DragDropContainer and DropTarget

Live demo: peterh32.github.io/react-drag-drop-container

Make something draggable:

import { DragDropContainer } from 'react-drag-drop-container';

<DragDropContainer>
    <div>Look, I'm Draggable!</div>
</DragDropContainer>

Set up a drop target:

import { DragDropContainer, DropTarget } from 'react-drag-drop-container';

<DragDropContainer targetKey="foo" >
    <div>Drag Me!</div>
</DragDropContainer>

<DropTarget targetKey="foo" >
    <p>I'm a valid drop target for the object above since we both have the same targetKey!</p>
</DropTarget>

Wire up events and data on the DragDropContainer:

<DragDropContainer targetKey="foo" dragData={some object} onDragStart={some method} onDrop={some method}...>
    <div>Drag Me!</div>
</DragDropContainer>

dragData: Data to pass to the drop target.

onDragStart, onDrag, onDragEnd: Callbacks during the drag process. These are passed the dragData object set above. onDrag and onDragEnd are also passed dropTarget (the DOM element we're currently over), x, and y (current position).

onDrop: Callback that fires after a successful drop on a compatible target. It gets passed an event object that contains all this:

{
    dropData: [whatever you put in the dropData property for the DropTarget]
    dropElem: [reference to the DOM element being dragged]
    sourceElem: [reference to the DragDropContainer DOM element]
    target: [reference to the DropContainer DOM element]
}

Wire up events and data in the DropTarget:

<DropTarget targetKey="foo" dropData={some object} onDragEnter={highlight method} onDragLeave={unHighlight} onHit={some function}>
    <p>Drop something on me</p>
</DropTarget>

dropData: Data to pass back to the DragDropContainer.

onDragEnter, onDragLeave, onHit: Callbacks that fire when a compatible DragDropContainer passes over. onHit is when a compatible container is dropped on the target. These are passed an event containing...

{
    dragData: [whatever you put in the dragData property for the DragDropContainer]
    dragElem: [reference to the DOM element being dragged]
    sourceElem: [reference to the DragDropContainer DOM element]
    target: [reference to the DropContainer DOM element]
}

Wrapper components for dragging an element and dropping it on a target.

• Works on mouse and touch devices.

• Can set it up to drag the element itself or drag a "ghost" node that represents the element.

• Use property targetKey to to identify compatible drag elements and targets.

• Can specify drag handle(s) (if desired) with property dragHandleClassName.

• Can tell the element to return-to-base after dragging, or to stay where you put it.

• Can constrain dragging to one dimension, horizontal or vertical.

• Includes callback properties for onStartDrag, onDragging, onEndDrag, and onDropped.

• Data from the target element is included with the onDropped event triggered in the DragDropContainer.

Demo

Live demo: peterh32.github.io/react-drag-drop-container

To build the demo locally, run:

npm install
npm run launch

This should open the demo in a browser window on localhost:8080.

This error means you're already running something on port 8080:

events.js:160
      throw er; // Unhandled 'error' event

Installation

Install it in your project using npm:

npm install react-drag-drop-container --save

Usage

Set up Draggable Element

Wrap your element in a DragDropContainer:

import { DragDropContainer } from 'react-drag-drop-container';

<DragDropContainer>
    <span>Example</span>
</DragDropContainer>

The element should now be draggable.

Set up for dragging to a target

Add the data you want to send to the target when you drop the element on it:

<DragDropContainer dragData={{label: 'Example', id: 123}}>
	<span>Example</span>
</DragDropContainer>

Specify targetKey. This determines what dropTargets will accept your drag:

<DragDropContainer dragData={{label: 'Example', id: 123}} targetKey="foo">
	<span>Example</span>
</DragDropContainer>

Set up Target(s)

Wrap an element in a DropTarget, giving it the same targetKey as your draggable:

  import { DropTarget } from 'react-drag-drop-container';

  <DropTarget targetKey="foo">
      [some element or text]
  </DropTarget>

In DropTarget's parent, add handlers for the enter, leave, and drop events. For example:

  highlight(ev){
    this.setState({'highlighted': true})
  }

  unHighlight(ev){
 	this.setState({'highlighted': false})
  }
  
  dropped(ev){
    ... do something with event data ...
  }

Wire them up to DropTarget. In this example we are passing the "highlighted" state to the child element, which we assume toggles some highlighted style.

  <DropTarget targetKey="foo" onDragEnter={this.highlight} onDragLeave={this.unHighlight} onHit={this.dropped}>
    <ChildElement highlighted=this.state.highlighted />
  </DropTarget>

DragDropContainer Properties

dragData

Data about the dragged item that you want to pass to the target. Default is empty object.

targetKey

Optional string to specify which DropTargets will accept which DragDropContainers.

dragHandleClassName

Class name for drag handle(s). Optional. If omitted, the whole thing is grabbable.

Tip: If you are using drag handles on an element that contains an image, use <img draggable="false"... to prevent the browser from letting users drag the image itself, which can be confusing.

customDragElement

If a DOM node is provided, we'll drag it instead of the actual object (which will remain in place).

Example:

let elem = <div class="drag_elem">Drag Me</div>;

<DragDropContainer customDragElement={elem}>

noDragging

If true, dragging is turned off.

returnToBase

If true, then dragged item goes back to where you put it when you drop.

xOnly, yOnly

If true, then dragging is constrained to the x- or y direction, respectively.

zIndex

The z-index for the dragged item defaults to 1000 (so that it floats over the target). If that doesn't work for you, change it here.

Callbacks

All optional; specify in props.

onDragStart(dragData)

Runs when you start dragging. dragData is whatever you passed in with the dragData property.

onDrag(dragData, currentTarget, x, y)

Runs as you drag. currentTarget is the DOM element you're currently dragging over; x and y are the current position.

onDragEnd(dragData, currentTarget, x, y)

When you drop.

onDrop(dropData, dropTarget)

Triggered after a drop onto a compatible DropTarget. dropTarget is the DOM element of the DropTarget you dropped on, and dropData is an optional property of DropTarget.

DropTarget Properties

targetKey

Optional string to specify which DragDropContainers this target will accept.

dropData

Data to be provided to the DragDropContainer when it is dropped on the target.

Callbacks

All optional; specify in props.

onDragEnter(e), onDragLeave(e), onHit(e)

The event e contains

{
    dragData: [whatever you put in the dragData property for DragDropContainer]
    dragElem: [reference to the DOM element being dragged]
    sourceElem: [reference to the DragDropContainer DOM element]
}

The sourceElem_ and dragElem properties point to the same object unless you set dragGhost (see below), in which case dragElem is the ghost, and sourceElem is the DragDropContainer.

Example: make the target "consume" the draggable

Use event.sourceElem to hide or delete the source element after a successful drop.

  dropped(ev){
      ev.sourceElem.style.visibility = 'hidden';
  }

Development

/src    Source code for components
/demo   Source code for demo
/lib/bundle.js  Transpiled output
/public   Demo files, compiled

License

NOT LICENSED

Copyright (c) 2017.