dragon-drop-vue

Customizable native Vue3 drag-n-drop library with no dependencies. Includes Vue plugin that registers directives to configure draggable elements and drop zones.

This package is intended to just be a directive that wraps the browser's drag and drop API and combine it with Vue's reactive features. The actual HTML events are available in each of the event handler callbacks. It is recommended to still understand how the browser's API works to best decide how to wire-up the directives for your use case. MDN has a good primer on the browser API here.

Install

npm i dragon-drop-vue

Setup

import { createApp } from 'vue'
import App from './App.vue'
import { DragonDropVue } from 'dragon-drop-vue'

const dragonDropOptions = {
  dragOverDebounceMs: 300,
  debugLog: true,
}

createApp(App).use(DragonDropVue, dragonDropOptions)

Usage

<template>
  <main>
    <template v-for="column in columns">
      <div v-drop="{ dragData: column, onDragEnter: onDragEnter, onDrop: onDrop }"></div>
      <div v-drag="{ dragData: column, dragImage: dragImage, onDragStart: onDragStart }">{{ column }}</div>
    </template>
  </main>
</template>

<script setup lang="ts">
import { ref } from 'vue'
import type { DragonDropVueDragOptions, DragonDropVueOptions } from 'dragon-drop-vue'

const columns = ref([0, 1, 2, 3, 4, 5, 6])
const dragging = ref<number | undefined>(undefined)

const image = new Image()
image.src = 'dragon.png'
const dragImage = {
  image,
  xOffset: 30,
  yOffset: 0,
}

function onDragStart(domEl: HTMLElement, dragEvent: DragEvent, dragOptions: DragonDropVueDragOptions<number>, options: DragonDropVueOptions) {
  dragging.value = dragOptions.dragData
}

function onDragEnter(domEl: HTMLElement, dragEvent: DragEvent, dragOptions: DragonDropVueDragOptions<number>, options: DragonDropVueOptions) {
  // do not allow a draggable element to be dropped on itself
  var dragIndex = this.dragging ?? 0
  var dropIndex = dragOptions.dragData ?? 0
  return dragIndex !== dropIndex
}

function onDrop(domEl: HTMLElement, dragEvent: DragEvent, dragOptions: DragonDropVueDragOptions<number>, options: DragonDropVueOptions) {
  // implement drop behavior
}
</script>

Plugin Options (i.e. DragonDropVueOptions)

Property	Type	Description
debugLog	boolean or undefined	Print additional debugging information to the console. All drag and drop events are printed. This also enables the Info log level of native-event-vue.
dragDirectiveName	string or undefined	Optionally specify what to register for the drag directive. By default this is drag and the directive would be v-drag.
dropDirectiveName	string or undefined	Optionally specify what to register for the drag directive. By default this is drop and the directive would be v-drop.
dragClass	string or undefined	Custom class that will be added to all elements with the drag directive. ddv-draggable is also always added.
dropClass	string or undefined	Custom class that will be added to all elements with the drop directive. ddv-dropzone is also always added.
draggingClass	string or undefined	Custom class that will be added to the element currently being dragged. ddv-dragging is also always added.
dragOverClass	string or undefined	Custom class that will added to the element currently being dragged over. ddv-ddv-dragging-over is also always added.
dragOverDebounceMs	number or undefined	Optionally override the debounce period for the dragover event. By default, this is set to 500ms. Setting this to 0 will turn off debouncing of the dragover event. This can also be overridden by passing the same option to the object bound to the drop directive. The directive value will take precedence.
dragOverDebounceMode	DebounceMode or undefined	Optionally override the debounce mode used to debounce the dragover event. By default, MaximumFrequency is used and this will debounce the event and only call the vent handler at most once during the debounce timeout. This can also be overridden by passing the same option to the object bound to the drop directive. The directive value will take precedence.

Directive Options (i.e. DragonDropVueDragOptions)

The same options interface is used for both the drag and drop directive but some event handlers on apply to one or the other.

The DragonDropVueDragOptions type has an optional type constraint for the type of the supplied drag data that will default to any.

All event handler properties are of the following type.

(domEl: HTMLElement, dragEvent: DragEvent, dragOptions: DragonDropVueDragOptions<T>, options: DragonDropVueOptions) => boolean | undefined

Property	Type	Description
dragData	Generic type constraint or any	Any piece of data to pass to each drag and drop event handler.
dragImage	DragonDropVueDragImageOptions	Optional drag image override.
onDragStart	Drag/drop event handler	dragstart event handler
onDragEnd	Drag/drop event handler	dragend event handler
onDragOver	Drag/drop event handler	dragover event handler
onDragEnter	Drag/drop event handler	dragenter event handler
onDragLeave	Drag/drop event handler	dragleave event handler
onDrop	Drag/drop event handler	drop event handler
dragOverDebounceMs	number or undefined	Optionally override the debounce period for the dragover event. By default, this is set to 500ms. Setting this to 0 will turn off debouncing of the dragover event. This will take precedence over the same option on the plugin options.
dragOverDebounceMode	DebounceMode or undefined	Optionally override the debounce mode used to debounce the dragover event. By default, MaximumFrequency is used and this will debounce the event and only call the vent handler at most once during the debounce timeout. This will take precedence over the same option on the plugin options.

Drag Data

When drag data is specified to the drag directive it is set on the data transfer of the browser events as JSON. The drop directive will also retrieve the drag data from the date transfer object, deserialize it and set it as the drag data on the options passed to the onDrop callback.

Vue Component as Drag Image

The drag directive contains the necessary boilerplate to take a Vue component definition and prop values to create an element to use as the drag image. It is also automatically removed from the DOM as part of onDrop handling.

<template>
  <main>
    <template v-for="column in columns">
      <div v-drop="{ dragData: column, onDragEnter: onDragEnter, onDrop: onDrop }"></div>
      <div v-drag="{ dragData: column, onDragStart: onDragStart }">{{ column }}</div>
    </template>
  </main>
</template>

<script setup lang="ts">
import { ref } from 'vue'
import type { DragonDropVueDragOptions, DragonDropVueOptions } from 'dragon-drop-vue'
import CustomComponent from '@/components/CustomComponent.vue'

const columns = ref([0, 1, 2, 3, 4, 5, 6])
const dragging = ref<number | undefined>(undefined)

function onDragStart(domEl: HTMLElement, dragEvent: DragEvent, dragOptions: DragonDropVueDragOptions<number>, options: DragonDropVueOptions) {
  dragging.value = dragOptions.dragData

  dragOptions.dragImage = {
    rootComponent: CustomComponent,
    rootComponentProps: { column: dragOptions.dragData },
  }
}
</script>

---

Release Notes

v2.1.1

• Rev development dependencies. This addresses the security vulnerabilities reported in package ip.

v2.1.0

• Fix for dragover event not getting preventDefault called on it when debounced to ensure the drop event fires.
• Update to v1.4.0 of native-event-vue
• Do not log updated lifecycle hooks when it did not result in the event handler being attached or detached.
• Remove drop handling in beforeMount and updated lifecycle hooks when the bound value changes to false
• Remove all classes and event handlers instead of just setting the draggable attribute to false when the drag directive binding is set to false

v2.0.0

• Migrate to native-event-vue to manage adding and removing HTML native events to DOM elements and leverage its debouncing capabilities on the dragover event.
• The dragover event is now debounced by default and the attached handler will only run at most once every 500ms. The debounce time and debounce mode can be configured on the plugin options.
• Additional source documentation.
• Automated tests

v1.2.0

• Add additional debug logging to track when directive lifecycle hooks fire and DOM state after processing.
• Add additional debug logging to track when HTML event handlers are added or removed.
• Improve debug log formatting.

v1.1.1

• Update development dependencies.

v1.1.0

• Add ability to specify a Vue component and property values for the drag image.
• Parse data transfer drag data from drop event and pass to onDrop via the drag options drag data if drag data does not already exist.

v1.0.0

• Plugin options can no longer be undefined. The default value is now an empty object.
• Requires node v18 or greater

v0.2.0

• Documentation update

v0.1.1

• improve plugin and directive typing

v0.1.0

• allow directive names to be overridden via plugin options

v0.0.4

• export DropEffect
• react to options changes that can turn draggable on/off

v0.0.3

• remove console.log

v0.0.2

• allow false to turn off drag and drop directives

v0.0.1

• Initial release