault();
    setIsOver(true);
  };

  const handleDragLeave = () => {
    setIsOver(false);
  };

  const handleDrop = () => {
    setIsOver(false);
  };

  useEffect(() => {
    document.addEventListener('dragenter', handleDragEnter);
    document.addEventListener('dragleave', handleDragLeave);
    document.addEventListener('drop', handleDrop);

    return () => {
      document.removeEventListener('dragenter', handleDragEnter);
      document.removeEventListener('dragleave', handleDragLeave);
      document.removeEventListener('drop', handleDrop);
    };
  }, []);

  return { isOver };
};

export default useDroppable;

Here, we import the necessary React hooks to handle state and effects. The useDroppable hook sets up event listeners for drag and drop events and updates the isOver state based on these events. We return the isOver value as part of the hook’s return object.

Adding Droppable Functionality to Elements

To make an element droppable, we will use the useDroppable hook and attach the necessary event handlers to the element.

import React from 'react';
import useDroppable from './useDroppable';

const DroppableElement: React.FC = () => {
  const { isOver } = useDroppable();

  const handleDragOver = (event: React.DragEvent<HTMLDivElement>) => {
    event.preventDefault();
  };

  return (
    <div
      onDragOver={handleDragOver}
      style=
    >
      Droppable Element
    </div>
  );
};

export default DroppableElement;

In this example, we create a DroppableElement component that uses the useDroppable hook to enable droppable functionality. We attach the handleDragOver event handler to the element and conditionally set the background color based on the isOver state.

Using the useDroppable Hook

To use the useDroppable hook, import it into your desired component and invoke it.

import React from 'react';
import DroppableElement from './DroppableElement';

const App: React.FC = () => {
  return (
    <div>
      {/* Other components */}
      <DroppableElement />
    </div>
  );
};

export default App;

Now, the DroppableElement component will have droppable functionality enabled.

Conclusion

By creating the custom useDroppable hook, we abstracted away the drag and drop logic and made it reusable. This hook can be used to implement droppable elements in different parts of our application, providing a clean and modular approach.

Remember to check for browser compatibility when using drag and drop functionality, as some older browsers may not support all features.

That’s it! You now have a custom useDroppable hook for implementing droppable elements in React. Happy coding!

#react #typescript