In this post, we will see how to implement drag and drop functionality in browsers using the native drag and drop interface in HTML5.
The idea is simple:
<div className="flex gap-8"> <div id="box1" className="w-[300px] h-[300px] border border-black flex items-center justify-center" /> <div id="box2" className="w-[300px] h-[300px] border border-black flex items-center justify-center" /> </div>
These two boxes will serve as our "drop zones." The user will be able to drag an item from one box and drop it into the other.
<div id="box1" className="w-[300px] h-[300px] border border-black flex items-center justify-center" /> <div id="draggable1" className="w-[50px] h-[50px] bg-red-500 cursor-move" /> </div>
This red square will be the item that can be dragged between the boxes.
To make an element draggable, we need to add the draggable attribute to it and handle the dragstart event.
The dragstart event will trigger when the user starts dragging the item. Here’s how we can implement it:
const handleOnDragStart = (event) => { event.dataTransfer.setData("text/plain", event.target.id); };
In this function, we use event.dataTransfer.setData() to store the ID of the dragged element. This ID will later help us identify which element was dragged and where it needs to be dropped.
Next, update the draggable1 div to make it draggable and add the onDragStart event handler:
<div id="draggable1" className="w-[50px] h-[50px] bg-red-500 cursor-move" draggable="true" onDragStart="{handleOnDragStart}" />
const handleOnDrop = (event) => { event.preventDefault(); const data = event.dataTransfer.getData("text/plain"); event.target.appendChild(document.getElementById(data)); }; const handleDragOver = (event) => { event.preventDefault(); };
Finally, apply these event handlers to the boxes:
<div id="box1" onDrop="{handleOnDrop}" onDragOver="{handleDragOver}" className="w-[300px] h-[300px] border border-black flex items-center justify-center" > <div id="draggable1" className="w-[50px] h-[50px] bg-red-500 cursor-move" draggable="true" onDragStart="{handleOnDragStart}" /> </div> <div id="box2" onDrop="{handleOnDrop}" onDragOver="{handleDragOver}" className="w-[300px] h-[300px] border border-black flex items-center justify-center" />
You can add visual cues to highlight when the drag operation is in progress. We will reduce the opacity of the component.
This can be done by tracking when the drag operation is being performed in a state variable and changing the opacity.
This is how your react component should look like
<p>import { useState } from "react";</p> <p>const SimpleDragDrop = () => {<br> const [isDragging, setIsDragging] = useState(false);</p> <p>const handleOnDragStart = (event) => {<br> setIsDragging(true);<br> event.dataTransfer.setData("text/plain", event.target.id);<br> };</p> <p>const handleOnDrop = (event) => {<br> event.preventDefault();<br> setIsDragging(false);<br> const data = event.dataTransfer.getData("text/plain");<br> event.target.appendChild(document.getElementById(data));<br> };</p> <p>const handleDragOver = (event) => {<br> event.preventDefault();<br> };</p> <p>return (<br> <div className="flex gap-8"><br> <div<br> id="box1"<br> onDrop={handleOnDrop}<br> onDragOver={handleDragOver}<br> className="flex h-[300px] w-[300px] items-center justify-center border border-main"<br> ><br> <div<br> id="draggable1"<br> className={h-[50px] w-[50px] cursor-move bg-red-500 </span><span class="p">${</span><span class="nx">isDragging</span> <span class="p">?</span> <span class="dl">"</span><span class="s2">opacity-50</span><span class="dl">"</span> <span class="p">:</span> <span class="dl">"</span><span class="s2">opacity-100</span><span class="dl">"</span><span class="p">}</span><span class="s2">}<br> draggable={true}<br> onDragStart={handleOnDragStart}<br> /><br> </div><br> <div<br> id="box2"<br> onDrop={handleOnDrop}<br> onDragOver={handleDragOver}<br> className="flex h-[300px] w-[300px] items-center justify-center border border-main"<br> /><br> </div><br> );<br> };</p> <p>export default SimpleDragDrop;</p>
Live Demo
This example demonstrates how easy it is to implement drag-and-drop functionality with just a few lines of code. Feel free to expand on this by adding more drag-and-drop targets or customizing the appearance and behavior of the elements further!
Original Post
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