gui/docs/ref/wails-v3/features/drag-and-drop/html.mdx
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Co-Authored-By: Virgil <virgil@lethean.io>
2026-03-14 10:26:36 +00:00

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---
title: HTML Drag & Drop
description: Drag and drop elements within your application
sidebar:
order: 2
---
HTML5 drag-and-drop lets users drag elements within your app's UI - for example, reordering a list or moving items between columns. This is standard web functionality that works in Wails without any special setup.
## Make an Element Draggable
By default, most elements can't be dragged. To make an element draggable, add `draggable="true"`:
```html
<div class="item" draggable="true">Drag me</div>
```
The element will now show a drag preview when the user clicks and drags it.
## Define a Drop Zone
Elements don't accept drops by default. To make an element accept drops, you need to cancel the default behaviour on `dragover`:
```html
<div class="drop-zone" id="target">Drop here</div>
<script>
const target = document.getElementById('target');
target.addEventListener('dragover', (e) => {
e.preventDefault(); // Allow the drop
});
target.addEventListener('drop', (e) => {
e.preventDefault();
// Handle the drop
});
</script>
```
Calling `preventDefault()` on `dragover` is required - it signals that this element accepts drops. Without it, the drop event won't fire.
## Style Drag Hover
To show users where they can drop, add visual feedback when dragging over a drop zone. The `dragenter` event fires when something enters the zone, and `dragleave` fires when it leaves:
```css
.drop-zone {
border: 2px dashed #ccc;
padding: 40px;
transition: all 0.2s ease;
}
.drop-zone.drag-over {
border-color: #007bff;
background-color: rgba(0, 123, 255, 0.1);
}
```
```javascript
const target = document.getElementById('target');
target.addEventListener('dragenter', () => {
target.classList.add('drag-over');
});
target.addEventListener('dragleave', () => {
target.classList.remove('drag-over');
});
target.addEventListener('drop', (e) => {
e.preventDefault();
target.classList.remove('drag-over');
// Handle the drop
});
```
Note: `dragleave` also fires when entering a child element, which can cause flickering. The complete example below shows how to handle this.
## Complete Example
A task list where items can be dragged between priority columns. This tracks the dragged element in a variable, which is the simplest approach when everything is on the same page:
```html
<div class="tasks">
<div class="item" draggable="true">Fix login bug</div>
<div class="item" draggable="true">Update docs</div>
<div class="item" draggable="true">Add dark mode</div>
</div>
<div class="columns">
<div class="drop-zone" data-priority="high">
<h3>High Priority</h3>
<ul></ul>
</div>
<div class="drop-zone" data-priority="low">
<h3>Low Priority</h3>
<ul></ul>
</div>
</div>
<script>
let draggedItem = null;
// Track which item is being dragged
document.querySelectorAll('.item').forEach(item => {
item.addEventListener('dragstart', () => {
draggedItem = item;
item.classList.add('dragging');
});
item.addEventListener('dragend', () => {
item.classList.remove('dragging');
});
});
// Handle drops on each zone
document.querySelectorAll('.drop-zone').forEach(zone => {
zone.addEventListener('dragover', (e) => {
e.preventDefault();
});
zone.addEventListener('dragenter', () => {
zone.classList.add('drag-over');
});
zone.addEventListener('dragleave', (e) => {
// Only remove the class if we're leaving the zone entirely,
// not just entering a child element
if (!zone.contains(e.relatedTarget)) {
zone.classList.remove('drag-over');
}
});
zone.addEventListener('drop', (e) => {
e.preventDefault();
zone.classList.remove('drag-over');
if (draggedItem) {
const li = document.createElement('li');
li.textContent = draggedItem.textContent;
zone.querySelector('ul').appendChild(li);
draggedItem.remove();
}
});
});
</script>
<style>
.item {
padding: 12px 16px;
background: #f0f0f0;
margin: 8px 0;
border-radius: 8px;
cursor: grab;
}
.item.dragging {
opacity: 0.5;
}
.drop-zone {
min-height: 150px;
border: 2px dashed #ccc;
border-radius: 8px;
padding: 15px;
transition: all 0.2s ease;
}
.drop-zone.drag-over {
border-color: #007bff;
background: rgba(0, 123, 255, 0.1);
}
</style>
```
## Combining with File Drop
If your app uses both HTML drag-and-drop and [File Drop](./files), your HTML drop zones will also receive events when users drag files from the operating system. To prevent confusion, filter out file drags in your handlers:
```javascript
zone.addEventListener('dragenter', (e) => {
// Ignore external file drags
if (e.dataTransfer?.types.includes('Files')) return;
zone.classList.add('drag-over');
});
zone.addEventListener('dragover', (e) => {
// Ignore external file drags
if (e.dataTransfer?.types.includes('Files')) return;
e.preventDefault();
});
zone.addEventListener('drop', (e) => {
// Ignore external file drags
if (e.dataTransfer?.types.includes('Files')) return;
e.preventDefault();
zone.classList.remove('drag-over');
// Handle the internal drop
});
```
The `dataTransfer.types` array contains `'Files'` when the user is dragging files from the OS, but contains types like `'text/plain'` for internal HTML drags. This lets you distinguish between the two.
## Passing Data with dataTransfer
The example above tracks the dragged element in a JavaScript variable. This works well when everything is on the same page. But if you need to drag between iframes or pass data that isn't tied to a DOM element, use the `dataTransfer` API:
```javascript
// When drag starts, store data
item.addEventListener('dragstart', (e) => {
e.dataTransfer.setData('text/plain', item.id);
});
// When dropped, retrieve the data
target.addEventListener('drop', (e) => {
e.preventDefault();
const itemId = e.dataTransfer.getData('text/plain');
const item = document.getElementById(itemId);
// Move or copy the item
});
```
The data is stored as strings, so you'll need to serialize objects with `JSON.stringify()` if needed.
## Next Steps
- [File Drop](./files) - Accept files from the operating system
- [MDN Drag and Drop API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_Drag_and_Drop_API) - Full browser API reference