react-file-drop/README.md

Zero dependency React component for Gmail or Facebook -like drag and drop file uploader. Drag files anywhere onto the window (or user defined 'frame' prop)! Very extensible, provides many hooks so you can use it to develop any custom behavior that you des

# react-file-drop

Zero dependency React component for Gmail or Facebook -like drag and drop file uploader. Drag files anywhere onto the window (or user defined 'frame' prop)! Very extensible, provides a hook for every event so you can use it to develop any custom behavior that you want.

### V3 is out! See the [changelog](https://github.com/sarink/react-file-drop/blob/master/CHANGELOG.md)

## Demo

https://sarink.github.io/react-file-drop - A very simple live demo with example code and sample CSS

## Why?

I wanted that behavior that facebook, gmail, etc. have where a part of the page highlights immediately when you start dragging a file anywhere on the window. I couldn't find any React component that already did this, so, I made one!

## Dependencies

None! (well, just `prop-types`, but that should already be removed from your prod bundle anyway)

## Browser support

✅ Chrome <br/>
✅ Firefox <br/>
✅ Safari <br/>
✅ IE 11 <br/>
✅ IE Edge <br/>

## Installation

`npm install --save react-file-drop`

## Usage

`import { FileDrop } from 'react-file-drop'`

## How it works

First, you define the `frame` prop (default is the `document`), whenever the user begins dragging file(s) anywhere over this frame, the `target` will get a `file-drop-dragging-over-frame` class name, and the `onFrameDragEnter` callback will fire.

Next, define an `onDrop` prop, whenever a user drops their files onto the `target`, this callback will be triggered.

Lastly, you'll need to style it.

You can also define an `onTargetClick` prop if you want to let user browse their files from disk. Below you can find instruction how to do that.

## Styling

By default, the component comes with no styles. You can grab the [demo CSS](https://raw.githubusercontent.com/sarink/react-file-drop/master/demo/src/Demo.css) to get started.

For custom class names (if you're using something like JSS) you can use the following props:

- `className`
- `targetClassName`
- `draggingOverFrameClassName`
- `draggingOverTargetClassName`

## Classnames

`.file-drop`: The outer container element

`.file-drop > .file-drop-target`: This is the target the user has to drag their files to.

`.file-drop > .file-drop-target.file-drop-dragging-over-frame`: This class will be added to the `target` whenever the user begins dragging a file over the `frame`, and it will be removed when they leave

`.file-drop > .file-drop-target.file-drop-dragging-over-target`: This class will be added to the `target` whenever the user begins dragging a file over the `target`, and it will be removed when they leave

## Props

`onDrop: function(files, event)`: Callback when the user drops files onto the target

`onDragOver: function(event)`: Callback when the user is dragging over the target. Also adds the `file-drop-dragging-over-target` class to the `file-drop-target`.

`onDragLeave: function(event)`: Callback when the user leaves the target. Removes the `file-drop-dragging-over-target` class from the `file-drop-target`.

`onTargetClick: function(event)`: Callback when the user clicks _anywhere_ on the target.

`dropEffect - string "copy" || "move" || "link" || "none" (default: "copy")`: Learn more about [HTML5 dropEffects](https://developer.mozilla.org/en-US/docs/Web/API/DataTransfer#dropEffect.28.29). Not available in IE :(

`frame: document || HTMLElement (default: document)`: This is the scope or "frame" that the user must drag some file(s) over to kick things off.

`onFrameDragEnter: function(event)`: Callback when the user begins dragging over the `frame`.

`onFrameDragLeave: function(event)`: Callback when the user stops dragging over the `frame`.

`onFrameDrop: function(event)`: Callback when the user drops files _anywhere_ over the `frame`.

`className: string (default: "file-drop")`: Class given to the outer container div.

`targetClassName: string (default: "file-drop-target")`: Class given to the target div.

`draggingOverFrameClassName: string (default: "file-drop-dragging-over-frame")`: Class given to the target div when file is being dragged over frame.

`draggingOverTargetClassName: string (default: "file-drop-dragging-over-target")`: Class given to the target div when file is being dragged over target.

## Uploading files using click handler

In order to let user upload files with click on the `file-drop-target`, you will need to specify an `input[type="file"]` somewhere in your code. You will also need a ref, that will be passed to the input, to call a `click` method on it.

Steps:

1. Define ref for input:

```javascript
const fileInputRef = useRef(null);
```

2. Define input change handler:

```javascript
const onFileInputChange = (event) => {
  const { files } = event.target;
  // do something with your files...
}
```

3. Add input to your code:

```html
<input
  onChange={onFileInputChange}
  ref={fileInputRef}
  type="file"
  className="hidden"
/>
```

4. Define target click handler:

```javascript
const onTargetClick = () => {
  fileInputRef.current.click()
}
```

5. Add target click handler to `FileDrop` component:

```html
<FileDrop
  onTargetClick={onTargetClick}
```

## Contributing

Your PRs are welcome! To run the app locally:

```
nvm use # Probably optional, but it can't hurt

cd file-drop
npm install
npm start

cd demo
npm install
npm start
```

Now both the apps are running in watch mode. If you make a change to the file-drop code, you should see the demo code automatically rebuild and update in your browser.