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Beautiful, accessible drag and drop for lists with React.js

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react-beautiful-dnd

Beautiful, accessible drag and drop for lists with React.js

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example

Examples 🎉

See how beautiful it is for yourself!

Viewing on a desktop

All the examples!

Viewing on a mobile or tablet

We provide different links for touch devices as currently storybook does not have a good mobile menu experience more information

Upgrading from 3.x to 4.x

You can find an upgrade guide in our release notes.

Core characteristics

  • Beautiful, natural movement of items
  • Clean and powerful api which is simple to get started with
  • Plays extremely well with standard browser interactions
  • Unopinionated styling
  • No creation of additional wrapper dom nodes - flexbox and focus management friendly!

Currently supported feature set

  • Vertical lists ↕
  • Horizontal lists ↔
  • Movement between lists (▤ ↔ ▤)
  • Mouse 🐭, keyboard 🎹 and touch 👉📱 (mobile, tablet and so on) support
  • Conditional dragging and dropping
  • Multiple independent lists on the one page
  • Independent nested lists - a list can be a child of another list, but you cannot drag items from the parent list into a child list
  • Flexible item sizes - the draggable items can have different heights (vertical) or widths (horizontal))
  • Custom drag handle - you can drag a whole item by just a part of it
  • A droppable list can be a scroll container (without a scrollable parent) or be the child of a scroll container (that also does not have a scrollable parent)
  • Server side rendering compatible
  • Plays well with nested interactive elements by default

Lots more coming soon

You can check out all the features that will be landing soon on our issue page.

Not for everyone

There are a lot of libraries out there that allow for drag and drop interactions within React. Most notable of these is the amazing react-dnd. It does an incredible job at providing a great set of drag and drop primitives which work especially well with the wildly inconsistent html5 drag and drop feature. react-beautiful-dnd is a higher level abstraction specifically built for vertical and horizontal lists. Within that subset of functionality react-beautiful-dnd offers a powerful, natural and beautiful drag and drop experience. However, it does not provide the breadth of functionality offered by react-dnd. So this library might not be for you depending on what your use case is.

Basic usage example

This is a simple reorderable list. You can play with it on webpackbin

basic example

import React, { Component } from 'react';
import ReactDOM from 'react-dom';
import { DragDropContext, Droppable, Draggable } from 'react-beautiful-dnd';

// fake data generator
const getItems = count =>
  Array.from({ length: count }, (v, k) => k).map(k => ({
    id: `item-${k}`,
    content: `item ${k}`,
  }));

// a little function to help us with reordering the result
const reorder = (list, startIndex, endIndex) => {
  const result = Array.from(list);
  const [removed] = result.splice(startIndex, 1);
  result.splice(endIndex, 0, removed);

  return result;
};

// using some little inline style helpers to make the app look okay
const grid = 8;
const getItemStyle = (isDragging, draggableStyle) => ({
  // some basic styles to make the items look a bit nicer
  userSelect: 'none',
  padding: grid * 2,
  margin: `0 0 ${grid}px 0`,

  // change background colour if dragging
  background: isDragging ? 'lightgreen' : 'grey',

  // styles we need to apply on draggables
  ...draggableStyle,
});
const getListStyle = isDraggingOver => ({
  background: isDraggingOver ? 'lightblue' : 'lightgrey',
  padding: grid,
  width: 250,
});

class App extends Component {
  constructor(props) {
    super(props);
    this.state = {
      items: getItems(10),
    };
    this.onDragEnd = this.onDragEnd.bind(this);
  }

  onDragEnd(result) {
    // dropped outside the list
    if (!result.destination) {
      return;
    }

    const items = reorder(
      this.state.items,
      result.source.index,
      result.destination.index
    );

    this.setState({
      items,
    });
  }

  // Normally you would want to split things out into separate components.
  // But in this example everything is just done in one place for simplicity
  render() {
    return (
      <DragDropContext onDragEnd={this.onDragEnd}>
        <Droppable droppableId="droppable">
          {(provided, snapshot) => (
            <div
              ref={provided.innerRef}
              style={getListStyle(snapshot.isDraggingOver)}
            >
              {this.state.items.map((item, index) => (
                <Draggable key={item.id} draggableId={item.id} index={index}>
                  {(provided, snapshot) => (
                    <div>
                      <div
                        ref={provided.innerRef}
                        {...provided.draggableProps}
                        {...provided.dragHandleProps}
                        style={getItemStyle(
                          snapshot.isDragging,
                          provided.draggableProps.style,
                        )}
                      >
                        {item.content}
                      </div>
                      {provided.placeholder}
                    </div>
                  )}
                </Draggable>
              ))}
              {provided.placeholder}
            </div>
          )}
        </Droppable>
      </DragDropContext>
    );
  }
}

// Put the thing into the DOM!
ReactDOM.render(<App />, document.getElementById('app'));

Driving philosophy: physicality

The core design idea of react-beautiful-dnd is physicality: we want users to feel like they are moving physical objects around

Application 1: no instant movement

It is a fairly standard drag and drop pattern for things to disappear and reappear in response to the users drag. For a more natural drag we animate the movement of items as they need to move out of the way while dragging to more clearly show a drags effect. We also animate the drop of an item so that it animates into its new home position. At no point is an item instantly moved anywhere — regardless of whether it is dragging or not.

Application 2: knowing when to move

It is quite common for drag and drop interactions to be based on the position that user started the drag from.

In react-beautiful-dnd a dragging items impact is based on its centre of gravity — regardless of where a user grabs an item from. A dragging items impact follows similar rules to a set of scales ⚖️. Here are some rules that are followed to allow for a natural drag experience even with items of flexible height:

  • A list is dragged over when the centre position of a dragging item goes over one of the boundaries of the list
  • A resting drag item will move out of the way of a dragging item when the centre position of the dragging item goes over the edge of the resting item. Put another way: once the centre position of an item (A) goes over the edge of another item (B), B moves out of the way.

Application 3: no drop shadows

Drop shadows are useful in an environment where items and their destinations snap around. However, with react-beautiful-dnd it should be obvious where things will be dropping based on the movement of items. This might be changed in the future - but the experiment is to see how far we can get without any of these affordances.

Application 4: maximise interactivity

react-beautiful-dnd works really hard to avoid as many periods of non-interactivity as possible. The user should feel like they are in control of the interface and not waiting for an animation to finish before they can continue to interact with the interface. However, there is a balance that needs to be made between correctness and power in order to make everybody's lives more sane. Here are the only situations where some things are not interactive:

  1. From when a user cancels a drag to when the drop animation completes. On cancel there are lots of things moving back to where they should be. If you grab an item in a location that is not its true home then the following drag will be incorrect.
  2. Starting a drag on an item that is animating its own drop. For simplicity this is the case - it is actually quite hard to grab something while it is animating home. It could be coded around - but it seems like an edge case that would add a lot of complexity.

Keep in mind that these periods of inactivity may not always exist.

Application 5: no drag axis locking

For now, the library does not support drag axis locking (aka drag rails). This is where the user is restricted to only dragging along one axis. The current thinking is this breaks the physical metaphor we are going for and sends a message to the user that they are interacting with a piece of software rather than moving physical objects around. It is possible to ensure that a user can only drop in a single list by using props type and isDropDisabled. You can also do some visual treatment to the list onDragStart to show the user that this is the only place they can interact with.

Application 6: natural cross list movement

Rather than using an index based approach for keyboard movement between lists, react-beautiful-dnd performs cross list movement based on inertia, gravity and collisions. You can find out more about how this works by reading the blog "Natural keyboard movement between lists".

example

Carefully designed animations

With things moving a lot it would be easy for the user to become distracted by the animations or for them to get in the way. We have tweaked the various animations to ensure the right balance of guidance, performance and interactivity.

Dropping

When you drop a dragging item its movement is based on physics (thanks react-motion). This results in the drop feeling more weighted and physical.

Moving out of the way

Items that are moving out of the way of a dragging item do so with a CSS transition rather than physics. This is to maximise performance by allowing the GPU to handle the movement. The CSS animation curve has been designed to communicate getting out of the way.

How it is composed:

  1. A warm up period to mimic a natural response time
  2. A small phase to quickly move out of the way
  3. A long tail so that people can read any text that is being animated in the second half of the animation

animation curve

animation curve used when moving out of the way

Caring about the interaction details

Focus management

react-beautiful-dnd does not create any wrapper elements. This means that it will not impact the usual tab flow of a document. For example, if you are wrapping an anchor tag then the user will tab to the anchor directly and not an element surrounding the anchor. Whatever element you wrap will be given a tab-index to ensure that users can tab to the element to perform keyboard dragging.

Accessibility

Traditionally drag and drop interactions have been exclusively a mouse or touch interaction. This library ships with support for drag and drop interactions using only a keyboard. This enables power users to drive their experience entirely from the keyboard. As well as opening up these experiences to users who would have been excluded previously.

In addition to supporting keyboard, we have also audited how the keyboard shortcuts interact with standard browser keyboard interactions. When the user is not dragging they can use their keyboard as they normally would. While dragging we override and disable certain browser shortcuts (such as tab) to ensure a fluid experience for the user.

Mouse dragging

Sloppy clicks and click blocking 🐱🎁

When a user presses the mouse down on an element, we cannot determine if the user was clicking or dragging. Also, sometimes when a user clicks they can move the cursor slightly — a sloppy click. So we only start a drag once the user has moved beyond a certain distance with the mouse down (the drag threshold) — more than they would if they were just making a sloppy click. If the drag threshold is not exceeded then the user interaction behaves just like a regular click. If the drag threshold is exceeded then the interaction will be classified as a drag and the standard click action will not occur.

This allows consumers to wrap interactive elements such as an anchor and have it be both a standard anchor as well as a draggable item in a natural way.

(🐱🎁 is a schrodinger's cat joke)

Keyboard shortcuts: mouse dragging

When a drag is not occurring react-beautiful-dnd does not impact any of the standard keyboard interactions (it has no listeners bound).

When a drag is occurring with a mouse the user is able to execute the following keyboard shortcuts:

  • escape esc - cancel the drag

During a mouse drag the following standard keyboard events are blocked to prevent a bad experience:

  • tab tab ↹ - blocking tabbing
  • enter - blocking submission

Other than these explicitly blocked keyboard events all standard keyboard events should work as expected.

Keyboard dragging

react-beautiful-dnd supports dragging with only a keyboard

Keyboard shortcuts: keyboard dragging

When a drag is not occurring, key the user will be able to navigation through the Draggable's on a page using the standard tab tab ↹ key to move forward through the tabbable elements and (shift + tab) (shift + )tab ↹) to move backwards. We achieve this by adding a tab-index to the Draggable. When a Draggable has focus the spacebar space will lift a Draggable. This will start the drag.

Once a drag is started the following keyboard shortcuts can be used:

  • spacebar space - drop the Draggable
  • escape esc - cancel the drag

The following commands are also available but they depend on the type of Droppable that the Draggable is currently in:

Within a vertical list

  • Up arrow - move a Draggable upwards in a Droppable
  • Down arrow - move a Draggable downwards in a Droppable
  • Right arrow - move a Draggable to a Droppable to the right of the current Droppable (move to new list)
  • Left arrow - move a Draggable to a Droppable to the left of the current Droppable (move to new list)

Within a horizontal list

  • Up arrow - move a Draggable to a Droppable to above the current Droppable (move to new list)
  • Down arrow - move a Draggable to a Droppable to below the current Droppable (move to new list)
  • Right arrow - move a Draggable to the right in the current Droppable
  • Left arrow - move a Draggable to the left in the current Droppable

During a drag the following standard keyboard events are blocked to prevent a bad experience:

  • tab tab ↹ - blocking tabbing
  • enter - blocking submission

Limitations of keyboard dragging

There is current limitation of keyboard dragging: the drag will cancel if the user scrolls the window. This could be worked around but for now it is the simplest initial approach.

Touch dragging

react-beautiful-dnd supports dragging on touch devices such as mobiles and tablets.

Mobile landscape

Recorded on iPhone 6s

Understanding intention: tap, force press, scroll and drag

When a user presses their finger (or other input) on a Draggable we are not sure if they where intending to tap, force press, scroll the container or drag. As much as possible react-beautiful-dnd aims to ensure that a users default interaction experience remains unaffected.

Starting a drag: long press

A user can start a drag by holding their finger 👇 on an element for a small period of time 🕑 (long press)

Tap support

If the user lifts their finger before the timer is finished then we release the event to the browser for it to determine whether to perform the standard tap / click action. This allows you to have a Draggable that is both clickable such as a anchor as well as draggable. If the item was dragged then we block the tap action from occurring.

Native scrolling support

If we detect a touchmove before the long press timer expires we cancel the pending drag and allow the user to scroll normally. This means that the user needs to be fairly intentional and precise with their grabbing. Once the first touchmove occurs we have to either opt in our out of native scrolling.

  • If the long press timer has not expired: allow native scrolling and prevent dragging
  • If the long press timer has expired: a drag has started and we prevent native scrolling

Force press support

Safari only

If the user force presses on the element before they have moved the element (even if a drag has already started) then the drag is cancelled and the standard force press action occurs. For an anchor this is a website preview.

Vibration

This is merely an idea - it is up to you to add this if you want this behavior.

If you like you could also trigger a vibration event when the user picks up a Draggable. This can provide tactile feedback that the user is doing something. It currently is only supported in Chrome on Android.

class App extends React.Component {
  onDragStart = () => {
    // good times
    if (window.navigator.vibrate) {
      window.navigator.vibrate(100);
    }
  };
  /*...*/
}

Preset styles

We apply a number of non-visible styles to facilitate the dragging experience. We do this using combination of styling targets and techniques. It is a goal of the library to provide unopinioned styling. However, we do apply some reasonable cursor styling on drag handles by default. This is designed to make the library work as simply as possible out of the box. If you want to use your own cursors you are more than welcome to. All you need to do is override our cursor style rules by using a rule with higher specificity.

Here are the styles that are applied at various points in the drag lifecycle:

In every phase

Always: drag handle

Styles applied to: drag handle element using the data-react-beautiful-dnd-drag-handle attribute.

A long press on anchors usually pops a content menu that has options for the link such as 'Open in new tab'. Because long press is used to start a drag we need to opt out of this behavior

-webkit-touch-callout: none;

Webkit based browsers add a grey overlay to anchors when they are active. We remove this tap overlay as it is confusing for users. more information.

-webkit-tap-highlight-color: rgba(0,0,0,0);

Avoid the pull to refresh action and delayed anchor focus on Android Chrome

touch-action: manipulation;

Phase: resting

(Phase: resting): drag handle

Styles applied to: drag handle element using the data-react-beautiful-dnd-drag-handle attribute.

Adding a cursor style to let the user know this element is draggable. You are welcome to override this.

cursor: grab;

Phase: dragging

(Phase: dragging): drag handle element

Styles applied using the data-react-beautiful-dnd-drag-handle attribute

An optimisation to avoid processing pointer-events while dragging. Also used to allow scrolling through a drag handle with a track pad or mouse wheel.

point-events: none;

(Phase: dragging): Draggable element

Styles applied using the data-react-beautiful-dnd-draggable attribute

This is what we use to control Draggables that need to move out of the way of a dragging Draggable.

transition: ${string};

Styles applied using inline styles

This is described by the type DraggableStyle.

(Phase: dragging): body element

We apply a cursor while dragging to give user feedback that a drag is occurring. You are welcome to override this. A good point to do this is the onDragStart event.

cursor: grabbing;

To prevent the user selecting text as they drag apply this style

user-select: none;

Phase: dropping

(Phase: dropping): drag handle element

Styles applied using the data-react-beautiful-dnd-drag-handle attribute

We apply the grab cursor to all drag handles except the drag handle for the dropping Draggable. At this point the user is able to drag other Draggable's if they like.

cursor: grab;

(Phase: dropping): draggable

Same as dragging phase

Phase: user cancel

When a user explicitly cancels a drag

This is the same as Phase: dropping. However we do not apply a cursor: grab to the drag handle. During a user initiated cancel we do not allow the dragging of other items until the drop animation is complete.

Preset styles are vendor prefixed

All styles applied are vendor prefixed correctly to meet the requirements of our supported browser matrix. This is done by hand to avoid adding to react-beautiful-dnd's size by including a css-in-js library

Installation

Package manager

# yarn
yarn add react-beautiful-dnd

# npm
npm install react-beautiful-dnd --save

Distribution bundle

A universal module definition bundle is published on npm under the /dist folder for consumption . We publish the following files:

  • dist/react-beautiful-dnd.js
  • dist/react-beautiful-dnd.min.js (minified bundle)

These bundles list react as an external which needs to be provided. This is done to reduce the size of the bundle and prevent consumers from loading react multiple times. You can provide react through your module system or simply by having react on the window.

You can use the UMD to run react-beautiful-dnd directly in the browser.

<!-- peer dependency -->
<script src="https://unpkg.com/[email protected]/dist/react.js"></script>
<!-- lib (change x.x.x for the version you would like) -->
<script src="https://unpkg.com/[email protected]/dist/react-beautiful-dnd.js"></script>
<!-- needed to mount your react app -->
<script src="https://unpkg.com/[email protected]/dist/react-dom.js"></script>

<script>
  const React = window.React;
  const ReactDOM = window.ReactDOM;
  const { DragDropContext, Draggable, Droppable } = window.ReactBeautifulDnd;

  class App extends React.Component {
    //...
  }

  // You can use JSX if your environment supports it
  ReactDOM.render(React.createElement(App), document.getElementById('app'));
</script>

There is also an example codepen you can use to play with this installation method.

You can consume react-beautiful-dnd from within ClojureScript using CLJSJS!

API

Okay, into the fun stuff - so how do you use the library?

DragDropContext

In order to use drag and drop, you need to have the part of your React tree that you want to be able to use drag and drop in wrapped in a DragDropContext. It is advised to just wrap your entire application in a DragDropContext. Having nested DragDropContext's is not supported. You will be able to achieve your desired conditional dragging and dropping using the props of Droppable and Draggable. You can think of DragDropContext as having a similar purpose to the react-redux Provider component

Props

type Hooks = {|
  onDragStart?: (initial: DragStart) => void,
  onDragEnd: (result: DropResult) => void,
|}

type Props = {|
  ...Hooks,
  children?: ReactElement,
|}

Basic usage

import { DragDropContext } from 'react-beautiful-dnd';

class App extends React.Component {
  onDragStart = () => {
    /*...*/
  };
  onDragEnd = () => {
    /*...*/
  };

  render() {
    return (
      <DragDropContext
        onDragStart={this.onDragStart}
        onDragEnd={this.onDragEnd}
      >
        <div>Hello world</div>
      </DragDropContext>
    );
  }
}

Hooks

These are top level application events that you can use to perform your own state updates.

onDragStart (optional)

This function will get notified when a drag starts. You are provided with the following details:

initial: DragStart

  • initial.draggableId: the id of the Draggable that is now dragging
  • initial.type: the type of the Draggable that is now dragging
  • initial.source: the location (droppableId and index) of where the dragging item has started within a Droppable.

This function is optional and therefore does not need to be provided. It is highly recommended that you use this function to block updates to all Draggable and Droppable components during a drag. (See *Best practices for hooks *)

onDragStart type information

onDragStart?: (initial: DragStart) => void

// supporting types
type DragStart = {|
  draggableId: DraggableId,
  type: TypeId,
  source: DraggableLocation,
|}

type DraggableLocation = {|
  droppableId: DroppableId,
  // the position of the draggable within a droppable
  index: number
|};
type Id = string;
type DraggableId = Id;
type DroppableId = Id;
type TypeId = Id;

onDragEnd (required)

This function is extremely important and has an critical role to play in the application lifecycle. This function must result in the synchronous reordering of a list of Draggables

It is provided with all the information about a drag:

result: DropResult

  • result.draggableId: the id of the Draggable that was dragging.
  • result.type: the type of the Draggable that was dragging.
  • result.source: the location where the Draggable started.
  • result.destination: the location where the Draggable finished. The destination will be null if the user dropped into no position (such as outside any list) or if they dropped the Draggable back into the same position in which it started.

Synchronous reordering

Because this library does not control your state, it is up to you to synchronously reorder your lists based on the result.

Here is what you need to do:

  • if the destination is null: all done!
  • if source.droppableId equals destination.droppableId you need to remove the item from your list and insert it at the correct position.
  • if source.droppableId does not equal destination.droppableId, then you need to remove the Draggable from the source.droppableId list and add it into the correct position of the destination.droppableId list.

Persisting a reorder

If you need to persist a reorder to a remote data store - update the list synchronously on the client and fire off a request in the background to persist the change. If the remote save fails it is up to you how to communicate that to the user and update, or not update, the list.

onDragEnd type information

onDragEnd: (result: DropResult) => void

// supporting types
type DropResult = {|
  draggableId: DraggableId,
  type: TypeId,
  source: DraggableLocation,
  // may not have any destination (drag to nowhere)
  destination: ?DraggableLocation
|}

type Id = string;
type DroppableId = Id;
type DraggableId = Id;
type TypeId = Id;
type DraggableLocation = {|
  droppableId: DroppableId,
  // the position of the droppable within a droppable
  index: number
|};

Best practices for hooks

Block updates during a drag

It is highly recommended that while a user is dragging that you block any state updates that might impact the amount of Draggables and Droppables, or their dimensions. Please listen to onDragStart and block updates to the Draggables and Droppables until you receive at onDragEnd.

When the user starts dragging we take a snapshot of all of the dimensions of the applicable Draggable and Droppable nodes. If these change during a drag we will not know about it.

Here are a few poor user experiences that can occur if you change things during a drag:

  • If you increase the amount of nodes, then the library will not know about them and they will not be moved when the user would expect them to be.
  • If you decrease the amount of nodes, then there might be gaps and unexpected movements in your lists.
  • If you change the dimensions of any node, then it can cause the changed node as well as others to move at incorrect times.
  • If you remove the node that the user is dragging, then the drag will instantly end
  • If you change the dimension of the dragging node, then other things will not move out of the way at the correct time.

Force focus after a transition between lists

When an item is moved from one list to a different list, it loses browser focus if it had it. This is because React creates a new node in this situation. It will not lose focus if transitioned within the same list. The dragging item will always have had browser focus if it is dragging with a keyboard. It is highly recommended that you give the item (which is now in a different list) focus again. You can see an example of how to do this in our stories. Here is an example of how you could do it:

  • onDragEnd: move the item into the new list and record the id of the item that has moved
  • When rendering the reordered list, pass down a prop which will tell the newly moved item to obtain focus
  • In the componentDidMount lifecycle call back check if the item needs to gain focus based on its props (such as an autoFocus prop)
  • If focus is required - call .focus on the node. You can obtain the node by using ReactDOM.findDOMNode or monkey patching the provided.innerRef callback.

onDragStart and onDragEnd pairing

We try very hard to ensure that each onDragStart event is paired with a single onDragEnd event. However, there maybe a rogue situation where this is not the case. If that occurs - it is a bug. Currently there is no mechanism to tell the library to cancel a current drag externally.

Droppable

Droppable components can be dropped on by a Draggable. They also contain Draggables. A Draggable must be contained within a Droppable.

import { Droppable } from 'react-beautiful-dnd';

<Droppable droppableId="droppable-1" type="PERSON">
  {(provided, snapshot) => (
    <div
      ref={provided.innerRef}
      style={{ backgroundColor: snapshot.isDraggingOver ? 'blue' : 'grey' }}
    >
      <h2>I am a droppable!</h2>
      {provided.placeholder}
    </div>
  )}
</Droppable>;

Droppable props

  • droppableId: A required DroppableId(string) that uniquely identifies the droppable for the application. Please do not change this prop - especially during a drag.
  • type: An optional TypeId(string) that can be used to simply accept a class of Draggable. For example, if you use the type PERSON then it will only allow Draggables of type PERSON to be dropped on itself. Draggables of type TASK would not be able to be dropped on a Droppable with type PERSON. If no type is provided, it will be set to 'DEFAULT'. Currently the type of the Draggables within a Droppable must be the same. This restriction might be loosened in the future if there is a valid use case.
  • isDropDisabled: An optional flag to control whether or not dropping is currently allowed on the Droppable. You can use this to implement your own conditional dropping logic. It will default to false.
  • direction: The direction in which items flow in this droppable. Options are vertical (default) and horizontal.
  • ignoreContainerClipping: When a Droppable is inside a scrollable container its area is constrained so that you can only drop on the part of the Droppable that you can see. Setting this prop opts out of this behavior, allowing you to drop anywhere on a Droppable even if it's visually hidden by a scrollable parent. The default behavior is suitable for most cases so odds are you'll never need to use this prop, but it can be useful if you've got very long Draggables inside a short scroll container. Keep in mind that it might cause some unexpected behavior if you have multiple Droppables inside scroll containers on the same page.

Children function

The React children of a Droppable must be a function that returns a ReactElement.

<Droppable droppableId="droppable-1">
  {(provided, snapshot) => ({
    /*...*/
  })}
</Droppable>;

The function is provided with two arguments:

1. provided: (DroppableProvided)**

type DroppableProvided = {|
  innerRef: (?HTMLElement) => void,
  placeholder: ?ReactElement,
|}
  • provided.innerRef: In order for the droppable to function correctly, you must bind the provided.innerRef to the highest possible DOM node in the ReactElement. We do this in order to avoid needing to use ReactDOM to look up your DOM node.

  • provided.placeholder: This is used to create space in the Droppable as needed during a drag. This space is needed when a user is dragging over a list that is not the home list. Please be sure to put the placeholder inside of the component for which you have provided the ref. We need to increase the side of the Droppable itself. This is different from Draggable where the placeholder needs to be a sibling to the draggable node.

<Droppable droppableId="droppable-1">
  {(provided, snapshot) => (
    <div ref={provided.innerRef}>
      Good to go

      {provided.placeholder}
    </div>
  )}
</Droppable>;

2. snapshot: (DroppableStateSnapshot)**

type DroppableStateSnapshot = {|
  isDraggingOver: boolean,
|};

The children function is also provided with a small amount of state relating to the current drag state. This can be optionally used to enhance your component. A common use case is changing the appearance of a Droppable while it is being dragged over.

<Droppable droppableId="droppable-1">
  {(provided, snapshot) => (
    <div
      ref={provided.innerRef}
      style={{ backgroundColor: snapshot.isDraggingOver ? 'blue' : 'grey' }}
    >
      I am a droppable!

      {provided.placeholder}
    </div>
  )}
</Droppable>;

Conditionally dropping

  • Droppables can only be dropped on by Draggables who share the same type. This is a simple way of allowing conditional dropping. If you do not provide a type for the Droppable, then it will only accept Draggables which also have the default type. Draggables and Droppables both will have their types set to 'DEFAULT' when none is provided. There is currently no way to set multiple types, or a type wildcard that will accept Draggables of multiple any types. This could be added if there is a valid use case.
  • Using the isDropDisabled prop you can conditionally allow dropping. This allows you to do arbitrarily complex conditional transitions. This will only be considered if the type of the Droppable matches the type of the currently dragging Draggable.
  • You can disable dropping on a Droppable altogether by always setting isDropDisabled to false. You can do this to create a list that is never able to be dropped on, but contains Draggables.
  • Technically you do not need to use type and do all of your conditional drop logic with the isDropDisabled function. The type parameter is a convenient shortcut for a common use case.

Scroll containers

This library supports dragging within scroll containers (DOM elements that have overflow: auto; or overflow: scroll;). The only supported use cases are:

  1. The Droppable can itself be a scroll container with no scrollable parents
  2. The Droppable has one scrollable parent

Empty Droppables

It is recommended that you put a min-height on a vertical Droppable or a min-width on a horizontal Droppable. Otherwise when the Droppable is empty there may not be enough of a target for Draggable being dragged with touch or mouse inputs to be over the Droppable.

Recommended Droppable performance optimisation

When a user drags over, or stops dragging over, a Droppable we re-render the Droppable with an updated DroppableStateSnapshot > isDraggingOver value. This is useful for styling the Droppable. However, by default this will cause a render of all of the children of the Droppable - which might be 100's of Draggables! This can result in a noticeable frame rate drop. To avoid this problem we recommend that you create a component that is the child of a Droppable who's responsibility it is to avoid rendering children if it is not required.

Here is an example of how you could do this:

import React, { Component } from 'react';

class Student extends Component<{ student: Person }> {
  render() {
    // Renders out a draggable student
  }
}

class InnerList extends Component<{ students: Person[] }> {
  // do not re-render if the students list has not changed
  shouldComponentUpdate(nextProps: Props) {
    if(this.props.students === nextProps.students) {
      return false;
    }
    return true;
  }
  // You could also not do your own shouldComponentUpdate check and just
  // extend from React.PureComponent

  render() {
    return this.props.students.map((student: Person) => (
      <Student student={student} />
    ))
  }
}

class Students extends Component {
  render() {
    return (
      <Droppable droppableId="list">
        {(provided: DroppableProvided, snapshot: DroppableStateSnapshot) => (
          <div
            ref={provided.innerRef}
            style={{ backgroundColor: provided.isDragging ? 'green' : 'lightblue' }}
          >
            <InnerList students={this.props.students} />
            {provided.placeholder}
          </div>
        )}
      </Droppable>
    )
  }
}

By using the approach you are able to make style changes to a Droppable when it is being dragged over, but you avoid re-rendering all of the children unnecessarily. Keep in mind that if you are using React.PureComponent that your component will not respond to changes in the context.

Unfortunately we are unable to apply this optimisation for you. It is a byproduct of using the function-as-child pattern.

Auto scrolling is not provided (yet!)

Currently auto scrolling of scroll containers is not part of this library. Auto scrolling is where the container automatically scrolls to make room for the dragging item as you drag near the edge of a scroll container. You are welcome to build your own auto scrolling list, or if you would you really like it as part of this library we could provide a auto scrolling Droppable.

Users will be able to scroll a scroll container while dragging by using their trackpad or mouse wheel.

Keyboard dragging limitation

Getting keyboard dragging to work with scroll containers is quite difficult. Currently there is a limitation: you cannot drag with a keyboard beyond the visible edge of a scroll container. This limitation could be removed if we introduced auto scrolling. Scrolling a container with a mouse during a keyboard drag will cancel the drag.

Draggable

Draggable components can be dragged around and dropped onto Droppables. A Draggable must always be contained within a Droppable. It is possible to reorder a Draggable within its home Droppable or move to another Droppable. It is possible because a Droppable is free to control what it allows to be dropped on it.

import { Draggable } from 'react-beautiful-dnd';

<Draggable draggableId="draggable-1" type="PERSON" index={0}>
  {(provided, snapshot) => (
    <div>
      <div
        ref={provided.innerRef}
        {...provided.draggableProps}
        {...provided.dragHandleProps}
      >
        <h4>My draggable</h4>
      </div>
      {provided.placeholder}
    </div>
  )}
</Draggable>;

Note: when the library moves to React 16 this will be cleaned up a little bit as we will be able to return the placeholder as a sibling to your child function without you needing to create a wrapping element

Draggable Props

  • draggableId: A required DraggableId(string) that uniquely identifies the Draggable for the application. Please do not change this prop - especially during a drag.
  • type: An optional type (TypeId(string)) of the Draggable. This is used to control what Droppables the Draggable is permitted to drop on. Draggables can only drop on Droppables that share the same type. If no type is provided, then it will be set to 'DEFAULT'. Currently the type of a Draggable must be the same as its container Droppable. This restriction might be loosened in the future if there is a valid use case.
  • isDragDisabled: An optional flag to control whether or not the Draggable is permitted to drag. You can use this to implement your own conditional drag logic. It will default to false.
  • disableInteractiveElementBlocking: An optional flag to opt out of blocking a drag from interactive elements. For more information refer to the section Interactive child elements within a Draggable

Children function

The React children of a Draggable must be a function that returns a ReactElement.

<Draggable draggableId="draggable-1" index={0}>
  {(provided, snapshot) => (
    <div>
      <div
        ref={provided.innerRef}
        {...provided.draggableProps}
        {...provided.dragHandleProps}
      >
        Drag me!
      </div>
      {provided.placeholder}
    </div>
  )}
</Draggable>;

The function is provided with two arguments:

1. provided: (DraggableProvided)**

type DraggableProvided = {|
  innerRef: (HTMLElement) => void,
  draggableProps: ?DraggableProps,
  dragHandleProps: ?DragHandleProps,
  placeholder: ?ReactElement,
|}

Everything within the provided object must be applied for the Draggable to function correctly.

  • provided.innerRef (innerRef: (HTMLElement) => void): In order for the Droppable to function correctly, you must bind the innerRef function to the ReactElement that you want to be considered the Draggable node. We do this in order to avoid needing to use ReactDOM to look up your DOM node.
<Draggable draggableId="draggable-1" index={0}>
  {(provided, snapshot) => <div ref={provided.innerRef}>Drag me!</div>}
</Draggable>;

Type information

innerRef: (HTMLElement) => void
  • provided.draggableProps (?DraggableProps): This is an Object that contains a data attribute and an inline style. This Object needs to be applied to the same node that you apply provided.innerRef to. This controls the movement of the draggable when it is dragging and not dragging. You are welcome to add your own styles to DraggableProps > style – but please do not remove or replace any of the properties.

Type information

// Props that can be spread onto the element directly
export type DraggableProps = {|
  // inline style
  style: ?DraggableStyle,
  // used for shared global styles
  'data-react-beautiful-dnd-draggable': string,
|}
<Draggable draggableId="draggable-1" index={0}>
  {(provided, snapshot) => (
    <div>
      <div ref={provided.innerRef} {...provided.draggableProps}>
        Drag me!
      </div>
    </div>
  )}
</Draggable>;

Positioning ownership

It is a contract of this library that it owns the positioning logic of the dragging element. This includes properties such as top, right, bottom, left and transform. The library may change how it positions things and which properties it uses without performing a major version bump. It is also recommended that you do not apply your own transition property to the dragging element.

Warning: position: fixed

react-beautiful-dnd uses position: fixed to position the dragging element. This is quite robust and allows for you to have position: relative | absolute | fixed parents. However, unfortunately position:fixed is impacted by transform (such as transform: rotate(10deg);). This means that if you have a transform: * on one of the parents of a Draggable then the positioning logic will be incorrect while dragging. Lame! For most consumers this will not be an issue.

This will be changing soon as we move to a portal solution where we will be appending the Draggable to the end of the body to avoid any parent transforms. If you really need this feature right now we have created an example where we implement a portal on top of the current api. Please note however, this technique is not officially supported and might break in minor / patch releases.

Extending DraggableProps > style

If you are using inline styles you are welcome to extend the DraggableProps > style object. You are also welcome to apply the DraggableProps > style object using inline styles and use your own styling solution for the component itself - such as styled-components.

If you are overriding inline styles be sure to do it after you spread the provided.draggableProps or the spread will override your inline style.

<Draggable draggable="draggable-1" index={0}>
  {(provided, snapshot) => {
    // extending the DraggableStyle with our own inline styles
    const style = {
      backgroundColor: snapshot.isDragging ? 'blue' : 'white',
      fontSize: 18,
      ...provided.draggableProps.style,
    };
    return (
      <div>
        <div
          ref={provided.innerRef}
          {...provided.draggableProps}
          style={style}
        >
          Drag me!
        </div>
      </div>
    );
  }}
</Draggable>;

Avoid margin collapsing between Draggables

margin collapsing is one of those really hard parts of CSS. For our purposes, if you have one Draggable with a margin-bottom: 10px and the next Draggable has a margin-top: 12px these margins will collapse and the resulting margin will be the greater of the two: 12px. When we do our calculations we are currently not accounting for margin collapsing. If you do want to have a margin on the siblings, wrap them both in a div and apply the margin to the inner div so they are not direct siblings.

Draggables should be visible siblings

It is an assumption that Draggables and visible siblings of one another. There can be other elements in between, but these elements should not take up any additional space. You probably will not do this anyway, but just calling it out to be super clear

// Direct siblings ✅
<Draggable draggableId="draggable-1" index={0}>
  {() => {}}
</Draggable>
<Draggable draggableId="draggable-2" index={1}>
  {() => {}}
</Draggable>

// Not direct siblings, but are visual siblings ✅
<div>
  <Draggable draggableId="draggable-1" index={0}>
    {() => {}}
  </Draggable>
</div>
<div>
  <Draggable draggableId="draggable-2" index={1}>
    {() => {}}
  </Draggable>
</div>

// Spacer elements ❌
<Draggable draggableId="draggable-1" index={0}>
    {() => {}}
</Draggable>
<p>I will break things!</p>
<Draggable draggableId="draggable-2" index={1}>
    {() => {}}
</Draggable>

// Spacing on non sibling wrappers ❌
<div style={{padding: 10}}>
  <Draggable draggableId="draggable-1" index={0}>
    {() => {}}
  </Draggable>
</div>
<div style={{padding: 10}}>
  <Draggable draggableId="draggable-2" index={1}>
    {() => {}}
  </Draggable>
</div>

Type information

type DraggingStyle = {|
  pointerEvents: 'none',
  position: 'fixed',
  width: number,
  height: number,
  pointerEvents: 'none',
  boxSizing: 'border-box',
  top: number,
  left: number,
  margin: 0,
  transition: 'none',
  transform: ?string,
  zIndex: ZIndex,
|}

type NotDraggingStyle = {|
  transition: ?string,
  transition: null | 'none',
|};
  • provided.placeholder (?ReactElement) The Draggable element has position: fixed applied to it while it is dragging. The role of the placeholder is to sit in the place that the Draggable was during a drag. It is needed to stop the Droppable list from collapsing when you drag. It is advised to render it as a sibling to the Draggable node. This is unlike Droppable where the placeholder needs to be within the Droppable node. When the library moves to React 16 the placeholder will be removed from api.
<Draggable draggableId="draggable-1" index={0}>
  {(provided, snapshot) => (
    <div>
      <div ref={provided.innerRef} {...provided.draggableProps}>
        Drag me!
      </div>
      {/* Always render me - I will be null if not required */}
      {provided.placeholder}
    </div>
  )}
</Draggable>;
  • provided.dragHandleProps (?DragHandleProps) every Draggable has a drag handle. This is what is used to drag the whole Draggable. Often this will be the same node as the Draggable, but sometimes it can be a child of the Draggable. DragHandleProps need to be applied to the node that you want to be the drag handle. This is a number of props that need to be applied to the Draggable node. The simplest approach is to spread the props onto the draggable node ({...provided.dragHandleProps}). However, you are also welcome to monkey patch these props if you also need to respond to them. DragHandleProps will be null when isDragDisabled is set to true.

Type information

type DragHandleProps = {|
  onMouseDown: (event: MouseEvent) => void,
  onKeyDown: (event: KeyboardEvent) => void,
  onClick: (event: MouseEvent) => void,
  tabIndex: number,
  'aria-grabbed': boolean,
  draggable: boolean,
  onDragStart: () => void,
  onDrop: () => void,
|};

Example: standard

<Draggable draggableId="draggable-1" index={0}>
  {(provided, snapshot) => (
    <div>
      <div
        ref={provided.innerRef}
        {...provided.draggableProps}
        {...provided.dragHandleProps}
      >
        Drag me!
      </div>
      {provided.placeholder}
    </div>
  )}
</Draggable>;

Example: custom drag handle

Controlling a whole draggable by just a part of it

<Draggable draggableId="draggable-1" index={0}>
  {(provided, snapshot) => (
    <div>
      <div ref={provided.innerRef} {...provided.draggableProps}>
        <h2>Hello there</h2>
        <div {...provided.dragHandleProps}>Drag handle</div>
      </div>
      {provided.placeholder}
    </div>
  )}
</Draggable>;

Monkey patching

You can override some of the dragHandleProps props with your own behavior if you need to.

const myOnClick = event => console.log('clicked on', event.target);

<Draggable draggableId="draggable-1" index={0}>
  {(provided, snapshot) => {
    const onClick = (() => {
      // dragHandleProps might be null
      if (!provided.dragHandleProps) {
        return myOnClick;
      }

      // creating a new onClick function that calls my onClick
      // event as well as the provided one.
      return event => {
        provided.dragHandleProps.onClick(event);
        // You may want to check if event.defaultPrevented
        // is true and optionally fire your handler
        myOnClick(event);
      };
    })();

    return (
      <div>
        <div
          ref={provided.innerRef}
          {...provided.draggableProps}
          {...provided.dragHandleProps}
          onClick={onClick}
        >
          Drag me!
        </div>
        {provided.placeholder}
      </div>
    );
  }}
</Draggable>;

2. snapshot: (DraggableStateSnapshot)**

type DraggableStateSnapshot = {|
  isDragging: boolean,
|};

The children function is also provided with a small amount of state relating to the current drag state. This can be optionally used to enhance your component. A common use case is changing the appearance of a Draggable while it is being dragged. Note: if you want to change the cursor to something like grab you will need to add the style to the body. (See DragDropContext > style above)

<Draggable draggableId="draggable-1" index={0}>
  {(provided, snapshot) => {
    const style = {
      backgroundColor: snapshot.isDragging ? 'blue' : 'grey',
      ...provided.draggableProps.style,
    };

    return (
      <div>
        <div
          ref={provided.innerRef}
          {...provided.draggableProps}
          {...provided.dragHandleProps}
          style={style}
        >
          Drag me!
        </div>
        {provided.placeholder}
      </div>
    );
  }}
</Draggable>;

Interactive child elements within a Draggable

It is possible for your Draggable to contain interactive elements. By default we block dragging on these elements. By doing this we allow those elements to function in the usual way. Here is the list of interactive elements that block dragging from by default:

  • input
  • button
  • textarea
  • select
  • option
  • optgroup
  • video
  • audio
  • contenteditable (any elements that are contenteditable or are within a contenteditable container)

You can opt out of this behavior by adding the disableInteractiveElementBlocking prop to a Draggable. However, it is questionable as to whether you should be doing so because it will render the interactive element unusable. If you need to conditionally block dragging from interactive elements you can add the disableInteractiveElementBlocking prop to opt out of the default blocking and monkey patch the dragHandleProps (DragHandleProps) event handlers to disable dragging as required.

Flow usage

react-beautiful-dnd is typed using flowtype. This greatly improves internal consistency within the codebase. We also expose a number of public types which will allow you to type your javascript if you would like to. If you are not using flowtype this will not inhibit you from using the library. It is just extra safety for those who want it.

Public flow types

// id's
type Id = string;
type TypeId = Id;
type DroppableId = Id;
type DraggableId = Id;

// hooks
type DropResult = {|
  draggableId: DraggableId,
  type: TypeId,
  source: DraggableLocation,
  // may not have any destination (drag to nowhere)
  destination: ?DraggableLocation
|}

type DraggableLocation = {|
  droppableId: DroppableId,
  // the position of the droppable within a droppable
  index: number
|};

// Droppable
type DroppableProvided = {|
  innerRef: (?HTMLElement) => void,
  placeholder: ?ReactElement,
|}

type DraggableStateSnapshot = {|
  isDraggingOver: boolean,
|}

// Draggable
type DraggableProvided = {|
  innerRef: (?HTMLElement) => void,
  draggableProps: ?DraggableProps,
  dragHandleProps: ?DragHandleProps,
  placeholder: ?ReactElement,
|}

type DraggableStateSnapshot = {|
  isDragging: boolean,
|}

export type DraggableProps = {|
  style: ?DraggableStyle,
  'data-react-beautiful-dnd-draggable': string,
|}
type DraggableStyle = DraggingStyle | NotDraggingStyle
type DraggingStyle = {|
  pointerEvents: 'none',
  position: 'fixed',
  width: number,
  height: number,
  boxSizing: 'border-box',
  pointerEvents: 'none',
  top: number,
  left: number,
  margin: 0,
  transition: 'none',
  transform: ?string,
  zIndex: ZIndex,
|}
type NotDraggingStyle = {|
  transition: ?string,
  transition: null | 'none',
|}
type DragHandleProvided = {|
  onMouseDown: (event: MouseEvent) => void,
  onKeyDown: (event: KeyboardEvent) => void,
  onClick: (event: MouseEvent) => void,
  onTouchStart: (event: TouchEvent) => void,
  onTouchMove: (event: TouchEvent) => void,
  tabIndex: number,
  'aria-grabbed': boolean,
  draggable: boolean,
  onDragStart: () => boolean,
  onDrop: () => boolean
|}

Using the flow types

The types are exported as part of the module so using them is as simple as:

import type { DroppableProvided } from 'react-beautiful-dnd';

Typescript

If you are using TypeScript you can use the community maintained DefinitelyTyped type definitions. Installation instructions.

Sample application

We have created a sample application which exercises the flowtypes. It is a super simple React project based on react-create-app. You can use this as a reference to see how to set things up correctly.

Engineering health

Typed

This codebase is typed with flowtype to promote greater internal consistency and more resilient code.

Tested

This code base employs a number of different testing strategies including unit, performance and integration tests. Testing various aspects of the system helps to promote its quality and stability.

While code coverage is not a guarantee of code health, it is a good indicator. This code base currently sits at ~90% coverage.

Performance

This codebase is designed to be extremely performant - it is part of its DNA. It builds on prior investigations into React performance that you can read about here and here. It is designed to perform the minimum number of renders required for each task.

Highlights

  • using connected-components with memoization to ensure the only components that render are the ones that need to - thanks react-redux, reselect and memoize-one
  • all movements are throttled with a requestAnimationFrame - thanks raf-schd
  • memoization is used all over the place - thanks memoize-one
  • conditionally disabling pointer-events on Draggables while dragging to prevent the browser needing to do redundant work - you can read more about the technique here
  • Non primary animations are done on the GPU

Size

Great care has been taken to keep the library as light as possible. It is currently ~34kb (gzip) in size. There could be a smaller net cost if you where already using one of the underlying dependencies.

Supported browsers

This library supports the standard Atlassian supported browsers for desktop:

Desktop Version
Microsoft Internet Explorer(Windows) Version 11
Microsoft Edge Latest stable version supported
Mozilla Firefox (all platforms) Latest stable version supported
Google Chrome (Windows and Mac) Latest stable version supported
Safari (Mac) Latest stable version on latest OS release supported
Mobile Version
Chrome (Android and iOS) Latest stable version supported
Mobile Safari (iOS) Latest stable version supported
Android (Android) The default browser on Android 4.0.3 (Ice Cream Sandwich)

Translations

The documentation for this library is also available in other languages:

These translations are maintained by the community and are not reviewed or maintained by the maintainers of this library. Please raise issues on the respective translations if you would like to have them updated.

Author

Alex Reardon - @alexandereardon - [email protected]

Other maintainers

Jared Crowe - @jaredjcrowe - [email protected]

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Beautiful, accessible drag and drop for lists with React.js

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